Merge pull request #64 from DramaticShape/pcvr

Added PC VR mode. Enable SteamVR, launch the game, toggle the VR menu option to "ON". Tested over virtual desktop/Quest 3. Standalone VR is not supported (too potato).

| control | does |
| --- | --- |
| left stick | move — grid-walks the diorama, free-walks 1ST |
| A / B (X / Y on the left hand) | A / B |
| either trigger | START |
| left stick click | step the VOXEL angle ladder (same as the "3" key) |
| right stick up / down | *diorama only* — zoom the model |
| right stick left / right | *1ST only* — snap-turn 45° |
| grip squeeze + raise / lower that hand | *diorama only* — drag the table's height |
| head | *1ST and battles* — look; FreeMove walks where you look |
| left hand | *1ST and battles* — the Pokédex: menus, dialogs and the 2D battle screen on its screen |

.github/workflows/release.yml

@@ -0,0 +1,200 @@
+name: Release
+
+# Packs the mod into an installable .zip and publishes it as a GitHub Release,
+# once per push to main.
+#
+# Archive layout: every mod file at the archive root, manifest.json included.
+# That is one of the two shapes the game accepts on MODS > Import mod .zip
+# (src/mods/LauncherMods.lua locateRoot: manifest at the root, or inside a
+# single top-level folder). Nothing else is added, so the archive stays
+# installable by hand too.
+#
+# Versioning, first rule that applies wins:
+#   1. the "version" input of a manual run,
+#   2. "[release X.Y.Z]" anywhere in the commit message,
+#   3. manifest.json's own version, when it is ahead of every existing tag,
+#      so bumping the manifest is the normal way to cut a release,
+#   4. otherwise the newest vX.Y.Z tag with its patch incremented
+#      (0.2.99 rolls over to 0.3.0).
+# Whichever wins is written into the manifest.json inside the archive, so a
+# shipped mod never reports a different version than the release it came from.
+#
+# Generated by: python3 tools/modkit.py add-release-workflow <mod-id>
+# MOD_ID below is stamped to this mod's id when the file is copied.
+
+on:
+  push:
+    branches: [master]
+    paths-ignore:
+      - '.github/**'
+      - '**.md'
+  workflow_dispatch:
+    inputs:
+      version:
+        description: "Exact version to release (e.g. 0.3.0). Leave blank to auto-resolve."
+        required: false
+        default: ""
+
+permissions:
+  contents: write
+
+concurrency:
+  group: release
+  cancel-in-progress: false
+
+jobs:
+  release:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Determine version
+        id: ver
+        env:
+          DISPATCH_VERSION: ${{ github.event.inputs.version }}
+        run: |
+          set -euo pipefail
+          python3 - <<'PY' >> "$GITHUB_OUTPUT"
+          import json, os, re, subprocess, sys
+
+          SEMVER = re.compile(r"^(\d+)\.(\d+)\.(\d+)$")
+
+          def sh(*args):
+              return subprocess.run(args, capture_output=True, text=True).stdout.strip()
+
+          def parse(text):
+              m = SEMVER.match(text)
+              return tuple(int(p) for p in m.groups()) if m else None
+
+          def die(msg):
+              print(f"::error::{msg}", file=sys.stderr)
+              raise SystemExit(1)
+
+          with open("manifest.json", encoding="utf-8") as fh:
+              manifest_version = str(json.load(fh).get("version", ""))
+
+          released = sorted(
+              v for v in (parse(tag[1:]) for tag in sh("git", "tag", "-l", "v*").splitlines()) if v
+          )
+          latest = released[-1] if released else None
+
+          override = os.environ.get("DISPATCH_VERSION", "").strip()
+          if not override:
+              found = re.search(r"\[release\s+(\d+\.\d+\.\d+)\]", sh("git", "log", "-1", "--pretty=%B"))
+              override = found.group(1) if found else ""
+
+          manifest_ver = parse(manifest_version)
+          if override:
+              version = parse(override) or die(f"invalid version override {override!r} (expected X.Y.Z)")
+              source = "the override"
+          elif manifest_ver and (latest is None or manifest_ver > latest):
+              version = manifest_ver
+              source = "manifest.json"
+          elif latest:
+              major, minor, patch = latest
+              patch += 1
+              if patch > 99:
+                  minor, patch = minor + 1, 0
+              version = (major, minor, patch)
+              source = "a patch bump on v%d.%d.%d" % latest
+          else:
+              die(f"manifest.json version {manifest_version!r} is not X.Y.Z "
+                  "and there is no vX.Y.Z tag to count from")
+
+          text = "%d.%d.%d" % version
+          print(f"Releasing {text}, from {source}.", file=sys.stderr)
+          print(f"version={text}")
+          print(f"tag=v{text}")
+          PY
+
+      - name: Refuse to clobber an existing release
+        env:
+          GH_TOKEN: ${{ github.token }}
+          TAG: ${{ steps.ver.outputs.tag }}
+        run: |
+          set -euo pipefail
+          if git rev-parse -q --verify "refs/tags/$TAG" >/dev/null; then
+            echo "::error::Tag $TAG already exists. Pick a different version."
+            exit 1
+          fi
+          if gh release view "$TAG" >/dev/null 2>&1; then
+            echo "::error::Release $TAG already exists. Pick a different version."
+            exit 1
+          fi
+
+      - name: Build the mod .zip
+        env:
+          VERSION: ${{ steps.ver.outputs.version }}
+          MOD_ID: "DRAMATIC_SHAPE"
+        run: |
+          set -euo pipefail
+          staging="$RUNNER_TEMP/pkg"
+          out="$GITHUB_WORKSPACE/dist"
+          rm -rf "$staging" "$out"
+          mkdir -p "$staging" "$out"
+
+          git archive HEAD | tar -x -C "$staging"
+
+          rm -rf "$staging/.github" "$staging/.gitattributes" \
+                 "$staging/.gitignore" "$staging/.luarc.json"
+
+          python3 - "$staging/manifest.json" "$VERSION" <<'PY'
+          import json, sys
+          path, version = sys.argv[1], sys.argv[2]
+          with open(path, encoding="utf-8") as fh:
+              manifest = json.load(fh)
+          manifest["version"] = version
+          with open(path, "w", encoding="utf-8") as fh:
+              json.dump(manifest, fh, indent=2, ensure_ascii=False)
+              fh.write("\n")
+          PY
+
+          zip_path="$out/${MOD_ID}-${VERSION}.zip"
+          (cd "$staging" && zip -qr "$zip_path" .)
+          unzip -l "$zip_path"
+
+          unzip -p "$zip_path" manifest.json > "$RUNNER_TEMP/packed-manifest.json"
+          python3 - "$RUNNER_TEMP/packed-manifest.json" "$VERSION" <<'PY'
+          import json, sys
+          path, expected = sys.argv[1], sys.argv[2]
+          with open(path, encoding="utf-8") as fh:
+              version = json.load(fh)["version"]
+          if version != expected:
+              raise SystemExit(f"::error::packed manifest says {version}, expected {expected}")
+          print(f"manifest.json is at the archive root and reports {version}")
+          PY
+
+          (cd "$out" && sha256sum "${MOD_ID}"-*.zip > sha256sums.txt)
+          cat "$out/sha256sums.txt"
+
+      - name: Publish GitHub Release
+        env:
+          GH_TOKEN: ${{ github.token }}
+          VERSION: ${{ steps.ver.outputs.version }}
+          TAG: ${{ steps.ver.outputs.tag }}
+          MOD_ID: "DRAMATIC_SHAPE"
+        run: |
+          set -euo pipefail
+
+          prev="$(git tag -l 'v*' --sort=-v:refname | grep -v "^${TAG}$" | head -1 || true)"
+          range="${prev:+${prev}..}$GITHUB_SHA"
+          changes="$(git log --no-merges --pretty='- %s' "$range" | head -50 || true)"
+
+          notes=$'Download the .zip and install it from the game: MODS > Import mod .zip.'
+          if [ -n "$changes" ]; then
+            notes+=$'\n\n## Changes\n\n'"$changes"
+          fi
+          printf 'Release notes:\n%s\n' "$notes"
+
+          gh release create "$TAG" \
+            --target "$GITHUB_SHA" \
+            --title "$VERSION" \
+            --notes "$notes" \
+            "dist/${MOD_ID}-${VERSION}.zip" \
+            "dist/sha256sums.txt"
+
+          echo "Published release $TAG"

README.md

@@ -3,24 +3,7 @@
 A mod for the [Pokémon Gen 1 Recompilation
 Project](https://github.com/bryanthaboi/pokemon-gen1-recomp-project).
 
-The overworld as a 3D diorama. Terrain is extruded into real geometry,
-occlusion comes from a depth buffer rather than a y-sort, characters stand
-as leaning sprite slabs, a shadow map throws real cast shadows across
-whatever they land on, and an optional tilt-shift pass sells the
-miniature-model look.
-
-And battles fought on that world rather than on a white field. When
-something picks a fight the map's NPCs are culled, the engine's own wipe
-plays over the empty map, and the battle draws over the nearest patch of
-clear ground — shot over the shoulder, the player's mon low and left and
-the enemy high and right, with a slow parallax drift behind them and a
-depth-of-field pass that keeps both of them sharp.
-
-Purely presentational. Nothing here reaches collision, movement, triggers
-or scripts — it changes what the world *looks* like and nothing about what
-it *is*. The battle arena is where the **camera** goes, not where anybody
-goes: no cell, facing, flag or warp is written, so the player is standing
-exactly where the fight found them when it ends.
+The overworld as a voxelized 3D diorama. Also supports experimental first-person and VR.
 
 ## Controls
 
@@ -29,12 +12,56 @@ menu.
 
 | control | does |
 | --- | --- |
-| `3`, or the **VOXEL** options row | OFF → 15 → 35 → 50 → 75 → OFF (camera pitch) |
+| `3`, or the **VOXEL** options row | OFF → 15 → 35 → 50 → 75 → 1ST → OFF (camera pitch) |
+| `SELECT` (pad / touch) | the same step as `3` — for the machines with no number row |
 | `5`, or the **V-GRID** options row | OFF / ON — a one-pixel wireframe on every voxel |
 | `6`, or the **T-SHIFT** options row | OFF → 1 → 2 → 3 → OFF (miniature blur) |
 | `7`, or the **V-CURVE** options row | OFF → 1 → 2 → 3 — bend the world over the horizon |
 | `8`, or the **3D-BTL** options row | ON / OFF — fight on the map instead of on a white field |
-| the **DAYTIME** options row | SYNC / DAY / NIGHT / DUSK / DAWN / CYCLE — what time it is outdoors; held at SYNC (and off the menu) while VOXEL is FULL |
+| `9`, or the **WATER** options row | FULL / SKY / OFF — waves and reflections on water. **SKY** gives the surface its pixel-tall wave columns and puts the sky, the sun, the moon and the cast in them; **FULL** adds a screen-space ray march that also reflects the shoreline, the trees and the buildings standing behind it |
+| the **BACK SPRITES** options row | OFF / ON — keep your own Pokémon on the battle menu, seen from behind in its classic slot, instead of standing it on the map; the foe is still out there. Only on the menu while **3D-BTL** is on, because it decides nothing without it |
+| the **AA** options row | OFF / 2X / 4X — smooth the stair-stepped edges of the 3D world by rendering the diorama larger than the window and folding it back down. The ladder is samples per display pixel: 2X is a canvas root-two wider and taller, 4X one exactly twice the size. Every edge in the projected picture softens with the silhouettes — the tileset's own texels are quads in a perspective view and cross the pixel grid at the same arbitrary angles — so the diorama reads smoother rather than sharper. The most expensive row in the mod, so it is OFF by default and **FULL** leaves it alone |
+| the **DAYTIME** options row | SYNC / DAY / NIGHT / DUSK / DAWN / CYCLE — what time it is outdoors, on the diorama *and* on the flat 2D world; held at SYNC (and off the menu) while VOXEL is FULL |
 
-**3D-BTL** is on by default and is independent of **VOXEL**: battles draw
-on the world whether or not the free-roam camera is pitched over.
+## VR
+
+The **VR** options row (OFF / ON, off by default) drives a PCVR headset
+through OpenXR on Windows — SteamVR, Oculus or WMR.
+
+### VR controls
+
+Suggested onto Touch, Index and WMR controllers (rebindable in the
+runtime's own binding UI); pad, keyboard and mouse all keep working
+alongside.
+
+| control | does |
+| --- | --- |
+| left stick | move — grid-walks the diorama, free-walks 1ST |
+| A / B (X / Y on the left hand) | A / B |
+| either trigger | START |
+| left stick click | step the VOXEL angle ladder (same as the "3" key) |
+| right stick up / down | *diorama only* — zoom the model |
+| right stick left / right | *1ST only* — snap-turn 45° |
+| grip squeeze + raise / lower that hand | *diorama only* — drag the table's height |
+| head | *1ST and battles* — look; FreeMove walks where you look |
+| left hand | *1ST and battles* — the Pokédex: menus, dialogs and the 2D battle screen on its screen |
+
+## Licenses
+
+This mod redistributes one third-party binary:
+
+- **`assets/vr/openxr_loader.dll`** — the Khronos OpenXR loader
+  (version 1.0.10.2, x64, unmodified), © The Khronos Group Inc.,
+  licensed under the **Apache License 2.0**. The full license text ships
+  alongside the DLL at
+  [`assets/vr/LICENSE-openxr_loader.txt`](assets/vr/LICENSE-openxr_loader.txt),
+  as the license requires; keep the two files together if you
+  redistribute this mod. Source:
+  [KhronosGroup/OpenXR-SDK](https://github.com/KhronosGroup/OpenXR-SDK).
+
+Everything else in this mod is original to it, except that the voxel
+geometry and shape profiles are derived from the tile and sprite data of
+the original game, as documented by the
+[pret/pokered](https://github.com/pret/pokered) disassembly. No ROM
+data, artwork or audio is included; the mod reads the assets the host
+game already has.

assets/vr/LICENSE-openxr_loader.txt

@@ -0,0 +1,188 @@
+openxr_loader.dll -- the Khronos OpenXR loader (x64, unmodified)
+Version 1.0.10.2, from the "OpenXR.Loader" NuGet package published by
+The Khronos Group. Source: https://github.com/KhronosGroup/OpenXR-SDK
+
+Copyright (c) The Khronos Group Inc.
+
+Licensed under the Apache License, Version 2.0 (the "License"); the full
+text of the License follows, as its terms require a copy to accompany
+redistribution.
+
+-----------------------------------------------------------------------
+
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
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+      direction or management of such entity, whether by contract or
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+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
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+   END OF TERMS AND CONDITIONS

data/battle_arenas.lua

@@ -41,8 +41,15 @@ return {
   -- ------- routes
   -- narrow, deliberately: the route's interior is a 3-cell-wide lane and the
   -- wide shape only fits in the western connection border, which staged every
-  -- fight at the edge of the world instead of on the road
-  ["ROUTE_1"] = { x = 9, y = 16, shape = "narrow" },
+  -- fight at the edge of the world instead of on the road.
+  --
+  -- Of the seventeen spots the route has outside that border, fourteen are
+  -- this one mid-route clearing and the other three bury the near mon behind
+  -- a hedge -- which the clearance test passes, since it measures terrain
+  -- height along the sightline and a hedge in the apron row is not terrain.
+  -- So the choice is where in the clearing, and this is its west end: tree
+  -- line square behind the pair, nothing crossing either of them.
+  ["ROUTE_1"] = { x = 4, y = 14, shape = "narrow" },
   ["ROUTE_2"] = { x = 1, y = 49, shape = "wide" },
   ["ROUTE_3"] = { x = 57, y = 1, shape = "wide" },
   ["ROUTE_4"] = { x = 46, y = 7, shape = "wide" },

lib/AntiAlias.lua

@@ -0,0 +1,244 @@
+-- Voxel world mode: anti-aliasing, by supersampling.
+--
+-- Everything else in this mod is flat art blitted at whole pixels; this one
+-- pass is real geometry seen through a perspective camera, and a polygon
+-- edge that lands at an angle across the pixel grid is the one place in the
+-- game where a hard stair-step is not a stylistic choice. A roof ridge, a
+-- ledge lip, a tree's silhouette against the sky and the leaning card of a
+-- character are all cut by an edge that has no reason to line up with
+-- anything, and at the shallow rungs -- where the diorama reads most like a
+-- photograph of a model -- they crawl as the camera drifts.
+--
+-- SUPERSAMPLING, not MSAA and not a filter over the finished frame, for two
+-- reasons that both come out of what the pass already is:
+--
+--   MSAA would take the water with it. The reflections read the frame's own
+--   DEPTH buffer as a texture (Voxel3D.beginWater), and a multisampled depth
+--   attachment is not a thing a fragment shader in this dialect can sample.
+--   The row would have quietly switched the other row off.
+--
+--   An edge filter (FXAA and its relatives) works from the finished colour
+--   alone, and would be GUESSING where the edges are out of one sample per
+--   pixel -- inventing detail it never rendered, and unable to tell a
+--   geometry edge from the boundary between two texels of a tileset.
+--
+-- Rendering the pass larger and folding it back down has neither problem:
+-- the depth buffer stays an ordinary texture, every pass in the frame keeps
+-- working in the canvas it was handed, and the fold is an average of samples
+-- that were each rendered honestly. It antialiases everything at once --
+-- geometry, the alpha-cut outline of a sprite card, the wireframe, the
+-- water's ray march -- because none of them know it is happening.
+--
+-- Be clear about what "everything" means: the artwork softens too. A tileset
+-- texel out here is not a screen pixel, it is a quad in a perspective view,
+-- and its boundary crosses the pixel grid at the same arbitrary angle a roof
+-- ridge does -- so the fold averages across it exactly as it averages across
+-- the ridge. That is what an honest extra sample says about that pixel, and
+-- it is also the trade the row IS: the diorama comes out smoother, not
+-- sharper. Which is why this is a row and not something that is simply on.
+--
+-- What it costs is pixels, which is the whole of why this is a row and not
+-- something that is simply on: 2X is half again as many in each direction,
+-- 4X is twice, and the scene pass is the most expensive thing in the frame.
+
+-- the mod namespace (see main.lua): V.require loads a sibling module
+local V = ...
+
+local ModSetting = V.require("ModSetting")
+
+local AntiAlias = {}
+
+-- the key under options.modOptions.DRAMATIC_SHAPE, shared by the row in
+-- OPTIONS and the mod manager's own settings page for this mod
+AntiAlias.KEY = "aa"
+AntiAlias.LABEL = "AA"
+
+-- The ladder is SAMPLES PER DISPLAY PIXEL, which is how an AA setting reads
+-- everywhere else, and the canvas scale each rung costs is its square root:
+-- 2 samples is a canvas 1.41x wider and taller, 4 is one exactly twice the
+-- size. OFF is the default -- this is a cost knob, and a mod should not
+-- quietly spend four times the fill rate of the machine it lands on.
+AntiAlias.setting = ModSetting.new(AntiAlias.KEY, AntiAlias.LABEL,
+                                   { 0, 2, 4 }, { "OFF", "2X", "4X" })
+
+-- The scale the pass currently open was actually expanded by (see expand).
+-- 1 while there is no supersampling in force, which is also what every
+-- reader gets on a frame that never opened a pass at all.
+local live = 1
+
+function AntiAlias.samples()
+  return tonumber(AntiAlias.setting:get()) or 0
+end
+
+-- What the row ASKS for. The scale in force is `factor()`, which is this
+-- clamped to what the driver will actually allocate.
+local function wanted()
+  local n = AntiAlias.samples()
+  if n <= 1 then return 1 end
+  return math.sqrt(n)
+end
+
+-- The biggest canvas this driver admits to, or nil where it will not say.
+-- A 4K window at 4X asks for 7680 across, which is past the limit on plenty
+-- of hardware and every phone -- and a refused canvas is not a softer
+-- diorama, it is beginScene returning false and the whole mode falling back
+-- to the flat 2D path.
+local function textureLimit()
+  if not (love.graphics and love.graphics.getSystemLimits) then return nil end
+  local ok, limits = pcall(love.graphics.getSystemLimits)
+  return (ok and limits and limits.texturesize) or nil
+end
+
+-- The size to render `w` x `h` display pixels at, and the size everything
+-- inside the pass then measures itself in.
+--
+-- Also where `live` is set, which is why this must be called once per pass
+-- immediately before beginScene: the wireframe's line width and the FX
+-- overlay's sprite scale are both quoted in DISPLAY pixels and have to be
+-- multiplied up into canvas ones, and the honest multiplier is the one this
+-- returned rather than the one the row asked for.
+function AntiAlias.expand(w, h)
+  local s = wanted()
+  local max = textureLimit()
+  if max and max > 0 then
+    -- clamped rather than abandoned: a window too big for 4X can usually
+    -- still carry some of it, and half a rung of smoothing is worth more
+    -- than a row that silently does nothing at that size
+    s = math.min(s, max / math.max(1, w), max / math.max(1, h))
+  end
+  if not (s > 1.01) then
+    live = 1
+    return w, h
+  end
+  local ew, eh = math.floor(w * s + 0.5), math.floor(h * s + 0.5)
+  live = ew / math.max(1, w)
+  return ew, eh
+end
+
+-- The scale the open pass was expanded by; 1 when it was not.
+function AntiAlias.factor()
+  return live
+end
+
+-- ------- the fold
+--
+-- One target per pass (the free-roam world and the battle's arena are alive
+-- at different moments but reallocating on every battle entry and exit is
+-- what the scene canvas's own slots exist to avoid), reallocated only when
+-- that pass's DISPLAY size changes -- a window resize, or the row itself
+-- moving, which changes the source and not this.
+
+local targets = {}
+
+local function targetFor(slot, w, h)
+  local t = targets[slot]
+  if not (t and t.w == w and t.h == h) then
+    local ok, c = pcall(love.graphics.newCanvas, w, h)
+    if not (ok and c) then return nil end
+    -- nearest, like the canvas it stands in for: this one is composited a
+    -- canvas pixel to a display pixel, and the smoothing has already happened
+    pcall(c.setFilter, c, "nearest", "nearest")
+    if t and t.canvas and t.canvas.release then pcall(t.canvas.release, t.canvas) end
+    t = { canvas = c, w = w, h = h }
+    targets[slot] = t
+  end
+  return t.canvas
+end
+
+-- The box filter, and the whole of why it is a shader rather than a scaled
+-- draw with linear filtering on.
+--
+-- The void this pass renders into is cleared to a TRANSPARENT BLACK, and at
+-- the rungs below FULL a good deal of the frame is still that. Averaging a
+-- straight-alpha edge against it drags the result toward black as well as
+-- toward transparent, and then the engine's own composite multiplies by that
+-- alpha a second time -- so every silhouette against the void would come out
+-- ringed with a dark fringe, which is exactly the artefact the row is here to
+-- remove.
+--
+-- So the taps are premultiplied before they are averaged and divided back out
+-- after, which is the arithmetic that makes an edge pixel mean "half covered
+-- by this colour" instead of "covered by half of this colour".
+--
+-- Four taps, half a source texel from the destination centre. At 4X those
+-- land dead on the four texel centres the destination pixel covers, so it is
+-- an exact 2x2 box; at 2X the source grid does not divide, and the bilinear
+-- fetch under each tap widens the box a little rather than missing samples.
+local SHADER = [[
+  uniform vec2 tap;        // half a SOURCE texel, in uv
+  vec4 effect(vec4 color, Image tex, vec2 tc, vec2 sc) {
+    vec4 a = Texel(tex, tc + vec2(-tap.x, -tap.y));
+    vec4 b = Texel(tex, tc + vec2( tap.x, -tap.y));
+    vec4 c = Texel(tex, tc + vec2(-tap.x,  tap.y));
+    vec4 d = Texel(tex, tc + vec2( tap.x,  tap.y));
+    float al = (a.a + b.a + c.a + d.a) * 0.25;
+    if (al <= 0.0) return vec4(0.0);
+    vec3 sum = a.rgb * a.a + b.rgb * b.a + c.rgb * c.a + d.rgb * d.a;
+    return vec4(sum * 0.25 / al, al) * color;
+  }
+]]
+
+local shader = nil            -- nil = untried, false = unavailable
+
+local function getShader()
+  if shader == nil then
+    local ok, sh = pcall(love.graphics.newShader, SHADER)
+    shader = (ok and sh) or false
+  end
+  return shader or nil
+end
+
+-- Fold `canvas` down to `w` x `h` and hand back the result.
+--
+-- Returns the input untouched when there is nothing to fold -- the row is
+-- off, or the canvas already IS that size -- so a caller can run it
+-- unconditionally, and so can a headless test run. A target that would not
+-- allocate is the same answer: the pass is lost either way if this hands back
+-- something the wrong size, so it hands back the input and the frame draws at
+-- the size it was rendered.
+function AntiAlias.resolve(canvas, w, h, slot)
+  if not canvas then return canvas end
+  local ok, cw, ch = pcall(canvas.getDimensions, canvas)
+  if not ok or (cw == w and ch == h) then return canvas end
+  local target = targetFor(slot or "world", w, h)
+  if not target then return canvas end
+
+  local sh = getShader()
+  local prevBlend, prevAlpha = love.graphics.getBlendMode()
+  -- the scene canvas filters nearest for its usual 1:1 blit; the taps want
+  -- linear, put back below so every other pass finds what it expects
+  pcall(canvas.setFilter, canvas, "linear", "linear")
+  love.graphics.setColor(1, 1, 1, 1)
+  -- replace, not alpha-blend: this is an image-processing copy, and the alpha
+  -- the shader worked out has to land as itself rather than be composited
+  -- against whatever the target held
+  love.graphics.setBlendMode("replace", "premultiplied")
+  if sh then
+    love.graphics.setShader(sh)
+    pcall(sh.send, sh, "tap", { 0.5 / cw, 0.5 / ch })
+  end
+  local drew = pcall(function()
+    love.graphics.setCanvas(target)
+    love.graphics.clear(0, 0, 0, 0)
+    love.graphics.draw(canvas, 0, 0, 0, w / cw, h / ch)
+  end)
+  love.graphics.setCanvas()
+  love.graphics.setShader()
+  love.graphics.setBlendMode(prevBlend or "alpha", prevAlpha)
+  pcall(canvas.setFilter, canvas, "nearest", "nearest")
+  return drew and target or canvas
+end
+
+-- Drop the GPU objects (window resize, hot reload).
+function AntiAlias.invalidate()
+  for slot, t in pairs(targets) do
+    if t.canvas and t.canvas.release then pcall(t.canvas.release, t.canvas) end
+    targets[slot] = nil
+  end
+end
+
+function AntiAlias.row()
+  return AntiAlias.setting:row()
+end
+
+return AntiAlias

lib/BattleCam.lua

@@ -124,6 +124,14 @@ BattleCam.PAN_PERIOD = 26         -- seconds for one there-and-back
 BattleCam.PAN_DOLLY = 0.02        -- how far the eye breathes, as a fraction
 BattleCam.DOLLY_PERIOD = 37
 
+-- Hold the rig perfectly still (VR sets this while a session runs). The
+-- drift exists to give a FLAT screen the depth cue the picture cannot
+-- have; a headset gets real parallax from the player's own head, and a
+-- picture that sways on its own inside VR reads as the world lurching --
+-- on the floating panel especially, where the battle screen is watched
+-- from a fixed seat.
+BattleCam.still = false
+
 BattleCam.t = 0
 
 function BattleCam.reset()
@@ -160,12 +168,14 @@ function BattleCam.rig(arena, groundY)
   local R = BattleCam.rigFor(arena)
   local mx, mz = arena.mid[1], arena.mid[2]
 
-  local yaw = BattleCam.PAN_YAW * phase(BattleCam.t, BattleCam.PAN_PERIOD)
+  local yaw = BattleCam.still and 0
+              or BattleCam.PAN_YAW * phase(BattleCam.t, BattleCam.PAN_PERIOD)
   local c, s = math.cos(yaw), math.sin(yaw)
   -- the breath scales the whole offset, height included, so the eye moves
   -- along its own line to the arena and the pitch of the shot never changes
-  local k = 1 + BattleCam.PAN_DOLLY
-              * phase(BattleCam.t, BattleCam.DOLLY_PERIOD)
+  local k = BattleCam.still and 1
+            or 1 + BattleCam.PAN_DOLLY
+                   * phase(BattleCam.t, BattleCam.DOLLY_PERIOD)
   local dx = (R.side * c - R.back * s) * k
   local dz = (R.side * s + R.back * c) * k
 

lib/BattlePics.lua

@@ -9,12 +9,76 @@
 -- of every eye, the highlight down a Pikachu's cheek: all of it turns into a
 -- hole with the world showing through, and the mon reads as a stencil.
 --
--- So the paper is put back, and only where the paper was: the pic is read
--- back once, the transparent region OUTSIDE the figure is flood-filled from
--- the border, and every transparent pixel the flood could not reach -- every
--- hole enclosed by the artwork -- is filled opaque white. The silhouette is
--- untouched, so the mon still cuts cleanly against the world; only its
--- insides stop being see-through.
+-- So the paper is put back, and only where the paper was. Which pixels those
+-- are is the whole problem, and it has to be ANSWERED rather than looked up:
+-- the hardware drew the mon's white belly and the white field behind it with
+-- the same shade, the decoder keyed both to the same alpha, and nothing in the
+-- image says which was which. There is no distinction to recover; there is one
+-- to draw.
+--
+-- The rule is a flood fill from OUTSIDE the figure: whatever the background
+-- can reach is background, and whatever it cannot is paper. What makes that
+-- work is where the flood is allowed to start.
+--
+-- Start it at the image border and it fills everything and answers nothing.
+-- Gen 1 figures are open drawings and a belly is not a sealed room: it walks
+-- out between two legs and off the bottom of the frame. Run over all 352 of
+-- this game's battle pics, that finds an enclosed hole in NONE of them -- so
+-- it left every mon a stencil, which is the bug this file exists to fix and
+-- for a long time did not.
+--
+-- So the flood is started at the edges of the artwork's own BOUNDING BOX, and
+-- the left, the right and the top are seeded whole. The sky between a pair of
+-- ears reaches the top edge and stays sky; the gap between a body and a raised
+-- tail reaches the side and stays gap.
+--
+-- The BOTTOM is the interesting one, because two completely different things
+-- meet the underside of a figure and they have to be told apart.
+--
+--   A DRAIN is where the drawing simply ran out -- a belly whose white carries
+--   on down until the artist stopped, leaking to the outside through the inch
+--   between a body and a leg. Seal it: what is above it is the mon.
+--
+--   A MOUTH is the space BETWEEN two legs, or under an arch. It is background
+--   that happens to be enclosed on three sides. Leave it open: the world
+--   should show through the gap in a trainer's stride.
+--
+-- What separates them is how WIDE the opening is, and on this game's art that
+-- is not a close call. Measured along the bottom of every battle pic: the
+-- drains run 3 and 4 pixels (Clefairy's back, Wartortle's back, Red's back)
+-- and the mouths run 10, 12, 14 and 17 (a Rattata's underbelly, Blue's stride,
+-- Brock's, a Pikachu's back). Nothing lands between 4 and 10, so the cut is
+-- taken at 6 with room either side rather than tuned to a single sprite.
+--
+-- Apart from that one number the rule is exact: no pixel is filled for what
+-- surrounds it, only because the background provably cannot get to it. And it
+-- needs no idea whether it is holding a front pic, a back one or a trainer --
+-- fronts are near-solid silhouettes with almost nothing inside them to fill,
+-- and they come back untouched because that is what their own shape says, not
+-- because they were special-cased.
+--
+-- The drain/mouth cut is for a pic STANDING ON THE MAP, where a mouth is a
+-- real hole with real ground behind it. A pic PINNED TO THE MENU has no such
+-- hole to be: under BACK SPRITES the player's mon is drawn in the GB's own
+-- slot with its feet flush on the text box (BattleState.backPlacement pins
+-- row 96), so the only thing under its lowest row is white box. Nothing can
+-- reach it from below, whatever the opening's width, and the caller says so
+-- by asking for a SEALED BOTTOM -- for which the rule stops being a heuristic
+-- and becomes exact: paper is whatever the background cannot walk to from the
+-- left, the right or the top.
+--
+-- That is the difference between a Pikachu that reads as a mon and one that
+-- reads as wireframe. The pale-bodied back pics -- Pikachu, Seel, Dewgong,
+-- Chansey, Jigglypuff -- are drawn as OUTLINES: everything inside the ink is
+-- shade 0 and every one of them is keyed away, so the figure is a rim with the
+-- arena showing through it. Each one also has a wide opening along its bottom,
+-- which the drain cut correctly reads as a mouth and the sealed bottom
+-- correctly does not. Twelve of this game's 151 back pics turn on it; the
+-- other 139 come back byte-identical either way, because they had nothing
+-- under them the flood was getting in through.
+--
+-- The silhouette is untouched, so the mon still cuts cleanly against the
+-- world; only its insides stop being see-through.
 --
 -- Read back off the GPU rather than off the asset, deliberately. What comes
 -- back is the pic the engine actually decided to draw -- species palette,
@@ -27,14 +91,23 @@ local V = ...
 
 local BattlePics = {}
 
--- Cached by the image the engine handed over. Weak keys, so a pic that goes
--- out of scope takes its filled twin with it rather than pinning a texture
--- for the session.
-local cache = setmetatable({}, { __mode = "k" })
+-- Cached by the image the engine handed over, one table per bottom rule --
+-- the same pic answers differently sealed and unsealed, and a single table
+-- would hand the wrong twin back to whichever caller asked second. Weak keys,
+-- so a pic that goes out of scope takes its filled twin with it rather than
+-- pinning a texture for the session.
+local function newCache()
+  return {
+    [false] = setmetatable({}, { __mode = "k" }),
+    [true]  = setmetatable({}, { __mode = "k" }),
+  }
+end
+local cache = newCache()
 
--- What an enclosed hole is filled with. White, because white is what the
--- battle field was: this restores the pixel the artist drew and the engine
--- then keyed away, it does not invent a new one.
+-- What an enclosed hole is filled with when the pic itself offers nothing
+-- better. White, because white is what the battle field was: this restores the
+-- pixel the artist drew and the engine then keyed away, it does not invent a
+-- new one.
 BattlePics.FILL = { 1, 1, 1, 1 }
 
 -- Anything at or under this alpha counts as keyed-out rather than drawn.
@@ -44,6 +117,21 @@ local CUT = 0.5
 -- its data back, so it is drawn into a canvas of its own size and the canvas
 -- is read -- which is also what makes this work for every path that produces
 -- a pic, without knowing which one produced this one.
+--
+-- The canvas is forced to dpiscale = 1, and that is the whole difference
+-- between a pic and a MONSTER. love.graphics.newCanvas defaults its dpiscale
+-- to the surface's, conf.lua turns highdpi on for Android and iOS, and
+-- Android's density is routinely 2.75 -- so newCanvas(56, 56) hands back a
+-- 154x154 texture there, the pic is drawn into it magnified to fill it, and
+-- newImageData reads the magnified copy back at its own PIXEL size. The image
+-- built from that is 2.75x the artwork, drawPicsLayer draws it at 1:1 because
+-- it trusts getWidth(), and the mon stands on the map nearly three times the
+-- size of the square it is supposed to cover. Desktop never saw it: dpiscale
+-- is already 1 there. Nor did every species, because only a pic with an
+-- enclosed hole in it comes back through here at all (see `changed` below) --
+-- so a Pidgey came out giant and the mon beside it did not, which is what
+-- makes this read as a sprite bug rather than a scale one. See the engine's
+-- own src/render/PixelCanvas.lua, which exists for exactly this reason.
 local function readBack(img)
   local w, h = img:getDimensions()
   if w <= 0 or h <= 0 then return nil end
@@ -52,7 +140,7 @@ local function readBack(img)
   local prevR, prevG, prevB, prevA = love.graphics.getColor()
   local data = nil
   local ok = pcall(function()
-    local canvas = love.graphics.newCanvas(w, h)
+    local canvas = love.graphics.newCanvas(w, h, { dpiscale = 1 })
     love.graphics.setCanvas(canvas)
     love.graphics.clear(0, 0, 0, 0)
     love.graphics.setBlendMode("replace", "premultiplied")
@@ -72,32 +160,120 @@ local function readBack(img)
   return ok and data or nil
 end
 
--- Mark every transparent pixel reachable from the border. That set is the
--- OUTSIDE; everything transparent it does not reach is an enclosed hole.
+-- The box the artwork actually occupies, or nil for a pic with no ink in it.
+--
+-- Not the image: a pic is centred in a 7x7-tile buffer and a small mon leaves
+-- whole rows and columns of nothing around itself. The bottom of THIS box is
+-- the cut the rule below turns on, and the bottom of the image is just empty
+-- frame some distance under it.
+local function inkBounds(data, w, h)
+  local x0, y0, x1, y1 = w, h, -1, -1
+  for y = 0, h - 1 do
+    for x = 0, w - 1 do
+      local _, _, _, a = data:getPixel(x, y)
+      if a > CUT then
+        if x < x0 then x0 = x end
+        if x > x1 then x1 = x end
+        if y < y0 then y0 = y end
+        if y > y1 then y1 = y end
+      end
+    end
+  end
+  if x1 < x0 then return nil end
+  return x0, y0, x1, y1
+end
+
+-- The colour the keyed-away shade would have had: the LIGHTEST colour still
+-- standing in the pic.
+--
+-- Pure white is only the right answer while the pic is still grays, and by the
+-- time it reaches here it usually is not. picImage hands a pic over AFTER the
+-- bake -- a species SGB colour, a BGP fade mid-animation, PAL_BLACK for the
+-- whole screen while the blackout text is up -- and shade 0 travels with the
+-- rest. A white belly inside a blacked-out mon would be the one lit thing on a
+-- dark screen; inside a warm-palette mon it would be a cold patch the artist
+-- never drew.
+--
+-- So the paper is read off the pic rather than assumed, which needs shade 0 to
+-- have survived somewhere in it. It always has: every one of this game's 151
+-- back pics keeps at least one opaque shade-0 pixel -- a highlight down a
+-- cheek, the white of an eye -- because only the shade-0 pixels the decoder
+-- could reach were keyed. So what comes back is the baked shade 0 itself, not
+-- an approximation of it, and it tracks every palette the engine picks without
+-- being told which one that was.
+--
+-- Ranked by channel sum, which orders four DMG shades exactly: a palette maps
+-- all three channels monotonically, so lightest by sum is lightest full stop.
+local function paperColor(data, x0, y0, x1, y1)
+  local best, pr, pg, pb = -1, nil, nil, nil
+  for y = y0, y1 do
+    for x = x0, x1 do
+      local r, g, b, a = data:getPixel(x, y)
+      if a > CUT then
+        local lum = r + g + b
+        if lum > best then best, pr, pg, pb = lum, r, g, b end
+      end
+    end
+  end
+  if best < 0 then return nil end
+  return pr, pg, pb
+end
+
+-- The widest opening along the bottom of a figure that still counts as a drain
+-- rather than a mouth. See the header for the measurements either side of it.
+BattlePics.DRAIN = 6
+
+-- Mark every transparent pixel the BACKGROUND can reach, flooding inward from
+-- the edges of the artwork's box: the left, the right and the top whole, and
+-- along the bottom only those openings wide enough to be background rather
+-- than the underside of a figure the drawing ran out of -- or none of them at
+-- all, for a pic whose feet are on the text box and which therefore has
+-- nothing behind its lowest row to let in.
+--
+-- Confined to the box as well as seeded from it, so the empty frame under a
+-- short pic cannot walk around a sealed drain and come back up through it.
 --
 -- An explicit stack rather than recursion: a 56x56 pic is three thousand
 -- pixels and a keyed-out background is most of them, which is a deeper call
 -- chain than is worth risking for no gain.
-local function markOutside(data, w, h)
+local function markOutside(data, w, h, x0, y0, x1, y1, sealBottom)
   local outside = {}
   local stack, top = {}, 0
+  local function clear(x, y)
+    local _, _, _, a = data:getPixel(x, y)
+    return a <= CUT
+  end
   local function push(x, y)
-    if x < 0 or y < 0 or x >= w or y >= h then return end
+    if x < x0 or y < y0 or x > x1 or y > y1 then return end
     local key = y * w + x
     if outside[key] then return end
-    local _, _, _, a = data:getPixel(x, y)
-    if a > CUT then return end
+    if not clear(x, y) then return end
     outside[key] = true
     top = top + 1
     stack[top] = key
   end
-  for x = 0, w - 1 do
-    push(x, 0)
-    push(x, h - 1)
+  for x = x0, x1 do push(x, y0) end
+  for y = y0, y1 do
+    push(x0, y)
+    push(x1, y)
   end
-  for y = 0, h - 1 do
-    push(0, y)
-    push(w - 1, y)
+  -- the bottom, run by run: a wide one is the gap between two legs and lets
+  -- the world through, a narrow one is where a belly ran out and is sealed.
+  -- Skipped whole for a pic on the box, where even the widest of them has
+  -- white paper behind it rather than arena.
+  if not sealBottom then
+    local x = x0
+    while x <= x1 do
+      if clear(x, y1) then
+        local from = x
+        while x <= x1 and clear(x, y1) do x = x + 1 end
+        if (x - from) > BattlePics.DRAIN then
+          for k = from, x - 1 do push(k, y1) end
+        end
+      else
+        x = x + 1
+      end
+    end
   end
   while top > 0 do
     local key = stack[top]
@@ -114,9 +290,15 @@ end
 -- The pic with its enclosed holes filled, or the pic itself when that could
 -- not be done (no pixel access, a driver that refused the readback). Never
 -- nil for a non-nil argument: a caller must always have something to draw.
-function BattlePics.filled(img)
+--
+-- sealBottom for a pic pinned to the text box rather than standing on the map:
+-- see the header. A caller that does not say defaults to the map, which is
+-- where all but one of this mod's pics are.
+function BattlePics.filled(img, sealBottom)
   if not img then return img end
-  local hit = cache[img]
+  sealBottom = sealBottom and true or false
+  local slot = cache[sealBottom]
+  local hit = slot[img]
   if hit ~= nil then return hit or img end
 
   local made = nil
@@ -124,16 +306,24 @@ function BattlePics.filled(img)
     local data = readBack(img)
     if not data then return end
     local w, h = data:getDimensions()
-    local outside = markOutside(data, w, h)
+    local x0, y0, x1, y1 = inkBounds(data, w, h)
+    if not x0 then return end          -- a pic with nothing drawn in it
+    local outside = markOutside(data, w, h, x0, y0, x1, y1, sealBottom)
     local fill = BattlePics.FILL
+    local pr, pg, pb = paperColor(data, x0, y0, x1, y1)
+    local fr = pr or fill[1]
+    local fg = pg or fill[2]
+    local fb = pb or fill[3]
     local changed = false
-    for y = 0, h - 1 do
+    -- only inside the box: everything beyond it is frame the artist never
+    -- reached, and filling that would put the mon in a white rectangle
+    for y = y0, y1 do
       local row = y * w
-      for x = 0, w - 1 do
+      for x = x0, x1 do
         if not outside[row + x] then
           local _, _, _, a = data:getPixel(x, y)
           if a <= CUT then
-            data:setPixel(x, y, fill[1], fill[2], fill[3], fill[4])
+            data:setPixel(x, y, fr, fg, fb, fill[4])
             changed = true
           end
         end
@@ -146,12 +336,12 @@ function BattlePics.filled(img)
     made = out
   end)
 
-  cache[img] = (ok and made) or false
+  slot[img] = (ok and made) or false
   return made or img
 end
 
 function BattlePics.invalidate()
-  cache = setmetatable({}, { __mode = "k" })
+  cache = newCache()
 end
 
 return BattlePics

lib/BattleScene.lua

@@ -42,6 +42,7 @@ local BattleCam = V.require("BattleCam")
 local BattleBillboard = V.require("BattleBillboard")
 local VoxelGrid = V.require("VoxelGrid")
 local DayNight = V.require("DayNight")
+local AntiAlias = V.require("AntiAlias")
 local PaletteFX = require("src.render.PaletteFX")
 local Map = require("src.world.Map")
 
@@ -141,9 +142,10 @@ local function prefetchArena(state, host)
   for _, nb in ipairs(state.neighbors or {}) do live[nb.map.id] = true end
   ChunkMesher.setLive(live)
   TerrainAtlas.setLive(live)
-  local terrain = ChunkMesher.request(host, false, nil, true)
-                  or ChunkMesher.peek(host, true)
-  return terrain, {}
+  ChunkMesher.request(host, false, nil, true)
+  local terrain, water = ChunkMesher.pair(host, false)
+  if not terrain then terrain, water = ChunkMesher.pair(host, true) end
+  return terrain, {}, water, {}
 end
 
 -- ------- the sun
@@ -208,6 +210,91 @@ end
 
 BattleScene.monCards = monCards
 
+-- The MOVE-ANIMATION layer's place in the world: a BILLBOARD facing the
+-- eye, for the GB-frame effects texture OverworldBattle.animTexture
+-- renders (the engine's own drawAnimLayer, caught on a canvas).
+--
+-- Effects are 2D drawings like the pics, and the pics' answer holds for
+-- them too: a drawing must FACE the eye that is looking (the mon cards
+-- yaw toward it per eye -- see monMatrix). So the frame stands on the
+-- arena's midpoint, yawed at the eye like the cards are, and the classic
+-- layout's two slot marks are pinned where each CELL lands on that plane
+-- along this very eye's own ray -- so from the eye that is looking, a
+-- burst authored at a slot sits exactly over the mon standing in for it,
+-- and a projectile crossing the frame crosses the arena. The vertical
+-- scale is the mon cards' own (FULL_W / FULL_PIC), so an effect is sized
+-- like the pics it plays over.
+--
+-- An eye standing (nearly) ON the arena's axis sees the two cells in
+-- line and the pinning degenerates; the frame then falls back to the
+-- fixed plane through both cells, which that eye views edge-on anyway.
+--
+-- Reads Voxel3D.eye at CALL time, like the cards -- call it per eye.
+-- Returns the model matrix for BattleBillboard's unit card (x -0.5..0.5,
+-- y 0..1 up, v flipped), or nil where the anchors are degenerate.
+function BattleScene.fxCard(arena, groundY, anchors)
+  local p, e = anchors.player, anchors.enemy
+  local dgb = e[1] - p[1]
+  if math.abs(dgb) < 1 then return nil end
+  local GW, GH = BattleScene.GB_W, BattleScene.GB_H
+  local Px, Py, Pz = arena.player[1], groundY, arena.player[2]
+  local Ex, Ey, Ez = arena.enemy[1], groundY, arena.enemy[2]
+  local s = BattleBillboard.FULL_W / BattleBillboard.FULL_PIC
+  local Mx, My, Mz = (Px + Ex) / 2, groundY, (Pz + Ez) / 2
+
+  local eye = Voxel3D.eye
+  local yaw = BattleBillboard.yawToward(Mx, Mz, eye)
+  local nx, nz = math.sin(yaw), math.cos(yaw)     -- out of the frame, at the eye
+  local rx, rz = math.cos(yaw), -math.sin(yaw)    -- the frame's own right
+
+  -- where a world point sits ON the billboard, as (right, up) coordinates
+  -- about the midpoint: slid along the eye's ray onto the plane, so the
+  -- mark and the mon line up from exactly the seat that is looking
+  local function inPlane(qx_, qy_, qz_)
+    if eye then
+      local dqx, dqy, dqz = qx_ - eye[1], qy_ - eye[2], qz_ - eye[3]
+      local denom = dqx * nx + dqz * nz
+      if math.abs(denom) > 1e-6 then
+        local t = ((Mx - eye[1]) * nx + (Mz - eye[3]) * nz) / denom
+        qx_ = eye[1] + dqx * t
+        qy_ = eye[2] + dqy * t
+        qz_ = eye[3] + dqz * t
+      end
+    end
+    return (qx_ - Mx) * rx + (qz_ - Mz) * rz, qy_ - My
+  end
+  local pax, pay = inPlane(Px, Py, Pz)
+  local eax, eay = inPlane(Ex, Ey, Ez)
+
+  if math.abs(eax - pax) < 4 then
+    -- edge-on: the fixed plane through both cells, world-axis mapping
+    local ux = (Ex - Px) / dgb
+    local uy = (Ey - Py - s * (p[2] - e[2])) / dgb
+    local uz = (Ez - Pz) / dgb
+    local cx = Px + ux * (0.5 * GW - p[1])
+    local cy = Py + uy * (0.5 * GW - p[1]) + s * (p[2] - GH)
+    local cz = Pz + uz * (0.5 * GW - p[1])
+    local nl = math.sqrt(ux * ux + uz * uz)
+    local fx, fz = 0, 1
+    if nl > 1e-9 then fx, fz = uz / nl, -ux / nl end
+    return { ux * GW, 0, fx, cx,
+             uy * GW, s * GH, 0, cy,
+             uz * GW, 0, fz, cz,
+             0, 0, 0, 1 }
+  end
+
+  -- in-plane travel per GB pixel of frame x, solved so both marks land:
+  -- inPlane(gb) = (pax, pay) + U * (gbx - p.x) + (0, s) * (p.y - gby)
+  local ux = (eax - pax) / dgb
+  local uy = (eay - pay - s * (p[2] - e[2])) / dgb
+  local cxp = pax + ux * (0.5 * GW - p[1])
+  local cyp = pay + uy * (0.5 * GW - p[1]) + s * (p[2] - GH)
+  return { rx * ux * GW, 0, nx, Mx + rx * cxp,
+           uy * GW, s * GH, 0, My + cyp,
+           rz * ux * GW, 0, nz, Mz + rz * cxp,
+           0, 0, 0, 1 }
+end
+
 -- The sun has to see the mons too, or they stand on the ground without
 -- putting anything on it. They are the one thing in this scene that MOVES,
 -- so `token` -- a counter the caller bumps whenever a pic could have changed
@@ -227,7 +314,8 @@ local function shadowSignature(state, arena, terrain, nbMesh, token)
 end
 
 local function castShadows(state, arena, terrain, nbMesh, cx, cy, vw, vh,
-                           atlasFor, cards, token, host, neighbors)
+                           atlasFor, cards, token, host, neighbors,
+                           water, nbWater)
   if not ShadowMap.available() then return end
   local sig = shadowSignature(state, arena, terrain, nbMesh, token)
   if not ShadowMap.stale(sig) then return end
@@ -237,6 +325,14 @@ local function castShadows(state, arena, terrain, nbMesh, cx, cy, vw, vh,
   for i, nb in ipairs(neighbors) do
     ShadowMap.draw(nbMesh[i], atlasFor(nb.map), Mat4.translate(nb.ox, 0, nb.oy))
   end
+  -- the water surface is its own reflective pass now (see Water) and so is
+  -- no longer inside the terrain mesh; the sun still has to see it, or the
+  -- light's map has a hole at every lake
+  ShadowMap.draw(water, atlasFor(host), nil)
+  for i, nb in ipairs(neighbors) do
+    ShadowMap.draw(nbWater and nbWater[i], atlasFor(nb.map),
+                   Mat4.translate(nb.ox, 0, nb.oy))
+  end
   -- thin cards are snugged toward the sun (ShadowMap.snug) so their shadows
   -- keep contact with their bases instead of starting a bias-width away
   ShadowMap.draw(ChunkMesher.flowers(host), atlasFor(host),
@@ -249,10 +345,15 @@ local function castShadows(state, arena, terrain, nbMesh, cx, cy, vw, vh,
   -- the mons themselves, as the same cards the camera will see. Their alpha
   -- is the silhouette, so what lands on the ground is the shape of the
   -- Pokemon rather than a blob standing in for one.
+  -- marked as the CAST, so a fight staged at the water's edge does not lay a
+  -- cut-out of a Pokemon across the lake (see ShadowMap.sprites); the arena's
+  -- own floor still takes them, which is the shadow that matters here
+  ShadowMap.sprites(true)
   for _, card in ipairs(cards or {}) do
     ShadowMap.draw(BattleBillboard.mesh(), card.tex,
                    ShadowMap.snug(card.model))
   end
+  ShadowMap.sprites(false)
 
   ShadowMap.finish(sig)
 end
@@ -299,9 +400,36 @@ end
 BattleScene.FLASH_COLOR = { 1, 1, 1 }
 BattleScene.FLASH_STRENGTH = 0.5
 
+-- ------- the tile clock, while the overworld is not the one drawing
+--
+-- Water and flowers animate off TileRenderer's 60Hz counter, and the ENGINE
+-- only advances it from OverworldState:drawWorld -- which runs under dialogs
+-- and menus, but not under a battle, because a battle draws instead of the
+-- overworld rather than over it. So for the length of a staged fight the
+-- counter stood still: the water tiles stopped rotating their pixels and the
+-- wave field, which is driven off the same number so the two cannot drift
+-- (see Water), stopped with them. A lake in the background of a battle was a
+-- photograph.
+--
+-- Ticked HERE rather than from the mod's update hook, because here is the
+-- one place that means "a staged battle is drawing this frame, and the
+-- overworld is not". From the update hook the condition would have to be
+-- guessed at, and a frame where both ran would double the rate.
+local function tickTiles()
+  local Game = require("src.core.Game")
+  local ow = Game and Game.overworld
+  local top = Game and Game.stack and Game.stack:top()
+  -- during the wipe INTO a battle the overworld can still be the one
+  -- drawing, and it is ticking the clock itself; two ticks in a frame would
+  -- run the water at double speed
+  if top and ow and top == ow then return end
+  pcall(require("src.render.TileRenderer").tick)
+end
+
 function BattleScene.render(state, arena, textures, token)
   if not (state and state.map and arena) then return nil end
   if not Voxel3D.available() then return nil end
+  tickTiles()
 
   -- the floor the fight is staged on: normally the player's own, sometimes
   -- another floor of the same cave or building (see BattleArena)
@@ -326,7 +454,7 @@ function BattleScene.render(state, arena, textures, token)
 
   -- shares the free-roam mode's request/evict bookkeeping, so a battle warms
   -- exactly the meshes walking around would have and nothing extra
-  local terrain, nbMesh = prefetchArena(state, host)
+  local terrain, nbMesh, water, nbWater = prefetchArena(state, host)
   if not terrain then return nil end
 
   local lx, ly, s, pw, ph = BattleScene.letterbox()
@@ -356,7 +484,7 @@ function BattleScene.render(state, arena, textures, token)
   local cards = monCards(arena, groundY, textures)
   Voxel3D.camera = nil
   castShadows(state, arena, terrain, nbMesh, cx, cy, vw, vh, atlasFor,
-              cards, token, host, neighbors)
+              cards, token, host, neighbors, water, nbWater)
 
   -- An opaque void either way. Outdoors the camera is low enough that the
   -- horizon is genuinely in frame, so it is sky; indoors it is the dark end
@@ -385,7 +513,16 @@ function BattleScene.render(state, arena, textures, token)
     -- its own canvas slot: this renders at the window's pixel size and the
     -- free-roam pass does too, but the two are alive at different moments
     -- and a shared slot would reallocate on every battle entry and exit
-    if not Voxel3D.beginScene(pw, ph, cx, cy, vw, vh, sky, "battle") then
+    --
+    -- AA, if the row asks for it, renders it larger still and folds it back
+    -- to pw x ph below (see AntiAlias). The framing is untouched by that:
+    -- the lens was widened by the window's RATIO to the letterbox and the
+    -- rig solved in the GB's own frame, so a bigger canvas is more samples
+    -- of the identical shot -- which is why the pins below still measure in
+    -- pw and ph, and why the HUDs and the depth of field, drawn onto the
+    -- folded canvas afterwards, stay the chunky GB art they are.
+    local rw, rh = AntiAlias.expand(pw, ph)
+    if not Voxel3D.beginScene(rw, rh, cx, cy, vw, vh, sky, "battle") then
       return
     end
     Voxel3D.draw(terrain, atlasFor(host), nil)
@@ -393,6 +530,22 @@ function BattleScene.render(state, arena, textures, token)
       Voxel3D.draw(nbMesh[i], atlasFor(nb.map),
                    Mat4.translate(nb.ox, 0, nb.oy))
     end
+    -- and the water over it -- PLAIN, always: the flat animated tiles, never
+    -- the reflective pass, whatever the WATER row says. The reflection is
+    -- tuned for the overworld's ladder of cameras; this shot's is PLACED --
+    -- low, tilted and framed like a picture -- and under it the pass reads
+    -- wrong: Fresnel opens all the way up, the leaned sky lands on bands the
+    -- framing never shows, and a lake-sized arena comes out as murk wearing
+    -- the tile art. The battle is a stage set, and stage water is painted.
+    -- (No mirror also means the mons need no second draw into one -- they
+    -- just composite over the water below, like everything else on the set.)
+    if water then Voxel3D.draw(water, atlasFor(host)) end
+    for i, nb in ipairs(neighbors) do
+      if nbWater and nbWater[i] then
+        Voxel3D.draw(nbWater[i], atlasFor(nb.map),
+                     Mat4.translate(nb.ox, 0, nb.oy))
+      end
+    end
     -- The mons, standing on their tiles. Depth-tested like everything else,
     -- so a ledge or a tree between the camera and a Pokemon really is in
     -- front of it, and the alpha discard cuts the sprite's own outline out of
@@ -442,7 +595,7 @@ function BattleScene.render(state, arena, textures, token)
                    Mat4.translate(nb.ox, 0, nb.oy), fpull,
                    ShadowMap.snug(Mat4.translate(nb.ox, 0, nb.oy)))
     end
-    local canvas = Voxel3D.endScene()
+    local canvas = AntiAlias.resolve(Voxel3D.endScene(), pw, ph, "battle")
     if not canvas then return end
 
     local vp = Voxel3D.vp
@@ -473,6 +626,11 @@ function BattleScene.render(state, arena, textures, token)
       -- the letterbox, so the depth-of-field pass can put its sharp band on
       -- the two marks rather than on a fraction of the window
       lx = lx, ly = ly, scale = s, pw = pw, ph = ph,
+      -- and the hour's light, for anything drawn over this shot that is NOT
+      -- geometry and so never went past the shader that applied it -- the back
+      -- pic pinned to the menu (see OverworldBattle.backPinned). Neutral
+      -- indoors, which is what DayNight.tint answers for a room.
+      tint = Voxel3D.tint,
     }
   end)
   -- the placed camera is ours for exactly this pass; anything else that

lib/Buildings.lua

@@ -68,6 +68,47 @@ local RECESS_MAX = 24
 local SHADE = { top = 0.95, south = 1.0, north = 0.68,
                 side = 0.78, bottom = 0.5 }
 
+-- ------- how far a merged run may reach: the tile lattice
+--
+-- Merging is what keeps a 90k-voxel house down to ~2k quads, and under a
+-- straight projection a run may be as long as it likes -- a straight line
+-- is a straight line however finely it is cut. THE WORLD CURVE IS NOT
+-- STRAIGHT. It drops every vertex by the square of its distance from the
+-- focus (see WorldCurve), so a quad's interior is the CHORD of a parabola
+-- its neighbours draw the arc of: a run of length L hangs k*L^2/4 below
+-- the short quads butted against it, and the join tears open.
+--
+-- Nothing bounded a run's length before, and the runs that ran away were
+-- the ones wearing a CONSTANT texel -- the roof's black eave outline, its
+-- fascia, the shaded underside -- because a flat run has no art to break
+-- it. Those reached 102px across a gym, which at V-CURVE 3 hangs some
+-- three world pixels under the roof surface beside it: the eave tore off
+-- the roof and the drop showed the building's dark interior through the
+-- slot. (Strip runs, the drawing marching along the atlas, break at the
+-- tileset's own boundaries and were never the problem.)
+--
+-- So a run stops at the next 8px lattice line. Buildings are stamped at
+-- tx*8 (see stamp), so the model's lattice IS the map's: every quad in the
+-- scene -- terrain, props, this -- now ends on the same lines, every join
+-- is vertex-for-vertex, and the bend carries them together. What is left
+-- is the sag WITHIN one cell, k*64/4, which is under a twentieth of a
+-- world pixel at any rung.
+--
+-- It costs quads on a dense city map (Cerulean's object stream goes from
+-- 35.7k to 41.6k, and its longest edge from 102px to 8px) and it costs them
+-- whether the curve is on or not, which is the deliberate trade: the mesh
+-- is cached per map and built asynchronously over seconds, so meshing for
+-- the curve's sake only when the curve is on would mean rebuilding every
+-- live map on a keypress.
+local CELL = 8
+
+-- How far a run starting at `a` may go before it crosses the next lattice
+-- line. Floor-mod, so the awning's negative z lands on the same lines the
+-- positive side does.
+local function runCap(a)
+  return CELL - a % CELL
+end
+
 local function keyOf(tx, ty)
   return (ty + 64) * 4096 + (tx + 64)
 end
@@ -170,6 +211,39 @@ local function read(t, data, perRow)
 
   local inside = {}
   for i = 0, W * H - 1 do inside[i] = not outside[i] end
+
+  -- `scrub` names pixel rects where the drawing paints an object standing
+  -- ON the surface (Red's potted plant on the dining tabletop). The object
+  -- keeps its own standee -- the template's `keep` leaves its tiles
+  -- unclaimed -- so the band beneath it is the one surface the drawing
+  -- implies but never paints clear: every rect pixel takes the field
+  -- shade, sourced from the first field texel outside the rects, and the
+  -- model's top comes out as the plain surface the object sat on.
+  if t.scrub then
+    local function inRect(x, y)
+      for _, r in ipairs(t.scrub) do
+        if x >= r[1] and x <= r[3] and y >= r[2] and y <= r[4] then
+          return true
+        end
+      end
+      return false
+    end
+    local donor = nil
+    for i = 0, W * H - 1 do
+      if col[i] == GREY and inside[i]
+         and not inRect(i % W, math.floor(i / W)) then
+        donor = i
+        break
+      end
+    end
+    for i = 0, W * H - 1 do
+      if inRect(i % W, math.floor(i / W)) then
+        col[i] = GREY
+        ax[i], ay[i] = ax[donor], ay[donor]
+        inside[i] = true
+      end
+    end
+  end
   return { W = W, H = H, col = col, ax = ax, ay = ay, inside = inside }
 end
 
@@ -190,7 +264,24 @@ local function measure(sp, t)
     top[x] = r
   end
 
-  local wallH = H - roofRows
+  -- The drawing's own ground line: the row after the last drawn one. A
+  -- building ends on the black threshold row it stands on (ground == H),
+  -- but furniture is drawn standing on open floor -- the lab table's
+  -- legs stop two rows short of its grid -- and extruding against H
+  -- would float it that far above its own plot.
+  local ground = roofRows
+  for sy = H - 1, roofRows, -1 do
+    local drawn = false
+    for sx = 0, W - 1 do
+      if sp.inside[sy * W + sx] then drawn = true break end
+    end
+    if drawn then
+      ground = sy + 1
+      break
+    end
+  end
+
+  local wallH = ground - roofRows
   local ytop = wallH - 1 + t.slab
 
   -- Side faces must not come out as slabs of outline black: where the
@@ -259,6 +350,14 @@ local function measure(sp, t)
     end
   end
 
+  -- The pane rule reads a LIGHT region the drawing seals behind a BLACK
+  -- frame. A drawing built the other way round -- the healing machine's
+  -- dark screens sealed behind their own white bezels -- inverts under
+  -- it: every lit edge sinks and the black panes stand proud, a black
+  -- lattice a voxel off the face. `panes = false` says the drawing does
+  -- not carry the rule's polarity, so the facade stays flush.
+  if t.panes == false then recess = {} end
+
   -- One representative texel per shade, taken from the building's own art:
   -- the roof's fascia and its undersides are geometry the drawing implies
   -- but never paints, and they must still wear its palette (and pick up
@@ -279,20 +378,510 @@ local function measure(sp, t)
   -- sprite taller than its footprint -- the tower's 16-row drawing
   -- stands on the 8 rows of it that are actually on the map, and D = H
   -- would have pushed its body 64px south into the town plaza.
-  return { top = top, ytop = ytop, D = #t.tiles * 8,
+  -- `depth` (in tile rows) names the plot when the grid runs PAST it
+  -- onto ground the drawing merely stands its legs on: the lab table's
+  -- third row is the walkable cell the player faces it from, and the
+  -- full-grid depth would stand the model in their path.
+  -- `depth` names the plot in TILE ROWS, which is the right grain for a
+  -- building. `depthPx` names it in voxels, for an object whose real
+  -- depth is not a whole tile row -- the Bike Shop toolbox is a box
+  -- standing in the middle of its own cell, not a thing that fills a plot.
+  return { top = top, ytop = ytop,
+           D = t.depthPx or ((t.depth or #t.tiles) * 8),
+           ground = ground,
            recess = recess, interior = interior, shadeTexel = shadeTexel }
 end
 
 -- ----------------------------------------------------------------- build --
 
+-- A desk with separately-classified objects on it (a template's `parts`
+-- list): the methodology's region classification at part granularity.
+-- Upright parts anchor their drawn bottom row to the desk's top plane
+-- and wear their own drawn tops as lids; flat parts (a keyboard, a
+-- sheet of paper) lie one voxel proud at drawn row = depth row -- the
+-- same 1:1 the tabletop itself is drawn with, so an object's height ON
+-- the drawing is its position ON the desk. The desk is the lab-table
+-- slab + base; its lid is the one synthesized surface in the model
+-- (the objects cover every drawn pixel of the tabletop), continued
+-- from the sibling tables' pattern in the drawing's own shades.
+-- tools/building_voxels.py `build_desk_set` is the reference twin.
+local function deskSetModel(sp, pr, t)
+  local W, H, D = sp.W, sp.H, pr.D
+  local ground = pr.ground
+  local col, inside = sp.col, sp.inside
+  local vox = {}
+  local function key(x, y, z) return (y * D + z) * W + x end
+  local function put(x, y, z, i) vox[key(x, y, z)] = i end
+
+  -- de-outline walk bounded to the part, so a part's side faces show
+  -- its own material and never the neighbour's (the sprite-wide walk
+  -- the facade path uses would cross the black seam between units)
+  local function interiorAt(sx, sy, lo, hi)
+    local i = sy * W + sx
+    if col[i] ~= BLACK then return sx end
+    local step = sx < math.floor((lo + hi) / 2) and 1 or -1
+    for d = 1, 3 do
+      local nx = sx + step * d
+      if nx >= lo and nx <= hi then
+        local ni = sy * W + nx
+        if inside[ni] and col[ni] ~= BLACK then return nx end
+      end
+    end
+    return sx
+  end
+
+  -- The parts list, shared by every base piece: a desk plane or an
+  -- open tray rim alike, `plane` is simply the height they ride.
+  local ytop = 0
+  local function buildParts(plane)
+    for _, p in ipairs(t.parts) do
+      Budget.tick()
+      local x0, x1 = p.x[1], p.x[2]
+      if p.kind == "flat" then
+        -- drawn row = depth row by default; `z` renames the origin when
+        -- the flat sits below the desk's own drawn top span (the Center
+        -- PC's keyboard). `at` names the sheet's own height when it does
+        -- not lie on the desk plane (the healing machine's keyboard is a
+        -- shelf mounted on the cabinet's side); `thick` gives it a body
+        -- -- layers below the sheet repeating each column's own texel,
+        -- the same continuation rule every synthesized surface follows.
+        local r0 = p.rows[1]
+        local z0 = p.z or r0
+        local atY = p.at or plane
+        local thick = p.thick or 1
+        if atY > ytop then ytop = atY end
+        for sy = r0, p.rows[2] do
+          local z = z0 + (sy - r0)
+          if z >= 0 and z < D then
+            for sx = x0, x1 do
+              if inside[sy * W + sx] then
+                for y = math.max(0, atY - thick + 1), atY do
+                  put(sx, y, z, sy * W + sx)
+                end
+              end
+            end
+          end
+        end
+      elseif p.kind == "box" then
+        -- A BOX part is a drawn rect standing at its own drawn
+        -- elevation -- equipment attached to the machine rather than an
+        -- object on the desk plane. The rows are face-on art: the top
+        -- row's drawn height IS the box's top (ground - 1 - r0,
+        -- measured), and the box runs down to `base` (default the drawn
+        -- extent; 0 continues it to the floor, the legs-continue rule).
+        -- Height beyond the drawn rows fills the way a roof band does:
+        -- rows before `cycle` map 1:1 from the top, rows after it 1:1
+        -- from the bottom -- the healing machine hoses' foot lands ON
+        -- the floor -- and the cycle window repeats between.
+        local r0, r1 = p.rows[1], p.rows[2]
+        local c0 = p.cycle and p.cycle[1] or r1
+        local c1 = p.cycle and p.cycle[2] or r1
+        local pz = p.z or 0
+        local pd = p.depth
+        local top = pr.ground - 1 - r0
+        local bot = p.base or (pr.ground - 1 - r1)
+        local nTop, nBot = c0 - r0, r1 - c1
+        if top > ytop then ytop = top end
+        for y = bot, top do
+          local k, j = top - y, y - bot
+          local sy
+          if k < nTop then
+            sy = r0 + k
+          elseif j < nBot then
+            sy = r1 - j
+          else
+            sy = c0 + (k - nTop) % (c1 - c0 + 1)
+          end
+          for sx = x0, x1 do
+            local i = sy * W + sx
+            if inside[i] then
+              local ix = interiorAt(sx, sy, x0, x1)
+              for z = pz, pz + pd - 1 do
+                if z >= 0 and z < D then
+                  local px = (z == pz or z == pz + pd - 1) and sx or ix
+                  put(sx, y, z, sy * W + px)
+                end
+              end
+            end
+          end
+        end
+      elseif p.kind == "iso" then
+        -- An ISO part is drawn in 2:1 isometric -- a box TURNED 45
+        -- degrees to the map, so one rhombus carries its top, its front
+        -- and its side at once and no band or facade split can reach
+        -- them. Un-projecting it is that projection run backwards: the
+        -- box stands as a real diamond in plan and every voxel wears the
+        -- texel the drawing paints where that voxel projects TO. The
+        -- drawn top lands on the top, the screen on the screen-facing
+        -- side and the flank on the flank, and nothing is segmented by
+        -- hand -- which is the only way to get this right, because the
+        -- three faces meet on a diagonal no rectangle can name.
+        --
+        -- Everything but the depth centre falls out of the drawn rect,
+        -- because the projection fixes it: the half-width is the drawn
+        -- rhombus's x radius, HALF that again its z radius (2:1 is what
+        -- makes it isometric), the near corner's drawn row is the base
+        -- rhombus's front tip, and whatever drawn height is left once
+        -- that rhombus is accounted for is the box's own height. Bill's
+        -- computer: rx 6, rz 3, base centre row 10, and 6 voxels tall --
+        -- which puts its left corner's vertical edge at drawn rows
+        -- 4..10, exactly where the drawing paints one.
+        --
+        -- `plan` is the one thing the drawing CANNOT state: 2:1 is the
+        -- projection, not the object, so reading rz as the plan radius
+        -- too builds a box half as deep as it is wide -- a slab, not the
+        -- cube the drawing depicts. `plan` names the real z radius and
+        -- the drawn row is scaled into it, so a cube is `plan = rx` and
+        -- the drawing still lands on it pixel for pixel.
+        local pr0, pr1 = p.rows[1], p.rows[2]
+        local rx = math.floor((x1 - x0 + 1) / 2)
+        local rz = math.floor(rx / 2)
+        local plan = p.plan or rz
+        local oy = pr1 - rz
+        local h = oy - rz - pr0
+        local ytp = plane + h
+        if ytp > ytop then ytop = ytp end
+        for sx = x0, x1 do
+          -- doubled, so a rect of even width keeps its centre between
+          -- two columns instead of limping one to the left
+          local dx2 = 2 * sx - (x0 + x1)
+          for dz = -plan, plan do
+            local z = p.z + dz
+            local d2 = math.abs(dx2) * plan + 2 * math.abs(dz) * rx
+            if z >= 0 and z < D and d2 <= (2 * rx + 1) * plan then
+              -- the plan row scaled back into the drawn rhombus
+              local dzs = math.floor((2 * dz * rz + plan) / (2 * plan))
+              for y = 0, h do
+                local sy = oy + dzs - y
+                local i = sy * W + sx
+                if sy >= pr0 and sy <= pr1 and inside[i] then
+                  put(sx, plane + y, z, i)
+                end
+              end
+            end
+          end
+        end
+      else
+        local tr0, tr1 = p.top[1], p.top[2]
+        local fr0, fr1 = p.facade[1], p.facade[2]
+        local pd = p.depth
+        -- `rise` lifts a part off the desk's top plane and `z` names its
+        -- back-most depth row (the field a flat part already carries). An
+        -- object STANDING on a desk needs neither: it starts on the plane
+        -- at the plot's back. The healing machine's console needs both --
+        -- it stands in the FRONT map row of a grid whose back row is the
+        -- wall band it leans against, and its screen head is MOUNTED on
+        -- the console's front two voxels above the body's top. Both come
+        -- off the drawing, not off taste.
+        local base = plane + (p.rise or 0)
+        local pz = p.z or 0
+        local ytp = base + (fr1 - fr0)
+        if ytp > ytop then ytop = ytp end
+        -- `inset` sinks an authored pane one voxel: the pane rule
+        -- applied by hand, for a part whose screen IS sealed behind its
+        -- own black frame while the template's `panes = false` (set for
+        -- the polarity-inverted panel elsewhere in the same drawing)
+        -- blocks the global pass. Same mechanism as a recess: the front
+        -- voxel is simply not placed.
+        local ins = p.inset
+        for sx = x0, x1 do
+          -- the lid: the part's drawn top laid across its depth from the
+          -- back, last row continuing forward; the front lid row is the
+          -- facade's own top row -- the drawn front-top edge.  `stretch`
+          -- maps the drawn band over the whole depth instead, the tray's
+          -- rule: for a part authored DEEPER than its drawing (the house
+          -- stool grown past its drawn seat), clamping would print the
+          -- last row as a long smear off the back band's edge.
+          for z = pz, pz + pd - 1 do
+            local front = z == pz + pd - 1
+            local sy
+            if front then
+              sy = fr0
+            elseif p.stretch then
+              sy = math.min(tr0 + math.floor((z - pz) * (tr1 - tr0 + 1)
+                                             / (pd - 1)), tr1)
+            else
+              sy = math.min(tr0 + z - pz, tr1)
+            end
+            while sy <= tr1 and not inside[sy * W + sx] do sy = sy + 1 end
+            local ok = sy <= tr1 or (front and inside[fr0 * W + sx])
+            if ok and z >= 0 and z < D then
+              put(sx, ytp, z, (front and fr0 or sy) * W + sx)
+            end
+          end
+          -- the body: facade rows anchored to the part's own base
+          for sy = fr0 + 1, fr1 do
+            local y = base + (fr1 - sy)
+            local i = sy * W + sx
+            if inside[i] then
+              local ix = interiorAt(sx, sy, x0, x1)
+              for z = pz, pz + pd - 1 do
+                if z >= 0 and z < D then
+                  if z == pz + pd - 1 then
+                    local sunk = ins and sx >= ins.x[1] and sx <= ins.x[2]
+                                 and sy >= ins.rows[1] and sy <= ins.rows[2]
+                    if not sunk and not pr.recess[i] then put(sx, y, z, i) end
+                  elseif z == pz then
+                    put(sx, y, z, i)
+                  else
+                    put(sx, y, z, sy * W + ix)
+                  end
+                end
+              end
+            end
+          end
+        end
+      end
+    end
+  end
+
+  -- A TRAY is an open container -- the drawing looks down INTO it, so its
+  -- top-view band is not a lid but the inside of the box, and the model
+  -- has to be hollow. Bands, all measured 1:1 like any other band table:
+  -- `top` is the opening (drawn row -> depth row), `front` the near wall
+  -- seen face-on (drawn row -> elevation), `x` the box's outer span and
+  -- `inner` the opening's, so the difference between them is the wall.
+  -- Four walls stand to the rim, the floor slab lies `floor` voxels thick
+  -- under the opening, and the cavity between them is left as AIR -- which
+  -- is the whole point, and what an extruded facade can never be. Parts (a
+  -- standing lid) then ride the rim like any object on a desk's plane.
+  if t.tray then
+    local tr = t.tray
+    local top0 = tr.top[1]
+    local fr0, fr1 = tr.front[1], tr.front[2]
+    local bx0, bx1 = tr.x[1], tr.x[2]
+    local ix0, ix1 = tr.inner[1], tr.inner[2]
+    local floor = tr.floor or 0
+    local plane = fr1 - fr0 + 1            -- the rim: the wall's height
+    -- Which drawn row lies at depth z. The far rim is the band's first
+    -- row and the near rim the front wall's own, and the drawn inside
+    -- STRETCHES over whatever depth is between them: a box deeper than
+    -- its drawing has rows to spare is the ordinary case once the plot
+    -- stops being the grid, and the alternative -- running out of rows
+    -- and repeating the last one -- would print the wrench twice.
+    local lo, hi = top0 + 1, tr.top[2] - 1     -- the drawn inside
+    local span = math.max(1, D - 3)            -- interior depth rows - 1
+    local function trayRow(z)
+      if z == 0 then return top0 end
+      if z == D - 1 then return fr0 end
+      return lo + math.floor((z - 1) * (hi - lo) / span)
+    end
+    for sx = bx0, bx1 do
+      Budget.tick()
+      for z = 0, D - 1 do
+        local hollow = sx >= ix0 and sx <= ix1 and z > 0 and z < D - 1
+        for y = 0, (hollow and floor or plane - 1) do
+          if hollow or y == plane - 1 then
+            -- the opening seen from above: the tray's own floor and
+            -- whatever lies in it -- and the rim is the same band where
+            -- the wall meets it
+            local i = trayRow(z) * W + sx
+            if inside[i] then put(sx, y, z, i) end
+          else
+            -- the wall below the rim: the front band folded up it, the
+            -- drawn face on the front and back layers and the de-outlined
+            -- interior between, exactly as a facade extrudes.
+            --
+            -- NO recess pass here, and it must stay that way: a pane sinks
+            -- by DELETING its front voxel so the one behind becomes the
+            -- pane, and a container's wall is one voxel thick -- there is
+            -- nothing behind it, so the front panel simply opened a hole
+            -- straight into the box and you could see the wrench through it.
+            local sy = fr1 - y
+            local i = sy * W + sx
+            if inside[i] then
+              local px = (z == 0 or z == D - 1) and sx
+                         or interiorAt(sx, sy, bx0, bx1)
+              put(sx, y, z, sy * W + px)
+            end
+          end
+        end
+      end
+    end
+    if plane > ytop then ytop = plane end
+    buildParts(plane)
+    return { at = function(x, y, z)
+               if x < 0 or x >= W or y < 0 or z < 0 or z >= D then
+                 return nil
+               end
+               return vox[key(x, y, z)]
+             end,
+             W = W, ytop = ytop, zmin = 0, zmax = D - 1 }
+  end
+
+  -- No base piece at all: the drawing IS its parts (the house stool -- a
+  -- seat and its legs, nothing under them but floor). The plane the parts
+  -- anchor to is the ground itself.
+  if not t.desk then
+    buildParts(0)
+    return { at = function(x, y, z)
+               if x < 0 or x >= W or y < 0 or z < 0 or z >= D then
+                 return nil
+               end
+               return vox[key(x, y, z)]
+             end,
+             W = W, ytop = ytop, zmin = 0, zmax = D - 1 }
+  end
+
+  -- The desk's top plane. Usually the drawing states it: the fascia and
+  -- base rows it paints below the objects ARE the front face, and their
+  -- row count is the height. Bill's desk paints neither inside its grid
+  -- -- its apron is drawn into the WALKABLE cell in front, and that cell
+  -- is left out on purpose so the chair standing there keeps its own
+  -- tiles -- so `plane` names the height directly and the body below the
+  -- lid is synthesized: the band table's own rim treatment, a shaded box
+  -- closed by the outline where it meets the floor, in the drawing's
+  -- shades via shadeTexel.
+  local f0, f1 = t.desk.fascia[1], t.desk.fascia[2]
+  local b0, b1 = t.desk.base[1], t.desk.base[2]
+  local plane = (b1 - b0 + 1) + (f1 - f0 + 1)
+
+  -- The desk's own PLOT, when the grid holds more than the desk. Bill's
+  -- grid runs on into the walkable cell, because the drawing puts the
+  -- desk's apron AND the chair pushed up to it in the same tiles -- so
+  -- the desk box has to stop at its own cell (`depth`) and stand on its
+  -- own ground line rather than the grid's, which the chair's feet set
+  -- eight rows lower. The base band's last row IS that ground line by
+  -- definition, and for every desk drawn inside its own grid it is the
+  -- measured one to the row (lab table, lab computers, Center PC, the
+  -- Bike Shop toolbox), so this changes nothing for them.
+  -- ...and in voxels (`depthPx`) plus a back origin (`z`) when the desk
+  -- is shallower than a tile row and leans against something: the
+  -- healing machine's cabinet is 10 deep -- its drawn top band's 9 rows
+  -- plus the front edge -- standing against the wall band, so its box
+  -- runs z 16..25 of a 32-deep plot.
+  local deskD = t.desk.depthPx or (t.desk.depth and t.desk.depth * 8) or D
+  local dz0 = t.desk.z or 0
+  local dz1 = dz0 + deskD - 1
+  local deskG = b1 + 1
+  -- ...and the desk's COLUMNS (`x`), when the grid is wider than the
+  -- desk: the healing machine's grid carries its flanking hoses and
+  -- keyboard, and the cabinet is only the middle 16 columns.
+  local dx0 = t.desk.x and t.desk.x[1] or 0
+  local dx1 = t.desk.x and t.desk.x[2] or W - 1
+
+  -- The WALL element: the band the machine backs onto, whose tiles this
+  -- grid claims. The drawing shows it only as the stripe background
+  -- around the tower (the same standing as the potted plants' floor),
+  -- so the block cycles the drawing's own stripe unit -- real pixels of
+  -- column `x`, rows `cycle` -- at wall-band height over the back plot,
+  -- exactly what the neighbouring cells' `wall` pins render.
+  if t.wall then
+    local wl = t.wall
+    local c0, c1 = wl.cycle[1], wl.cycle[2]
+    local cn = c1 - c0 + 1
+    local wx = wl.x or 0
+    for y = 0, wl.h - 1 do
+      Budget.tick()
+      local sy = c0 + (wl.h - 1 - y) % cn
+      for sx = 0, W - 1 do
+        for z = 0, wl.depthPx - 1 do
+          put(sx, y, z, sy * W + wx)
+        end
+      end
+    end
+  end
+
+  -- the base band, extruded exactly like every lab table's
+  for sy = b0, b1 do
+    Budget.tick()
+    local y = deskG - 1 - sy
+    for sx = dx0, dx1 do
+      if inside[sy * W + sx] then
+        local ix = interiorAt(sx, sy, dx0, dx1)
+        for z = dz0, dz1 do
+          local px = (z == dz0 or z == dz1) and sx or ix
+          put(sx, y, z, sy * W + px)
+        end
+      end
+    end
+  end
+  for i in pairs(pr.recess) do
+    local sy = math.floor(i / W)
+    local sx = i % W
+    if sy >= b0 and sy <= b1 and sx >= dx0 and sx <= dx1 then
+      vox[key(sx, deskG - 1 - sy, dz1)] = nil
+    end
+  end
+
+  -- the slab: fascia rows wrap every side
+  for sy = f0, f1 do
+    Budget.tick()
+    local y = plane - 1 - (sy - f0)
+    for sx = dx0, dx1 do
+      for z = dz0, dz1 do put(sx, y, z, sy * W + sx) end
+    end
+  end
+
+  if t.desk.top then
+    -- The lid wears the desk's own drawn top band -- the drawing DOES
+    -- paint this tabletop (the healing machine's white top face with
+    -- its lit west and shaded east strips), so nothing is synthesized
+    -- where it is visible: band rows map back-to-front, the first
+    -- fascia row is the drawn front-top edge, same rule as an upright
+    -- part's lid. Where a part's drawing occludes the band (the monitor
+    -- standing on it), the lid continues the nearest strip BESIDE the
+    -- part -- still the drawing's own pixels, the same sibling-pattern
+    -- rule every synthesized lid follows.
+    local tr0, tr1 = t.desk.top[1], t.desk.top[2]
+    for z = dz0, dz1 do
+      Budget.tick()
+      local sy = z == dz1 and f0 or math.min(tr0 + (z - dz0), tr1)
+      for sx = dx0, dx1 do
+        local px = sx
+        for _, p in ipairs(t.parts) do
+          local px0, px1 = p.x[1], p.x[2]
+          local r0, r1
+          if p.kind == "flat" or p.kind == "iso" or p.kind == "box" then
+            r0, r1 = p.rows[1], p.rows[2]
+          else
+            r0, r1 = p.top[1], p.facade[2]
+          end
+          if sx >= px0 and sx <= px1 and sy >= r0 and sy <= r1 then
+            px = (sx - px0 < px1 - sx) and (px0 - 1) or (px1 + 1)
+            px = math.max(dx0, math.min(dx1, px))
+            break
+          end
+        end
+        put(sx, plane - 1, z, sy * W + px)
+      end
+    end
+  else
+    -- the lid continues the sibling tables' top -- black rim, white
+    -- highlight courses along the north and west, grey field
+    local field = t.desk.lid == "white" and WHITE or GREY
+    for sx = dx0, dx1 do
+      for z = dz0, dz1 do
+        local shade = field
+        if sx == dx0 or sx == dx1 or z == dz0 or z == dz1 then
+          shade = BLACK
+        elseif sx == dx0 + 1 or z == dz0 + 1 then
+          shade = WHITE
+        end
+        put(sx, plane - 1, z, pr.shadeTexel[shade])
+      end
+    end
+  end
+
+  if plane > ytop then ytop = plane end
+  buildParts(plane)
+
+  return { at = function(x, y, z)
+             if x < 0 or x >= W or y < 0 or z < 0 or z >= D then return nil end
+             return vox[key(x, y, z)]
+           end,
+           W = W, ytop = ytop, zmin = 0, zmax = D - 1 }
+end
+
 -- The voxel model as a lookup: `at(x, y, z)` is the index of the sprite
 -- pixel that voxel wears, or nil. Build ORDER is expressed as lookup
 -- order -- roof first, so it overwrites the walls it intersects, and walls
 -- are trimmed to its underside so nothing pokes through the surface.
 local function model(sp, pr, t)
+  if t.parts then return deskSetModel(sp, pr, t) end
   local W, H, D = sp.W, sp.H, pr.D
   local slab, roofRows = t.slab, t.roofRows
-  local top, ytop = pr.top, pr.ytop
+  local top, ytop, ground = pr.top, pr.ytop, pr.ground
 
   -- The roof's drawn span. A sprite inset from its box (B03) leaves outer
   -- columns undrawn in the roof band; they carry no roof at all, and the
@@ -367,16 +956,18 @@ local function model(sp, pr, t)
 
     -- the awning: the band juts two voxels past the walls, front and back
     if ledge0 and (z == -2 or z == -1 or z == D or z == D + 1) then
-      local sy = H - 1 - y
+      local sy = ground - 1 - y
       if sy >= ledge0 and sy <= ledge1 and sp.inside[sy * W + x] then
         return sy * W + x
       end
       return nil
     end
 
-    -- the facade, extruded straight back over the footprint
+    -- the facade, extruded straight back over the footprint. Rows map
+    -- against the measured ground line, not the grid's last row: the two
+    -- differ only for furniture standing on open floor (see measure).
     if z < 0 or z >= D then return nil end
-    local sy = H - 1 - y
+    local sy = ground - 1 - y
     local i = sy * W + x
     if y == 0 and not sp.inside[i] and sy > 0 and sp.inside[i - W] then
       -- the drawing's last row is the ground the building stands on, so
@@ -464,7 +1055,8 @@ local function emit(m, sp, atlasW, atlasH)
   local function runX(y, z, dx, dy, dz, x)
     local i0 = ci(x, y, z)
     local strip, n = nil, 1
-    while true do
+    local cap = runCap(x)
+    while n < cap do
       local nx = x + n
       local i = ci(nx, y, z)
       if not i or ci(nx + dx, y + dy, z + dz) then break end
@@ -556,8 +1148,8 @@ local function emit(m, sp, atlasW, atlasH)
         while z <= zmax do
           local i = ci(x, y, z)
           if i and not ci(x + d, y, z) then
-            local n = 1
-            while z + n <= zmax do
+            local n, cap = 1, runCap(z)
+            while n < cap and z + n <= zmax do
               local j = ci(x, y, z + n)
               if j ~= i or ci(x + d, y, z + n) then break end
               n = n + 1
@@ -666,7 +1258,7 @@ function Buildings.build(S, map, data, perRow)
               end
               built = models[key]
             end
-            Buildings.stamp(S, map, built, tx, ty, bw, bh)
+            Buildings.stamp(S, map, built, tx, ty, bw, bh, t)
           end
         end
       end
@@ -676,9 +1268,24 @@ end
 
 -- One placement: claim its tiles (so the detector leaves them alone and
 -- the mesher paints ground under them) and copy the model into place.
-function Buildings.stamp(S, map, quads, tx, ty, bw, bh)
-  local shape = { class = "building", h = 0, art = "building",
-                  flat = false, authored = true }
+--
+-- Two template fields alter what a claim means, for a drawing that
+-- carries a STANDEE on its surface (Red's potted plant on the dining
+-- table). `keep` names tile ids the stamp must NOT claim: their authored
+-- pins stay live, so the standee scan still stands the object exactly as
+-- it always did. `support` is the model's top plane in voxels: the claim
+-- shape carries it as its height, which is what tells that scan the
+-- standee's shelf -- a plain claim stays at h = 0, and Structures treats
+-- a building claim with height as a full model (skip, never a second
+-- box; see its support branches).
+function Buildings.stamp(S, map, quads, tx, ty, bw, bh, t)
+  local shape = { class = "building", h = (t and t.support) or 0,
+                  art = "building", flat = false, authored = true }
+  local keep = nil
+  if t and t.keep then
+    keep = {}
+    for _, id in ipairs(t.keep) do keep[id] = true end
+  end
 
   -- the ground the building stands on: the commonest flat tile around its
   -- feet, so a house on a path keeps its path
@@ -704,9 +1311,18 @@ function Buildings.stamp(S, map, quads, tx, ty, bw, bh)
   for r = 0, bh - 1 do
     for c = 0, bw - 1 do
       local k = keyOf(tx + c, ty + r)
-      S.shapeAt[k] = shape
-      S.skip[k] = true
-      S.ground[k] = best or false
+      if keep and keep[S.tileAt[k]] then
+        -- unclaimed by request: the tile keeps its pin (the plant's
+        -- cutout pool) and the standee scan finds it there. Only the
+        -- ground is set now, so the scan's own claim of these tiles has
+        -- the building's floor to paint when no flat tile touches a
+        -- cluster ringed by its own furniture.
+        S.ground[k] = best or false
+      else
+        S.shapeAt[k] = shape
+        S.skip[k] = true
+        S.ground[k] = best or false
+      end
     end
   end
 

lib/ChunkMesher.lua

@@ -221,8 +221,18 @@ end
 -- Kept free of any GPU call so it can be exercised headless -- the
 -- geometry is the part with the interesting invariants, and a suite that
 -- needed a real GL context to check them would never run in CI.
-local function runGeometry(map, bodyOnly, masks, sink)
+-- `waterSink`, when given, takes the WATER SURFACE quads instead of the
+-- main sink -- the one class in this world that is drawn as its own pass
+-- (see Water: a mirror cannot be drawn until what it reflects exists).
+-- Nothing else moves: the quads are the same quads, emitted by the same
+-- corner and uv arithmetic at the same recessed height, and the shoreline
+-- faces around them still belong to the GROUND that exposes them.
+--
+-- Omitted, water stays in the terrain mesh exactly as it always did, which
+-- is what the headless geometry() below and the sun's own pass both want.
+local function runGeometry(map, bodyOnly, masks, sink, waterSink)
   local push = sink.push
+  local waterPush = waterSink and waterSink.push or nil
   local tileset = map.tileset
   local S = Structures.forMap(map)
   local perRow = tileset.tilesPerRow or 16
@@ -358,12 +368,14 @@ local function runGeometry(map, bodyOnly, masks, sink)
     return aoSide
   end
 
-  local function topQuad(x0, z0, h, tile, shade)
+  -- `to` routes the quad somewhere other than the main sink -- the water
+  -- surface is the only caller that ever does (see runGeometry's header).
+  local function topQuad(x0, z0, h, tile, shade, to)
     local u0, u1, v0, v1 = uvRect(tile, 0, 8)
-    push({ { x0, h, z0 }, { x0 + 8, h, z0 },
-           { x0 + 8, h, z0 + 8 }, { x0, h, z0 + 8 } },
-         { { u0, v0 }, { u1, v0 }, { u1, v1 }, { u0, v1 } },
-         aoShades(x0 / 8, z0 / 8, h, shade))
+    ;(to or push)({ { x0, h, z0 }, { x0 + 8, h, z0 },
+                    { x0 + 8, h, z0 + 8 }, { x0, h, z0 + 8 } },
+                  { { u0, v0 }, { u1, v0 }, { u1, v1 }, { u0, v1 } },
+                  aoShades(x0 / 8, z0 / 8, h, shade))
   end
 
   -- vertical quad for face direction `d` of the tile column at (x0, z0),
@@ -558,8 +570,14 @@ local function runGeometry(map, bodyOnly, masks, sink)
             end
             topTile = S.tileAt[keyOf(tx, row)]
           end
+          -- water's surface, and only water's: the recessed sheet itself,
+          -- never the ground's shoreline bands around it. A cell an object
+          -- stands on took the branch above and paints synthesized GROUND,
+          -- which is right -- a sign at the waterline stands on a plot, not
+          -- on the pond.
           topQuad(x0, z0, h, topTile,
-                  s.art == "upright" and VOLUME_TOP_SHADE or 1)
+                  s.art == "upright" and VOLUME_TOP_SHADE or 1,
+                  (s.class == "water") and waterPush or nil)
         end
 
         -- sides: 8px bands wherever the neighbour is lower. Band k spans
@@ -764,18 +782,34 @@ end
 -- The raw geometry for `map`: (vertex list, triangle index list, quad
 -- count). Synchronous and GPU-free -- the headless suite and the probes
 -- exercise the invariants through this.
-function ChunkMesher.geometry(map, bodyOnly, masks)
+--
+-- `split` lifts the water surface out, as it is lifted out for the
+-- reflective pass, and appends that sink's own three values -- so the suite
+-- can check the same separation the GPU path relies on without a GPU.
+-- Without it the water is in the first list, which is what every existing
+-- caller reads.
+function ChunkMesher.geometry(map, bodyOnly, masks, split)
   local sink = newTableSink()
-  runGeometry(map, bodyOnly, masks, sink)
-  return sink.results()
+  local waterSink = split and newTableSink() or nil
+  runGeometry(map, bodyOnly, masks, sink, waterSink)
+  if not waterSink then return sink.results() end
+  local v, i, n = sink.results()
+  local wv, wi, wn = waterSink.results()
+  return v, i, n, wv, wi, wn
 end
 
 -- Build the mesh for `map` synchronously. Returns nil when there is
 -- nothing to draw or meshes are unavailable (headless).
-function ChunkMesher.build(map, bodyOnly, masks)
+--
+-- `split` asks for the water surface as a SECOND mesh, returned after the
+-- terrain one -- the shape the reflective pass needs (see Water). Without
+-- it the water is inside the terrain mesh, which is the historical
+-- contract and what every other caller still wants.
+function ChunkMesher.build(map, bodyOnly, masks, split)
   local sink = newSink()
-  runGeometry(map, bodyOnly, masks, sink)
-  return sink.finish()
+  local waterSink = split and newSink() or nil
+  runGeometry(map, bodyOnly, masks, sink, waterSink)
+  return sink.finish(), waterSink and waterSink.finish() or nil
 end
 
 local function quadsMesh(quads)
@@ -819,14 +853,24 @@ end
 -- character card (VoxelScene). A figure baked into the terrain mesh could
 -- not lean, and a shared mesh could not carry per-figure placement.
 --
--- A list, not a mesh: `{ mesh, wx, wz, y }` per figure. Maps have one or
--- none, so the loop that draws them is shorter than the terrain's.
+-- A list, not a mesh: `{ mesh, wx, wz, y, w }` per figure. Maps have one
+-- or none, so the loop that draws them is shorter than the terrain's.
+-- `w` is the card's own width in its local space (its quads start at
+-- x = 0), measured here because the first-person pass yaws a card about
+-- its middle -- a card yawed about its left edge swings off its seat.
 local function buildFigureMeshes(map)
   local out = {}
   for _, f in ipairs(Structures.forMap(map).figures or {}) do
     local mesh = quadsMesh(f.quads)
     if mesh then
-      out[#out + 1] = { mesh = mesh, wx = f.wx, wz = f.wz, y = f.y }
+      local w = 0
+      for _, q in ipairs(f.quads) do
+        for c = 1, 4 do
+          local x = q[c] and q[c][1]
+          if x and x > w then w = x end
+        end
+      end
+      out[#out + 1] = { mesh = mesh, wx = f.wx, wz = f.wz, y = f.y, w = w }
     end
   end
   return out
@@ -858,8 +902,17 @@ local function entry(id)
   return c
 end
 
+-- The water surface that came out of a terrain slot's own build. Kept
+-- beside it rather than in a slot of its own because the two are ONE
+-- answer: a full mesh drawn beside a body build's water would draw the
+-- ring's ponds twice and miss the body's own.
+local function waterSlot(slot)
+  return slot .. "Water"
+end
+
 local function releaseEntry(c)
-  for _, slot in ipairs({ "full", "body", "grass", "flowers" }) do
+  for _, slot in ipairs({ "full", "body", "fullWater", "bodyWater",
+                          "grass", "flowers" }) do
     local mesh = c[slot]
     if mesh and mesh.release then pcall(mesh.release, mesh) end
     c[slot] = nil
@@ -924,13 +977,17 @@ local function runJob(job)
     if c.stale then c.stale.aux = nil end
   end
   local sink = newSink()
-  runGeometry(map, job.slot == "body", job.masks, sink)
+  local waterSink = newSink()
+  runGeometry(map, job.slot == "body", job.masks, sink, waterSink)
   local mesh = sink.finish()
+  local water = waterSink.finish()
   if (gen[job.id] or 0) ~= job.gen then
     if mesh and mesh.release then pcall(mesh.release, mesh) end
+    if water and water.release then pcall(water.release, water) end
     return
   end
   swapSlot(c, job.slot, mesh or false)
+  swapSlot(c, waterSlot(job.slot), water or false)
   if c.stale then
     c.stale[job.slot] = nil
     if not (c.stale.full or c.stale.body or c.stale.aux) then
@@ -1032,12 +1089,14 @@ function ChunkMesher.get(map, bodyOnly, masks)
     if c.stale then c.stale.aux = nil end
   end
   if c[slot] == nil or (c.stale and c.stale[slot]) then
-    local ok, mesh = pcall(ChunkMesher.build, map, bodyOnly, masks)
+    local ok, mesh, water = pcall(ChunkMesher.build, map, bodyOnly, masks,
+                                  true)
     if not ok then
       print("[warn] voxel mesh build failed for " .. tostring(map.id)
             .. ": " .. tostring(mesh))
     end
     swapSlot(c, slot, (ok and mesh) or false)
+    swapSlot(c, waterSlot(slot), (ok and water) or false)
     if c.stale then
       c.stale[slot] = nil
       if not (c.stale.full or c.stale.body or c.stale.aux) then
@@ -1058,6 +1117,21 @@ function ChunkMesher.peek(map, bodyOnly)
   return mesh or nil
 end
 
+-- A slot's terrain mesh AND the water surface lifted out of it, as one
+-- answer. Never builds, like peek.
+--
+-- Both or neither, always from the SAME slot: the water was cut out of that
+-- exact geometry, so pairing a full mesh with a body build's water would
+-- draw the border ring's ponds twice and leave the body's as holes. Callers
+-- that fall back from one variant to the other fall back through this, so
+-- there is nowhere for the two to be chosen separately.
+function ChunkMesher.pair(map, bodyOnly)
+  local c = cache[map.id]
+  if not c then return nil, nil end
+  local slot = bodyOnly and "body" or "full"
+  return c[slot] or nil, c[waterSlot(slot)] or nil
+end
+
 function ChunkMesher.grass(map)
   local c = cache[map.id]
   return c and c.grass or nil
@@ -1068,8 +1142,8 @@ function ChunkMesher.flowers(map)
   return c and c.flowers or nil
 end
 
--- Authored figures as `{ mesh, wx, wz, y }` records -- each placed by its
--- own leaning matrix at draw time, so they cannot share one mesh.
+-- Authored figures as `{ mesh, wx, wz, y, w }` records -- each placed by
+-- its own leaning matrix at draw time, so they cannot share one mesh.
 function ChunkMesher.figures(map)
   local c = cache[map.id]
   local list = c and c.figures

lib/DayTint.lua

@@ -0,0 +1,169 @@
+-- The hour's light on the FLAT world.
+--
+-- The clock already reaches everything the 3D pass draws: VoxelScene and
+-- BattleScene multiply the whole scene by DayNight.tint, so walking around a
+-- route at dusk warms the diorama and midnight turns it blue. Switch voxel
+-- mode off and none of that happens -- the tint is a uniform in a shader the
+-- flat tile path never runs -- so the same evening that fell on the diorama
+-- left the 2D world at permanent noon. One clock, two worlds, one of them
+-- ignoring it.
+--
+-- So the flat composite gets the same multiply, painted as one rectangle.
+--
+-- ------- WHERE, which is the only difficult part
+--
+-- Not on the world canvas. In a colorized mode that canvas is grayscale art
+-- and the blit that puts it on screen runs it through the palette shader,
+-- which classifies each pixel into a shade BY ITS RED CHANNEL. Multiply a
+-- night blue over it first and every shade lands in the wrong bucket -- the
+-- world would not darken, it would change colour into whatever the palette
+-- said the wrong bucket was.
+--
+-- So it goes on AFTER that pass, on the composited world. And not after the
+-- whole frame either: the UI blit is next, and the dialog boxes, the menus and
+-- the HUD are paper held up in front of the world rather than part of it --
+-- the same reason the tilt-shift blur is a worldPresent and not a present.
+--
+-- Which leaves one instant: between the world blit and the UI blit, inside
+-- Renderer:endFrame. There is no seam there -- worldPresent, the engine's own
+-- hook for exactly this, only runs when a PIPELINE produced the world, which
+-- in flat mode is the one thing that did not happen. So endFrame is wrapped
+-- and the UI canvas's own draw call is watched for: `blit` passes the canvas
+-- as the first argument, so the first draw of Renderer.canvas IS the boundary,
+-- by identity rather than by counting or guessing.
+--
+-- The shader and scissor that call arrives under belong to the UI blit already
+-- in progress, so both are put aside for the rectangle and handed straight
+-- back -- otherwise the tint would be palette-remapped and clipped to a zone.
+--
+-- ------- WHEN
+--
+-- Outdoors, on the flat path, when the hour is not neutral. Each of those is
+-- load-bearing:
+--
+--   the flat path   a pipeline that rendered the world already applied the
+--                   tint inside its own shader; painting it again would apply
+--                   the hour twice. worldOverride is exactly "a pipeline drew
+--                   this frame".
+--   outdoors        a room has no sky to take its light from, which is the
+--                   same answer DayNight.tint gives on its own and the same
+--                   one applyRig gives the sun.
+--   not neutral     midday is a multiply by white. Skipped rather than drawn,
+--                   so a game with the clock at DAY issues not one extra call.
+
+-- the mod namespace (see main.lua): V.require loads a sibling module
+local V = ...
+
+local DayNight = V.require("DayNight")
+
+local DayTint = {}
+
+-- Below this the tint is close enough to white that the rectangle would not
+-- change a pixel, and the frame is left exactly as it was.
+DayTint.NEUTRAL = 0.999
+
+local function outdoorNow()
+  local ok, Game = pcall(require, "src.core.Game")
+  if not ok then return false end
+  local ow = Game and Game.overworld
+  local map = ow and ow.map
+  if not map then return false end
+  local okMap, Map = pcall(require, "src.world.Map")
+  if not okMap then return false end
+  local outdoor = map.def and Map.isOutdoor(map.def) or false
+  -- a canopy floor takes the hour's colour and nothing else of it, exactly as
+  -- it does in the 3D pass (BattleScene, VoxelScene)
+  return outdoor or DayNight.isCanopy(map)
+end
+
+-- The colour this frame's world should be multiplied by, or nil to leave the
+-- frame alone.
+function DayTint.forFrame(renderer)
+  if not renderer then return nil end
+  if renderer.worldOverride then return nil end   -- a pipeline drew, and tinted
+  if not renderer.worldActive then return nil end -- no world on screen at all
+  if not outdoorNow() then return nil end
+  local tint = DayNight.tint(true)
+  if not tint then return nil end
+  local r, g, b = tint[1] or 1, tint[2] or 1, tint[3] or 1
+  if r > DayTint.NEUTRAL and g > DayTint.NEUTRAL and b > DayTint.NEUTRAL then
+    return nil
+  end
+  return r, g, b
+end
+
+-- One rectangle over the window, multiplied into whatever is under it.
+--
+-- The whole window rather than the world's own rect, which is what the
+-- engine's warp fade does from the same place and for the same reason: the
+-- border fill, the letterbox bars and the world are all "the world" as far as
+-- the hour is concerned, and black multiplied by anything is still black.
+-- Every read of the graphics state is optional, because a headless driver
+-- ships some of these and not others -- the same reason TerrainAtlas reads the
+-- engine's seams guarded. What cannot be read cannot be put back either, and a
+-- missing accessor must cost the tint rather than the frame.
+local function saved(name, ...)
+  local fn = love.graphics[name]
+  if not fn then return nil end
+  local ok, a, b, c, d = pcall(fn, ...)
+  if not ok then return nil end
+  return a, b, c, d
+end
+
+function DayTint.paint(r, g, b)
+  local gfx = love.graphics
+  local shader = saved("getShader")
+  local sx, sy, sw, sh = saved("getScissor")
+  local blend, alpha = saved("getBlendMode")
+  local pr, pg, pb, pa = saved("getColor")
+  local w, h = gfx.getDimensions()
+
+  if gfx.setShader then gfx.setShader() end
+  if gfx.setScissor then gfx.setScissor() end
+  gfx.setBlendMode("multiply", "premultiplied")
+  gfx.setColor(r, g, b, 1)
+  gfx.rectangle("fill", 0, 0, w, h)
+
+  gfx.setBlendMode(blend or "alpha", alpha)
+  gfx.setColor(pr or 1, pg or 1, pb or 1, pa or 1)
+  if gfx.setScissor then
+    if sx then gfx.setScissor(sx, sy, sw, sh) else gfx.setScissor() end
+  end
+  if shader and gfx.setShader then gfx.setShader(shader) end
+end
+
+function DayTint.install()
+  local Renderer = require("src.render.Renderer")
+  if Renderer.dramaticShapeTintHook then return end
+  local inner = Renderer.endFrame
+
+  function Renderer:endFrame(zones, worldZones)
+    local r, g, b = DayTint.forFrame(self)
+    if not r then return inner(self, zones, worldZones) end
+
+    local gfx = love.graphics
+    local draw = gfx.draw
+    local ui = self.canvas
+    local painted = false
+    gfx.draw = function(tex, ...)
+      -- the UI canvas reaching the screen: the world is finished, the paper
+      -- in front of it has not started. Restored FIRST so the rectangle's own
+      -- drawing cannot re-enter this, and so a UI blit that draws one quad per
+      -- SGB zone only triggers it once.
+      if not painted and tex == ui then
+        painted = true
+        gfx.draw = draw
+        DayTint.paint(r, g, b)
+      end
+      return draw(tex, ...)
+    end
+
+    local ok, err = pcall(inner, self, zones, worldZones)
+    gfx.draw = draw
+    if not ok then error(err, 0) end
+  end
+
+  Renderer.dramaticShapeTintHook = true
+end
+
+return DayTint

lib/FirstPerson.lua

@@ -0,0 +1,723 @@
+-- Voxel world mode: the first-person camera -- the 1ST rung.
+--
+-- Every other rung is the same camera at a different pitch: an orbit over
+-- the view centre, described by one number. 1ST is a different rig
+-- entirely: the eye stands in the player's own head, the view direction is
+-- the player's to steer -- mouse, right stick or a touch drag -- and the
+-- rig rides the placed-camera seam (Voxel3D.camera) that the staged battle
+-- already proved out. Everything downstream of that seam -- the shader
+-- uniforms, project(), the sky's vanishing line, the water's lean -- reads
+-- eye and focus the same way it always has.
+--
+-- What this module owns:
+--
+--   the ATTITUDE   yaw and pitch, fed by whichever look input speaks:
+--                  relative mouse motion, the right stick's rate, or a
+--                  touch dragged across open screen. All three drive the
+--                  same two numbers, so they compose instead of fighting.
+--
+--   the BLEND      easing between the orbit and the head. Stepping onto
+--                  the rung dives the camera from wherever the orbit was
+--                  into the player's eyes over half a second; stepping off
+--                  flies it back out. Mid-blend the rig is a straight lerp
+--                  of the two cameras -- eye, focus, fov, up -- through
+--                  the same placed-camera record.
+--
+--   the MOVE INTENT   the analog vector FreeMove walks the player by,
+--                  gathered here because it is made of the same devices:
+--                  the left stick's raw axes, the touch d-pad's true
+--                  deflection, or the held keys, rotated by this camera's
+--                  yaw so "forward" means "where I am looking".
+--
+-- Deliberately NOT here: movement itself (lib/FreeMove.lua, which owns the
+-- collision walk and the grid the game logic still lives on), and the
+-- billboard math that faces cards at this eye (VoxelScene, which owns
+-- every other card matrix too).
+--
+-- Everything the module reaches -- the mouse's relative mode, the wrapped
+-- love handlers, the touch overlay's hit test -- is pcall-guarded the same
+-- way the 3D pass is: headless runs and drivers without a mouse simply
+-- never see the input, and the rung falls back to holding the 75-degree
+-- orbit.
+
+-- the mod namespace (see main.lua): V.require loads a sibling module
+local V = ...
+
+local Mat4 = V.require("Mat4")
+local Voxel = V.require("VoxelState")
+local Voxel3D = V.require("Voxel3D")
+local WorldCurve = V.require("WorldCurve")
+
+local FirstPerson = {}
+
+-- ------- the rig's numbers
+--
+-- EYE_HEIGHT stands the eye near the top of the 16px sprite -- the head,
+-- not the hat tip -- above the same ground-plus-lift the character card
+-- stands on, so surfing bobs and ledge hops carry the view with them.
+--
+-- FOV is wider than the diorama's ~53 degrees: inside the world, the
+-- diorama's lens reads as a keyhole. 65 vertical is the modern-shooter
+-- middle ground.
+--
+-- FOCUS_DIST is short on purpose: the placed-camera branch derives its
+-- near plane from |eye - focus| (dist * 0.05), and the eye walks within
+-- 2-3 world pixels of a wall face when sliding along it -- a far focus
+-- would push the near plane through the wall and clip a hole in it.
+FirstPerson.EYE_HEIGHT = 13
+FirstPerson.FOV = math.rad(65)
+FirstPerson.FOCUS_DIST = 24
+
+-- Pitch limits, in radians below horizontal (positive looks DOWN). The
+-- world has no ceiling and the sky's bands sit low, so looking far up
+-- shows the void above the gradient; the up-range is clamped tighter than
+-- the down-range for that reason, not a technical one.
+FirstPerson.PITCH_DOWN = math.rad(70)
+FirstPerson.PITCH_UP = -math.rad(50)
+FirstPerson.PITCH_DEFAULT = math.rad(10)
+
+-- how long the dive into (and out of) the head takes, in seconds
+FirstPerson.BLEND_TIME = 0.45
+
+-- ------- look input tuning
+--
+-- MOUSE_SENS is radians per relative-mode count -- about 0.18 degrees per
+-- count, the conventional shooter default. STICK rates are radians per
+-- second at full deflection, with a squared response curve so small
+-- deflections aim and full ones turn. TOUCH_TURN is what one full screen
+-- width of drag turns, mobile-shooter convention.
+FirstPerson.MOUSE_SENS = 0.0032
+FirstPerson.STICK_YAW = 3.5
+FirstPerson.STICK_PITCH = 2.4
+FirstPerson.STICK_DEAD = 0.18
+FirstPerson.TOUCH_TURN = 2.2 * math.pi
+FirstPerson.MOVE_DEAD = 0.25
+
+-- ------- state
+--
+-- Yaw is a world bearing: 0 faces south (+Z, the way a resting sprite
+-- faces), pi/2 east -- the same convention VoxelScene.YAW uses, so a
+-- facing converts to a yaw by table lookup.
+FirstPerson.yaw = 0
+FirstPerson.pitch = FirstPerson.PITCH_DEFAULT
+FirstPerson.blend = 0
+
+local wasEngaged = false
+local stick = { x = 0, y = 0 }        -- right stick, latest event values
+local mouseDX, mouseDY = 0, 0         -- relative counts since last update
+local lookTouch = nil                 -- { id, x, y } of the claimed finger
+local touchMove = nil                 -- the touch d-pad's analog deflection
+local captured = false                -- mouse relative mode engaged by us
+
+-- the placed-camera record this module last handed to Voxel3D, so passes
+-- that key behaviour off "is the first-person rig the one drawing" (the
+-- billboard yaw, the frame remap) can ask by identity rather than by mode
+-- -- the battle's own placed camera must never read as first person
+local rig = nil
+
+local FACING_ANGLE = {
+  down = 0,
+  right = math.pi / 2,
+  up = math.pi,
+  left = -math.pi / 2,
+}
+local FACING_ORDER = { "down", "right", "up", "left" }
+
+local function wrapPi(a)
+  return (a + math.pi) % (2 * math.pi) - math.pi
+end
+
+local function ease(t)
+  return t * t * (3 - 2 * t)
+end
+
+-- ------- gates
+
+-- Whether the 1ST rung is selected and the 3D pass can carry it.
+function FirstPerson.engaged()
+  return Voxel.isFirstPerson(Voxel.level) and Voxel3D.available()
+end
+
+-- Whether first person should be READING the player's inputs right now:
+-- engaged, with the overworld on top of the stack (a menu, a dialog or a
+-- battle above it owns the buttons, exactly as it does for grid walking).
+function FirstPerson.driving()
+  if not FirstPerson.engaged() then return false end
+  local ok, top, ow = pcall(function()
+    local Game = require("src.core.Game")
+    return Game.stack and Game.stack:top(), Game.overworld
+  end)
+  return ok and top ~= nil and top == ow
+end
+
+-- The eased blend, 0 at the orbit and 1 in the head.
+function FirstPerson.blendEased()
+  return ease(FirstPerson.blend)
+end
+
+-- The blend, but only while the free-roam pass's own rig is the placed
+-- camera. The battle scene places a camera of its own through the same
+-- seam, and its cards must keep their stage lean rather than yawing at a
+-- first-person eye that is not looking at them.
+function FirstPerson.cardBlend()
+  if not rig or Voxel3D.camera ~= rig then return 0 end
+  return ease(FirstPerson.blend)
+end
+
+-- A VR eye stepping into the rig's shoes: the VR pass builds its own
+-- placed cameras (one per eye) and hands each one here as it draws, so
+-- everything keyed to "the first-person rig is drawing" -- the billboard
+-- yaw, the frame remap, the hidden player card -- answers for that eye.
+-- In the diorama (blend 0) adoption is inert: cardBlend still reports
+-- zero and the cards keep their lean.
+function FirstPerson.adoptVReye(record)
+  rig = record
+end
+
+-- Whether the player's own card should be left out of the camera draw:
+-- deep enough into the blend that the card would fill the lens from
+-- inside. The sun pass keeps drawing it either way -- a first-person
+-- player still throws a shadow on the ground ahead.
+function FirstPerson.hidePlayer()
+  return FirstPerson.cardBlend() > 0.9
+end
+
+-- ------- attitude
+
+-- Apply a look delta, in radians. Everything that turns the head funnels
+-- through here, so the clamps live once.
+function FirstPerson.lookBy(dyaw, dpitch)
+  FirstPerson.yaw = wrapPi(FirstPerson.yaw + dyaw)
+  FirstPerson.pitch = math.max(FirstPerson.PITCH_UP,
+                       math.min(FirstPerson.PITCH_DOWN,
+                                FirstPerson.pitch + dpitch))
+end
+
+-- The view direction's flat compass facing, for everything that still
+-- thinks in the grid's four directions: the cell A interacts with, the
+-- sprite the sun sees, the direction a blocked slide bonks in.
+function FirstPerson.compassFacing()
+  local s, c = math.sin(FirstPerson.yaw), math.cos(FirstPerson.yaw)
+  if math.abs(s) > math.abs(c) then
+    return s > 0 and "right" or "left"
+  end
+  return c > 0 and "down" or "up"
+end
+
+-- The unit look direction, and its flat (ground-plane) part.
+local function lookDir()
+  local cp = math.cos(FirstPerson.pitch)
+  return math.sin(FirstPerson.yaw) * cp,
+         -math.sin(FirstPerson.pitch),
+         math.cos(FirstPerson.yaw) * cp
+end
+
+function FirstPerson.lookFlat()
+  return math.sin(FirstPerson.yaw), math.cos(FirstPerson.yaw)
+end
+
+-- ------- billboards seen from inside the world
+--
+-- The diorama's cards face south and lean back by the camera's pitch --
+-- correct for a camera that always stands south. An eye that can stand
+-- ANYWHERE sees a south-facing card edge-on from the east, so in first
+-- person every card yaws about its feet to face the eye (cylindrical
+-- billboarding: upright, never tipping). VoxelScene blends its matrices
+-- between the two by cardBlend.
+
+-- The yaw that turns a card's south-facing normal toward the eye.
+function FirstPerson.cardYaw(wx, wz)
+  local eye = rig and rig.eye
+  if not eye then return 0 end
+  local dx, dz = eye[1] - wx, eye[3] - wz
+  if dx * dx + dz * dz < 1e-9 then return 0 end
+  return math.atan2(dx, dz)
+end
+
+-- Which of the four sprite frames an entity shows THIS eye: its facing
+-- rotated into the viewer's own frame, quantised. The flat game's frames
+-- are "how this pose looks from the south", so the apparent facing is the
+-- pose rotated by where the viewer actually stands -- walk behind an NPC
+-- and you see their back, circle to their flank and you see the profile,
+-- exactly as the four frames Gen 1 drew intend.
+function FirstPerson.apparentFacing(facing, wx, wz)
+  local eye = rig and rig.eye
+  local phi = FACING_ANGLE[facing]
+  if not (eye and phi) then return facing end
+  local dx, dz = eye[1] - wx, eye[3] - wz
+  if dx * dx + dz * dz < 1e-9 then return facing end
+  local rel = wrapPi(phi - math.atan2(dx, dz))
+  local idx = math.floor((rel + math.pi / 4) / (math.pi / 2)) % 4
+  return FACING_ORDER[idx + 1]
+end
+
+-- ------- the move intent
+--
+-- The analog vector FreeMove walks by, in CAMERA space: mx strafes (+
+-- right), mz advances (+ forward). Whichever device is actually deflected
+-- answers -- the left stick's raw axes first (the engine quantises them to
+-- a d-pad; the raw pair is the analog truth), then a touch d-pad finger,
+-- then the held keys. Magnitude caps at 1.
+function FirstPerson.moveVector()
+  local ok, Game = pcall(require, "src.core.Game")
+  local input = ok and Game.input or nil
+
+  local ax = input and input.stickAxis or nil
+  if ax then
+    local mag = math.sqrt(ax.x * ax.x + ax.y * ax.y)
+    if mag > FirstPerson.MOVE_DEAD then
+      local t = math.min(1, (mag - FirstPerson.MOVE_DEAD)
+                            / (1 - FirstPerson.MOVE_DEAD))
+      return ax.x / mag * t, -ax.y / mag * t
+    end
+  end
+
+  if touchMove then
+    local mag = math.sqrt(touchMove.x * touchMove.x
+                          + touchMove.y * touchMove.y)
+    if mag > FirstPerson.MOVE_DEAD then
+      local t = math.min(1, mag)
+      return touchMove.x / mag * t, -touchMove.y / mag * t
+    end
+  end
+
+  if input then
+    local mx = (input:isDown("right") and 1 or 0)
+               - (input:isDown("left") and 1 or 0)
+    local mz = (input:isDown("up") and 1 or 0)
+               - (input:isDown("down") and 1 or 0)
+    if mx ~= 0 or mz ~= 0 then
+      local mag = math.sqrt(mx * mx + mz * mz)
+      return mx / mag, mz / mag
+    end
+  end
+  return 0, 0
+end
+
+-- Rotate a camera-space move into world space: forward is the flat look
+-- direction, strafe-right is its right hand. (cross(forward, up) with
+-- forward = (sin y, 0, cos y) and up = +Y lands right on (-cos y, 0,
+-- sin y): face south and your right hand points west.)
+function FirstPerson.moveWorld(mx, mz)
+  local s, c = math.sin(FirstPerson.yaw), math.cos(FirstPerson.yaw)
+  return -c * mx + s * mz, s * mx + c * mz
+end
+
+-- ------- the tick
+
+-- Runs from the pipeline's update hook, every frame whatever the level --
+-- the same tick VoxelState eases the orbit on. Owns the blend, the mouse
+-- capture lifecycle, and the frame's stick-rate look.
+function FirstPerson.update(dt)
+  local engagedNow = FirstPerson.engaged()
+
+  -- entering the rung: the head starts looking the way the sprite faces,
+  -- pitched gently down -- the reading pose of the flat game
+  if engagedNow and not wasEngaged then
+    local ok, facing = pcall(function()
+      local Game = require("src.core.Game")
+      return Game.overworld and Game.overworld.player
+             and Game.overworld.player.facing
+    end)
+    FirstPerson.yaw = (ok and FACING_ANGLE[facing]) or 0
+    FirstPerson.pitch = FirstPerson.PITCH_DEFAULT
+  end
+  wasEngaged = engagedNow
+
+  -- the blend, held at flat until there is terrain to dive into -- the
+  -- same wait Voxel.update keeps for the orbit tween, for the same reason
+  local target = engagedNow and 1 or 0
+  if target > FirstPerson.blend and FirstPerson.blend == 0
+     and not Voxel.ready then
+    target = 0
+  end
+  local step = dt / FirstPerson.BLEND_TIME
+  if FirstPerson.blend < target then
+    FirstPerson.blend = math.min(target, FirstPerson.blend + step)
+  elseif FirstPerson.blend > target then
+    FirstPerson.blend = math.max(target, FirstPerson.blend - step)
+  end
+  if FirstPerson.blend <= 0 and rig then
+    -- fully out: let go of the placed camera (unless a battle already
+    -- swapped its own in, which is not ours to clear)
+    if Voxel3D.camera == rig then Voxel3D.camera = nil end
+    rig = nil
+  end
+
+  -- mouse capture follows engagement: captured whenever the rung is on and
+  -- the window has focus, released the moment either ends. Checked against
+  -- the live mode rather than toggled on edges, so a capture lost to the
+  -- OS (alt-tab) re-arms itself on the next focused frame.
+  local wantCapture = engagedNow
+  if wantCapture and love.window and love.window.hasFocus then
+    local okF, focus = pcall(love.window.hasFocus)
+    wantCapture = okF and focus or false
+  end
+  if love.mouse and love.mouse.setRelativeMode then
+    local okM, isRel = pcall(love.mouse.getRelativeMode)
+    if okM and isRel ~= wantCapture then
+      pcall(love.mouse.setRelativeMode, wantCapture)
+    end
+    captured = wantCapture
+  end
+
+  local driving = FirstPerson.driving()
+
+  -- The mouse's counts, accumulated by the wrapped handler since the last
+  -- tick; dropped unread while something else owns the screen.
+  --
+  -- The yaw sign is NEGATED, here and in every look input below: yaw grows
+  -- south -> east -> north (the world runs +X east, +Z south, and the
+  -- direction is (sin yaw, cos yaw)), which seen from behind the eye is a
+  -- LEFT turn -- so "move the mouse right, look right" means subtracting.
+  local dx, dy = mouseDX, mouseDY
+  mouseDX, mouseDY = 0, 0
+  if driving and (dx ~= 0 or dy ~= 0) then
+    FirstPerson.lookBy(-dx * FirstPerson.MOUSE_SENS,
+                       dy * FirstPerson.MOUSE_SENS)
+  end
+
+  -- the right stick is a rate: radians per second, squared response so
+  -- the first half of the throw aims and the rest turns
+  if driving then
+    local rx, ry = stick.x, stick.y
+    local function curve(v)
+      local a = math.abs(v)
+      if a < FirstPerson.STICK_DEAD then return 0 end
+      a = (a - FirstPerson.STICK_DEAD) / (1 - FirstPerson.STICK_DEAD)
+      return (v < 0 and -1 or 1) * a * a
+    end
+    local cy, cp = curve(rx), curve(ry)
+    if cy ~= 0 or cp ~= 0 then
+      -- negated yaw for the same reason as the mouse above
+      FirstPerson.lookBy(-cy * FirstPerson.STICK_YAW * dt,
+                         cp * FirstPerson.STICK_PITCH * dt)
+    end
+  end
+end
+
+-- ------- the rig itself
+
+-- The orbit camera's eye/focus/fov/up for the frame's centre -- the same
+-- arithmetic Voxel3D.viewProjection runs, restated here because the blend
+-- needs both ends as DATA. Kept textually tiny so the two cannot drift:
+-- focus on the centre, eye FOCAL*vh away at the pitch, up perpendicular
+-- in the YZ plane.
+local function orbitRig(cx, cy, vh)
+  local a = Voxel.angle
+  local dist = Voxel.FOCAL * vh
+  return { cx, dist * math.cos(a), cy + dist * math.sin(a) },
+         { cx, 0, cy },
+         2 * math.atan(1 / (2 * Voxel.FOCAL)),
+         { 0, math.sin(a), -math.cos(a) }
+end
+
+local lastEye = nil                   -- frozen head pose for player-less frames
+
+-- Build this frame's placed camera and hand it to Voxel3D, plus the scene
+-- centre the curve and the depth reference should use. `me` is the
+-- player's posed entry (px, py, gh, lift) or nil (a Fly animation), and
+-- (cx, cy) the orbit's own view centre.
+--
+-- Returns nil with the blend fully out, which is the caller's signal to
+-- leave the orbit in charge.
+function FirstPerson.frame(me, cx, cy, vw, vh)
+  local b = FirstPerson.blend
+  if b <= 0 then
+    if rig and Voxel3D.camera == rig then Voxel3D.camera = nil end
+    rig = nil
+    return nil
+  end
+  local e = ease(b)
+
+  local head
+  if me then
+    head = { me.px + 8,
+             (me.gh or 0) + (me.lift or 0) + FirstPerson.EYE_HEIGHT,
+             me.py + 8 }
+    lastEye = head
+  else
+    head = lastEye or { cx, FirstPerson.EYE_HEIGHT, cy }
+  end
+  local lx, ly, lz = lookDir()
+  local fpFocus = { head[1] + lx * FirstPerson.FOCUS_DIST,
+                    head[2] + ly * FirstPerson.FOCUS_DIST,
+                    head[3] + lz * FirstPerson.FOCUS_DIST }
+
+  local oEye, oFocus, oFov, oUp = orbitRig(cx, cy, vh)
+  local function mix(p, q)
+    return { p[1] + (q[1] - p[1]) * e,
+             p[2] + (q[2] - p[2]) * e,
+             p[3] + (q[3] - p[3]) * e }
+  end
+  local up = mix(oUp, { 0, 1, 0 })
+  local ul = math.sqrt(up[1] * up[1] + up[2] * up[2] + up[3] * up[3])
+  if ul > 1e-6 then up[1], up[2], up[3] = up[1] / ul, up[2] / ul, up[3] / ul
+  else up = { 0, 1, 0 } end
+
+  -- the world curve eases out with the blend: standing inside the world,
+  -- the bend that sells the diorama reads as the ground falling away. A
+  -- true zero (curve declined) needs the field present -- nil would let
+  -- Voxel3D fall back to the setting
+  local k = WorldCurve.k(vh) * (1 - e)
+
+  rig = {
+    eye = mix(oEye, head),
+    focus = mix(oFocus, fpFocus),
+    fov = oFov + (FirstPerson.FOV - oFov) * e,
+    up = up,
+    curve = k,
+  }
+  Voxel3D.camera = rig
+
+  -- the scene centre walks from the orbit's view centre to the head, so
+  -- the curve's focus, the depth reference and the glint's travel follow
+  -- the camera that is actually in charge
+  local sx = cx + (head[1] - cx) * e
+  local sy = cy + (head[3] - cy) * e
+  return rig, sx, sy
+end
+
+-- Where the shadow pass should centre its box: pushed along the flat look
+-- so the fitted frustum -- built for an orbit that always looks north --
+-- covers the ground THIS camera sees. The push is strongest looking
+-- south (the direction the orbit's box barely reaches) and scales with
+-- the blend.
+function FirstPerson.shadowCenter(sx, sy, vh)
+  local e = FirstPerson.cardBlend()
+  if e <= 0 then return sx, sy end
+  local fx, fz = FirstPerson.lookFlat()
+  local ShadowMap = V.require("ShadowMap")
+  local cap = (ShadowMap.FAR_CAP or 2.5) * vh
+  return sx + fx * 0.6 * vh * e,
+         sy + fz * (fz > 0 and (cap - vh * 0.5) or vh * 0.4) * e
+end
+
+-- The first-person facts a shadow signature has to include: the sun's
+-- box is fitted around this camera, so turning the head or walking the
+-- blend has to re-fit it even standing still.
+function FirstPerson.signature()
+  local b = FirstPerson.blend
+  if b <= 0 then return "" end
+  return table.concat({
+    math.floor(b * 64),
+    math.floor(FirstPerson.yaw * 64),
+    math.floor(FirstPerson.pitch * 64),
+  }, ",")
+end
+
+-- ------- input capture
+--
+-- The seams: relative mouse motion has no Game handler at all (the
+-- engine's love.mousemoved only feeds the mouse-as-touch debug path), the
+-- right stick's axes are explicitly ignored by Input, and a touch
+-- anywhere off the overlay's controls dies in TouchControls. Each wrap
+-- forwards everything it does not claim, and claims only while first
+-- person is actually driving -- so with the rung off, every byte flows
+-- exactly where it always did.
+
+local installed = false
+
+function FirstPerson.install()
+  if installed then return end
+  installed = true
+
+  local Game = require("src.core.Game")
+
+  -- ------- right stick
+  do
+    local inner = Game.gamepadaxis
+    function Game:gamepadaxis(joystick, axis, value)
+      if axis == "rightx" then stick.x = value
+      elseif axis == "righty" then stick.y = value end
+      return inner(self, joystick, axis, value)
+    end
+  end
+  -- generic (non-gamepad) sticks: axes 1/2 are the left stick by SDL
+  -- convention and Input already claims them; 3/4 are the usual right
+  -- pair on the same class of device. Real gamepads are excluded -- they
+  -- already spoke through the mapped rightx/righty above, and their RAW
+  -- axis 3 is as likely a trigger as a stick.
+  --
+  -- Two more exclusions, both learned the hard way on Android, where this
+  -- wrap runs BEFORE the engine's own generic-joystick guards:
+  --
+  --   the accelerometer arrives as a joystick named for what it is, with
+  --   gravity pinning an axis well past any deadzone -- the same device
+  --   Game:joystickaxis refuses for movement (#459), refused here by the
+  --   same name test, or the view spins on its own the moment 1ST opens.
+  --
+  --   and a raw axis is only BELIEVED after it has been seen near centre
+  --   once. A stick at rest sits at zero, so a real one earns trust with
+  --   its first touch; a gravity-pinned sensor axis or a trigger resting
+  --   at an extreme never centres and so never steers the look.
+  local function isAccelerometer(joystick)
+    local ok, name = pcall(function() return joystick:getName() end)
+    return ok and type(name) == "string"
+           and name:lower():find("accelerometer", 1, true) ~= nil
+  end
+  local rawCentred = {}
+  do
+    local inner = Game.joystickaxis
+    function Game:joystickaxis(joystick, axis, value)
+      local mapped = joystick and joystick.isGamepad and joystick:isGamepad()
+      if not mapped and (axis == 3 or axis == 4)
+         and not isAccelerometer(joystick) then
+        if math.abs(value) < 0.3 then rawCentred[axis] = true end
+        if rawCentred[axis] then
+          if axis == 3 then stick.x = value else stick.y = value end
+        end
+      end
+      return inner(self, joystick, axis, value)
+    end
+  end
+
+  -- ------- mouse
+  --
+  -- love.mousemoved rather than a Game method, because the engine has no
+  -- Game:mousemoved to wrap -- the callback in the project's main.lua is
+  -- the one place relative counts arrive. Claimed only while captured;
+  -- pass-through otherwise, including the mouse-as-touch path.
+  do
+    local inner = love.mousemoved
+    love.mousemoved = function(x, y, dx, dy, istouch)
+      if captured and not istouch then
+        mouseDX = mouseDX + (dx or 0)
+        mouseDY = mouseDY + (dy or 0)
+        return
+      end
+      if inner then return inner(x, y, dx, dy, istouch) end
+    end
+  end
+  -- While the mouse is captured there is no cursor to click UI with, so
+  -- the buttons become GB buttons: left is A, right is B -- through the
+  -- overlay's own press path, which a rebind can never detach. What WE
+  -- pressed is remembered per button, so the release always reaches the
+  -- overlay even if the capture ended while the button was down --
+  -- otherwise a click that outlives the rung strands A held forever.
+  local mouseHeld = {}
+  local MOUSE_BTN = { [1] = "a", [2] = "b" }
+  do
+    local inner = love.mousepressed
+    love.mousepressed = function(x, y, button, istouch, presses)
+      if captured and not istouch and MOUSE_BTN[button] then
+        local Input = require("src.core.Input")
+        mouseHeld[button] = true
+        Input:overlayPressed(MOUSE_BTN[button])
+        return
+      end
+      if inner then return inner(x, y, button, istouch, presses) end
+    end
+  end
+  do
+    local inner = love.mousereleased
+    love.mousereleased = function(x, y, button, istouch, presses)
+      if mouseHeld[button] then
+        local Input = require("src.core.Input")
+        mouseHeld[button] = nil
+        Input:overlayReleased(MOUSE_BTN[button])
+        return
+      end
+      if inner then return inner(x, y, button, istouch, presses) end
+    end
+  end
+
+  -- ------- touch
+  --
+  -- A finger on open screen -- not on the overlay's d-pad or buttons --
+  -- becomes the look drag. One finger owns the look at a time; every
+  -- other touch flows to TouchControls untouched, so a thumb can drag the
+  -- view while the other walks the d-pad. That d-pad finger is also read
+  -- back ANALOG here: TouchControls quantises it to four directions for
+  -- the grid game, but the deflection it quantised is exactly the move
+  -- vector a free walk wants.
+  local TouchControls = require("src.core.TouchControls")
+
+  local function dpadVector(x, y)
+    local ok, v = pcall(function()
+      local L = TouchControls:layout()
+      local dz = L.dpad
+      local half = dz.w * 0.65
+      return { x = math.max(-1, math.min(1, (x - dz.cx) / half)),
+               y = math.max(-1, math.min(1, (y - dz.cy) / half)) }
+    end)
+    return ok and v or nil
+  end
+
+  do
+    local inner = Game.touchpressed
+    function Game:touchpressed(id, x, y)
+      if FirstPerson.driving() then
+        local onControl = nil
+        pcall(function() onControl = TouchControls:hitTest(x, y) end)
+        if not onControl and not lookTouch then
+          lookTouch = { id = id, x = x, y = y }
+          return
+        end
+        inner(self, id, x, y)
+        if onControl == "dpad" and TouchControls.dpadTouch == id then
+          touchMove = dpadVector(x, y)
+        end
+        return
+      end
+      return inner(self, id, x, y)
+    end
+  end
+  do
+    local inner = Game.touchmoved
+    function Game:touchmoved(id, x, y)
+      if lookTouch and lookTouch.id == id then
+        local w = 1280
+        pcall(function() w = love.graphics.getWidth() end)
+        local per = FirstPerson.TOUCH_TURN / math.max(320, w)
+        if FirstPerson.driving() then
+          -- negated yaw for the same reason as the mouse (see update):
+          -- drag right, look right, the mobile-shooter convention
+          FirstPerson.lookBy(-(x - lookTouch.x) * per,
+                             (y - lookTouch.y) * per)
+        end
+        lookTouch.x, lookTouch.y = x, y
+        return
+      end
+      if touchMove and TouchControls.dpadTouch == id then
+        touchMove = dpadVector(x, y) or touchMove
+      end
+      return inner(self, id, x, y)
+    end
+  end
+  do
+    local inner = Game.touchreleased
+    function Game:touchreleased(id, x, y)
+      if lookTouch and lookTouch.id == id then
+        lookTouch = nil
+        return
+      end
+      if TouchControls.dpadTouch == id then touchMove = nil end
+      return inner(self, id, x, y)
+    end
+  end
+
+  -- a reset that drops held input state drops ours with it
+  do
+    local inner = Game.focus
+    function Game:focus(f)
+      lookTouch, touchMove = nil, nil
+      stick.x, stick.y = 0, 0
+      mouseDX, mouseDY = 0, 0
+      return inner(self, f)
+    end
+  end
+  -- a disconnected controller cannot send the centering event for whatever
+  -- its stick last held -- the engine drops all input state here, and the
+  -- look rate (plus the raw axes' earned trust) goes with it
+  do
+    local inner = Game.joystickremoved
+    function Game:joystickremoved(joystick)
+      stick.x, stick.y = 0, 0
+      rawCentred[3], rawCentred[4] = nil, nil
+      return inner(self, joystick)
+    end
+  end
+end
+
+return FirstPerson

lib/FreeMove.lua

@@ -0,0 +1,345 @@
+-- Voxel world mode: free movement for the first-person rung.
+--
+-- The engine walks a grid: sixteen frames per cell, four directions,
+-- input locked mid-step. Inside a first-person camera that gait reads as
+-- riding a rail, so while 1ST drives, this module replaces the WALK and
+-- nothing else: the player's position becomes continuous, steered by the
+-- camera's own yaw -- push forward and you go where you look, at any
+-- angle, sliding along whatever you graze.
+--
+-- THE GRID IS STILL THE GAME. Every fact the world cares about is a fact
+-- about cells -- what blocks, what warps, what rustles, what bites -- and
+-- this module keeps the player's logical cell synced to wherever the free
+-- walk stands, then reuses the engine's own machinery for every one of
+-- those questions:
+--
+--   passability      the same isWalkableCell / water-while-surfing /
+--                    tile-pair / entity-occupancy verdicts Collision
+--                    hands the grid walker, asked per cell the player's
+--                    body overlaps.
+--
+--   cell arrival     OverworldState:onStepComplete, the same landing
+--                    pipeline a grid step runs -- warps, spinners, gates,
+--                    forced currents, poison, repel, encounters, the
+--                    step counters -- fired once per cell crossed, which
+--                    is exactly the rate a grid walk fires it.
+--
+--   the special pushes   walking off the map edge, into a ledge, or into
+--                    a boulder hands the quantised direction straight to
+--                    checkEdgeExit / checkLedgeHop / checkBoulderPush,
+--                    the engine's own handlers, which validate and stage
+--                    everything themselves (connections, the hop arc,
+--                    the two-push arm). While any of those animates a
+--                    scripted grid move, this module stands aside and
+--                    adopts the result.
+--
+-- Nothing here writes save state, rolls encounters, or decides what a
+-- warp does -- it moves a point, keeps the cell honest, and lets the
+-- engine be the engine. Stepping off the rung snaps the point to its
+-- cell and hands the walk back to the grid, and with the rung off this
+-- module costs one gate check per frame.
+
+-- the mod namespace (see main.lua): V.require loads a sibling module
+local V = ...
+
+local FirstPerson = V.require("FirstPerson")
+
+local FreeMove = {}
+
+-- The body: a circle in the ground plane. Small enough to walk every
+-- one-cell corridor the grid game has (half a cell is 8), big enough to
+-- keep the eye's near plane out of wall faces when sliding along them.
+FreeMove.RADIUS = 5.5
+
+-- World pixels per fixed 60Hz frame -- the grid walker's own speeds (16
+-- frames per 16px cell on foot, 8 on the bike), so distance covered per
+-- second is unchanged and the encounter rate per tile crossed stays the
+-- game's own.
+FreeMove.WALK = 1.0
+FreeMove.BIKE = 2.0
+
+local EPS = 0.01
+
+-- the free position (player centre, world px) and the px/py we last wrote
+-- -- if they differ from the player's, something else (a warp, a script)
+-- moved them, and the free walk adopts rather than fights
+local pos = nil
+local lastPx, lastPy = nil, nil
+
+local function adopt(p)
+  pos = { x = p.px + 8, z = p.py + 8 }
+  lastPx, lastPy = p.px, p.py
+end
+
+function FreeMove.drop()
+  pos = nil
+end
+
+-- named for the suite: the module's live position, nil while dropped
+function FreeMove._pos()
+  return pos
+end
+
+-- ------- the per-cell verdict
+--
+-- The same questions Collision.canMove asks for a grid step, asked of one
+-- cell from the player's current standing. The player's OWN cell never
+-- blocks -- the body must always be free to leave wherever it stands
+-- (a warp mat, the water it is surfing, a cell an NPC just stepped
+-- against).
+
+local function pairBlocked(map, surfing, sx, sy, tx, ty)
+  local Game = require("src.core.Game")
+  local tp = Game.data and Game.data.field and Game.data.field.tilePairs
+  if not tp then return false end
+  local list = surfing and tp.water or tp.land
+  if not list or #list == 0 then return false end
+  local tileset = map.def.tileset
+  local a = map:cellTile(sx, sy)
+  local b = map:cellTile(tx, ty)
+  for _, p in ipairs(list) do
+    if p.tileset == tileset
+       and ((p.a == a and p.b == b) or (p.a == b and p.b == a)) then
+      return true
+    end
+  end
+  return false
+end
+
+-- Why (cx, cy) refuses the player's body, or nil when it may enter:
+-- "bounds" | "tile" | "entity", the grid verdict's own names.
+local function blockedCell(state, p, cx, cy)
+  if cx == p.cellX and cy == p.cellY then return nil end
+  local map = state.map
+  if not map:inBounds(cx, cy) then return "bounds" end
+  if not map:isWalkableCell(cx, cy) then
+    if not (p.surfing and map:isWaterCell(cx, cy)) then return "tile" end
+  end
+  if pairBlocked(map, p.surfing, p.cellX, p.cellY, cx, cy) then
+    return "tile"
+  end
+  local Collision = require("src.world.Collision")
+  if Collision.occupied(state.entities, cx, cy, p) then return "entity" end
+  return nil
+end
+
+FreeMove._blockedCell = blockedCell   -- named for the suite
+
+-- ------- the slide
+--
+-- One axis at a time, clamped at the first refusing cell's face: the
+-- classic axis-separated walk, which is where wall-sliding comes from --
+-- the blocked axis stops and the free one keeps going. Returns the
+-- refusal ("bounds"/"tile"/"entity") when this axis was clamped.
+
+local function slideX(state, p, dx)
+  if dx == 0 then return nil end
+  local r = FreeMove.RADIUS
+  local nx = pos.x + dx
+  local z0 = math.floor((pos.z - r + EPS) / 16)
+  local z1 = math.floor((pos.z + r - EPS) / 16)
+  local hit = nil
+  local edge = dx > 0 and math.floor((nx + r) / 16)
+               or math.floor((nx - r) / 16)
+  for zc = z0, z1 do
+    hit = blockedCell(state, p, edge, zc)
+    if hit then break end
+  end
+  if hit then
+    if dx > 0 then nx = math.min(nx, edge * 16 - r - EPS)
+    else nx = math.max(nx, (edge + 1) * 16 + r + EPS) end
+  end
+  pos.x = nx
+  return hit
+end
+
+local function slideZ(state, p, dz)
+  if dz == 0 then return nil end
+  local r = FreeMove.RADIUS
+  local nz = pos.z + dz
+  local x0 = math.floor((pos.x - r + EPS) / 16)
+  local x1 = math.floor((pos.x + r - EPS) / 16)
+  local hit = nil
+  local edge = dz > 0 and math.floor((nz + r) / 16)
+               or math.floor((nz - r) / 16)
+  for xc = x0, x1 do
+    hit = blockedCell(state, p, xc, edge)
+    if hit then break end
+  end
+  if hit then
+    if dz > 0 then nz = math.min(nz, edge * 16 - r - EPS)
+    else nz = math.max(nz, (edge + 1) * 16 + r + EPS) end
+  end
+  pos.z = nz
+  return hit
+end
+
+-- ------- the blocked push
+--
+-- The grid game's blocked step is where half its verbs live: the map-edge
+-- crossing, the ledge hop, the boulder shove, the route-gate warp fired
+-- by collision, and the honest bonk. Hand the engine the quantised
+-- direction and let its own handlers decide -- each one validates itself
+-- (checkLedgeHop matches the tile pair, checkEdgeExit checks the bounds),
+-- so calling them on every firm push is safe. Returns true when one of
+-- them took the frame over.
+local function pushSpecials(state, dir, why)
+  local p = state.player
+  p.facing = dir      -- the handlers read the push off the facing
+  if why == "bounds" and state:checkEdgeExit(dir) then return true end
+  if state:checkLedgeHop(dir) then return true end
+  if state:checkBoulderPush(dir) then return true end
+  if why ~= "entity" and state:canCollisionWarp() then
+    local Game = require("src.core.Game")
+    local Warp = require("src.world.Warp")
+    local w = Warp.onCollision(state.map, Game.data.field.warpCarpets,
+                               p.cellX, p.cellY, dir)
+    if w then
+      state:takeWarp(w.def)
+      return true
+    end
+  end
+  if why ~= "entity" then
+    if (state.bumpCooldown or 0) <= 0 then
+      local Game = require("src.core.Game")
+      require("src.core.Sound").play(Game.data, "Collision")
+      state.bumpCooldown = 16
+    end
+  end
+  return false
+end
+
+-- ------- the tick
+--
+-- Runs in place of OverworldState:handleInput while first person drives
+-- (see install below), which means it inherits every gate the grid walk
+-- has: never during scripted moves, transitions, or with anything above
+-- the overworld on the stack.
+
+function FreeMove.tick(state)
+  local p = state.player
+
+  -- a grid move is animating -- a ledge hop, a spinner slide, a scripted
+  -- walk -- or a cutscene owns the player: stand aside, adopt the result
+  if p.moving or p.inputLocked then
+    FreeMove.drop()
+    return
+  end
+  if not pos or p.px ~= lastPx or p.py ~= lastPy then adopt(p) end
+
+  local Game = require("src.core.Game")
+  local input = Game.input
+
+  -- the head is the facing: what A talks to, what the sun's card shows,
+  -- which way a bonk points
+  p.facing = FirstPerson.compassFacing()
+
+  if input:wasPressed("a") then
+    state:interact()
+    return
+  end
+  if input:wasPressed("start") then
+    require("src.core.Sound").play(Game.data, "Start_Menu")
+    require("src.ui.Screens").push(Game, "StartMenu")
+    return
+  end
+
+  local mx, mz = FirstPerson.moveVector()
+  local wx, wz = FirstPerson.moveWorld(mx, mz)
+
+  -- Cycling Road's downhill pull, the free-walk restatement of the grid
+  -- path's simulated PAD_DOWN: south drift with nothing held, braked by
+  -- holding A or B exactly as the Route 17 sign promises
+  local moving = (mx ~= 0 or mz ~= 0)
+  if not moving and Game.save and Game.save.onBike then
+    local fm = Game.data.field.forcedMovement
+    local braking = input:isDown("a") or input:isDown("b")
+    if fm and not braking then
+      for _, m in ipairs(fm.slopeMaps or {}) do
+        if m == state.map.id then
+          wx, wz, moving = 0, 1, true
+          break
+        end
+      end
+    end
+  end
+
+  if not moving then return end
+
+  state.bumpCooldown = math.max(0, (state.bumpCooldown or 0) - 1)
+
+  local speed = (Game.save and Game.save.onBike) and FreeMove.BIKE
+                or FreeMove.WALK
+  local dx, dz = wx * speed, wz * speed
+
+  local hitX = slideX(state, p, dx)
+  local hitZ = slideZ(state, p, dz)
+
+  -- the walk cycle: the wall-bonk clock animates the legs of a player the
+  -- grid thinks is standing still, refreshed while the free walk covers
+  -- ground (Player:update ticks animClock off it; walkPhase reads it)
+  p.bumpFrames = 2
+
+  p.px, p.py = pos.x - 8, pos.z - 8
+  lastPx, lastPy = p.px, p.py
+
+  -- the cell the body stands in; crossing into a new one IS a step
+  local ncx = math.floor(pos.x / 16)
+  local ncy = math.floor(pos.z / 16)
+  if ncx ~= p.cellX or ncy ~= p.cellY then
+    p.cellX, p.cellY = ncx, ncy
+    state:onStepComplete()
+    -- a warp or a battle may have moved the world out from under the
+    -- walk; the adopt check on the next tick picks the pieces up
+    return
+  end
+
+  -- a firm push into something that refused: the engine's own blocked-step
+  -- verbs, aimed the way the push leans
+  local hit, dir
+  if hitX and (not hitZ or math.abs(dx) >= math.abs(dz)) then
+    hit, dir = hitX, (dx > 0 and "right" or "left")
+  elseif hitZ then
+    hit, dir = hitZ, (dz > 0 and "down" or "up")
+  end
+  if hit and math.max(math.abs(dx), math.abs(dz)) > 0.4 * speed then
+    if pushSpecials(state, dir, hit) then
+      FreeMove.drop()
+      return
+    end
+    -- the push handlers may have turned the facing; the head still rules
+    p.facing = FirstPerson.compassFacing()
+  end
+end
+
+-- ------- the seam
+--
+-- OverworldState:handleInput is the one choke point where the grid walk
+-- reads the pad -- the same seam the engine's own Cycling Road pull and
+-- collision warps live behind -- so replacing the walk means wrapping it
+-- and nothing else. Every gate ABOVE the call (scripted moves, trainer
+-- engagement, transitions, anything on the stack) still applies to the
+-- free walk, because the wrap sits below them all.
+function FreeMove.install()
+  local OverworldState = require("src.world.OverworldController")
+  if OverworldState.dramaticShapeFreeMoveHook then return end
+  local inner = OverworldState.handleInput
+
+  function OverworldState:handleInput()
+    if not FirstPerson.driving() then
+      if pos then
+        -- stepping off the rung: back onto the grid, on the cell the
+        -- free walk stood in
+        local p = self.player
+        p.px, p.py = p.cellX * 16, p.cellY * 16
+        FreeMove.drop()
+      end
+      return inner(self)
+    end
+    return FreeMove.tick(self)
+  end
+
+  OverworldState.dramaticShapeFreeMoveHook = true
+end
+
+return FreeMove

lib/ImageCache.lua

@@ -0,0 +1,65 @@
+-- Voxel world mode: decoded pixels, kept.
+--
+-- Assets.imageData is deliberately uncached upstream -- "pixel-level reads
+-- resolve the same way but stay uncached: the caller keeps the derived
+-- product" (src/render/Assets.lua) -- which is the right contract for the
+-- flat renderer, whose one caller decodes a strip once and keeps the strip.
+--
+-- This mod is not that caller. It reads the same handful of images over and
+-- over, from several places that do not know about each other:
+--
+--   * the tileset atlas, decoded by Structures (its own cache), by
+--     TerrainAtlas twice (the SGB bake and the RED++ rebake), by
+--     TerrainAtlas again to learn a tile's shades, and by GlassMask;
+--   * the FLOWER FRAME files, decoded inside patch() -- which runs every
+--     time the animation step turns over, about three times a second, for
+--     as long as the map is on screen. That one is not a load cost at all,
+--     it is a recurring per-second cost on the render thread, and it was
+--     the single clearest waste the first profile turned up.
+--
+-- So: one table, keyed by the path as the CALLER gave it, holding the
+-- decoded ImageData. Registered with Assets.invalidate so a hot reload
+-- drops it alongside every other downstream cache.
+--
+-- The entries are never evicted by size. That is deliberate and bounded:
+-- what lands here is tileset art and animation frames -- a few dozen small
+-- images for a whole session, tens of kilobytes each -- not per-map bakes,
+-- which have their own eviction in TerrainAtlas.setLive.
+
+-- the mod namespace (see main.lua): V.require loads a sibling module
+local V = ...
+
+local Assets = require("src.render.Assets")
+local Perf = V.require("Perf")
+
+local ImageCache = {}
+
+local cache = {}
+
+-- The decoded pixels for `path`, or nil when it cannot be read.
+--
+-- `false` is cached for an unreadable path, so a missing or corrupt asset
+-- costs one failed decode for the session rather than one per frame -- the
+-- same sticky-failure shape the rest of this mod uses for GPU objects.
+function ImageCache.get(path)
+  if not path then return nil end
+  local hit = cache[path]
+  if hit ~= nil then
+    Perf.count("imageCache.hit")
+    return hit or nil
+  end
+  local t0 = Perf.now()
+  local ok, data = pcall(Assets.imageData, path)
+  Perf.add("ImageCache.decode", t0)
+  Perf.count("imageCache.miss")
+  cache[path] = (ok and data) or false
+  return cache[path] or nil
+end
+
+function ImageCache.invalidate()
+  cache = {}
+end
+
+Assets.register(ImageCache.invalidate)
+
+return ImageCache

lib/Mat4.lua

@@ -6,9 +6,11 @@
 -- here -- translation in the fourth column, m[4]/m[8]/m[12].
 --
 -- Only what the renderer actually needs: a perspective projection (the
--- camera), an orthographic one (the sun's shadow pass), a look-based view,
--- and the translate/rotateY/scale a model matrix is built from. No general
--- inverse, no quaternions.
+-- camera), an orthographic one (the sun's shadow pass), an asymmetric one
+-- (a headset's per-eye frustum), a look-based view, a quaternion rotation
+-- (a headset's pose), and the translate/rotateY/scale a model matrix is
+-- built from. No general inverse -- the VR view inverts its rigid pieces
+-- one at a time.
 
 local Mat4 = {}
 
@@ -62,6 +64,45 @@ function Mat4.rotateX(a)
            0, 0, 0, 1 }
 end
 
+-- The rotation a unit quaternion describes, row-major. The VR rig is what
+-- needs it: an OpenXR eye pose arrives as position + orientation
+-- quaternion, and both the eye's transform and its inverse (the view) are
+-- built from this.
+function Mat4.fromQuat(x, y, z, w)
+  local xx, yy, zz = x * x, y * y, z * z
+  local xy, xz, yz = x * y, x * z, y * z
+  local wx, wy, wz = w * x, w * y, w * z
+  return { 1 - 2 * (yy + zz), 2 * (xy - wz), 2 * (xz + wy), 0,
+           2 * (xy + wz), 1 - 2 * (xx + zz), 2 * (yz - wx), 0,
+           2 * (xz - wy), 2 * (yz + wx), 1 - 2 * (xx + yy), 0,
+           0, 0, 0, 1 }
+end
+
+-- Transpose. For a pure rotation this IS the inverse, which is how the VR
+-- view matrix is assembled without a general 4x4 inverse.
+function Mat4.transpose(m)
+  return { m[1], m[5], m[9], m[13],
+           m[2], m[6], m[10], m[14],
+           m[3], m[7], m[11], m[15],
+           m[4], m[8], m[12], m[16] }
+end
+
+-- Right-handed perspective from an OpenXR-style asymmetric field of view:
+-- four signed HALF-ANGLES off the view axis (left and down negative), onto
+-- GL clip space (z in [-1, 1]). A headset's per-eye frustum is off-centre
+-- -- the nose side is narrower than the temple side -- so the symmetric
+-- perspective() above cannot express it.
+function Mat4.fovProjection(angleLeft, angleRight, angleUp, angleDown,
+                            near, far)
+  local l, r = math.tan(angleLeft), math.tan(angleRight)
+  local u, d = math.tan(angleUp), math.tan(angleDown)
+  local w, h, dz = r - l, u - d, near - far
+  return { 2 / w, 0, (r + l) / w, 0,
+           0, 2 / h, (u + d) / h, 0,
+           0, 0, (far + near) / dz, (2 * far * near) / dz,
+           0, 0, -1, 0 }
+end
+
 -- Right-handed perspective onto GL clip space (z in [-1, 1]).
 function Mat4.perspective(fovY, aspect, near, far)
   local f = 1 / math.tan(fovY / 2)

lib/OverworldBattle.lua

@@ -68,10 +68,81 @@ OverworldBattle.setting = ModSetting.new(OverworldBattle.KEY,
                                          OverworldBattle.LABEL,
                                          { true, false }, { "ON", "OFF" })
 
+-- Whether the VR row is ON -- read lazily, because VR requires modules
+-- that sit above this one. While it is, this mode stops being optional:
+-- the headset's battle seat, the pokedex screen and the effects plane
+-- all assume a fight standing on the world, and a white-field battle
+-- inside a headset is exactly the flat screen VR exists to replace.
+local function vrOn()
+  local ok, vr = pcall(V.require, "VR")
+  return ok and vr and vr.enabled and vr.enabled() or false
+end
+
 function OverworldBattle.enabled()
+  if vrOn() then return true end
   return OverworldBattle.setting:get() and true or false
 end
 
+-- ------- BACK SPRITES: the player's own mon stays on the menu
+--
+-- The staged shot stands BOTH mons on the map, which is the mode's whole
+-- claim -- but it costs the one piece of framing Gen 1 is most recognisable
+-- by: your own Pokemon, seen from behind, sitting on top of the battle menu
+-- with its feet on the box. That silhouette is the series' shot.
+--
+-- So BACK SPRITES is offered as a middle setting rather than a compromise
+-- imposed on everyone. With it on the foe is still geometry standing on its
+-- tile at the far end of the arena, and the player's side goes back to being
+-- the GB's own flat back pic in the GB's own slot: same art, same 2x, same
+-- feet on row 96.
+-- Nothing else about the shot moves -- the arena, the camera and the drift are
+-- solved exactly as they were, so the foe stands where it always stood and the
+-- player's cell is simply empty ground in the foreground.
+--
+-- OFF by default: what the mode advertises is the pair of them out there.
+OverworldBattle.BACK_KEY = "battleBack"
+OverworldBattle.BACK_LABEL = "BACK SPRITES"
+
+OverworldBattle.backSetting = ModSetting.new(OverworldBattle.BACK_KEY,
+                                             OverworldBattle.BACK_LABEL,
+                                             { false, true }, { "OFF", "ON" })
+
+-- Gated on 3D-BTL rather than read alone: with staged battles off there is no
+-- staged shot for a back pic to be pinned in FRONT of, and the engine's own
+-- battle screen already draws exactly this. And held OFF under VR: the
+-- headset stands both mons on the world -- a flat back pic pinned to the
+-- 2D frame would keep your own mon off the arena the battle seat looks at.
+function OverworldBattle.backPinned()
+  if not OverworldBattle.enabled() then return false end
+  if vrOn() then return false end
+  return OverworldBattle.backSetting:get() and true or false
+end
+
+-- Whether a pic is the one drawn in the GB's own slot with its feet on the
+-- text box, rather than geometry standing out on the map.
+--
+-- Exactly the player's side under BACK SPRITES -- its mon, or the trainer back
+-- that holds the slot until "Go!" -- because that is the only pic this mod
+-- ever leaves flat (see drawPicsLayer below). The foe is a billboard on its
+-- tile whichever mode is on, and with the mode off the player's side is one
+-- too, so both of those keep the open bottom that lets the arena through a
+-- stride. What the answer buys is in BattlePics: a pic on the box has nothing
+-- behind its lowest row, so its bottom edge seals.
+-- Read by TRUTHINESS rather than against nil, because sideTexture blanks the
+-- side it is not rendering by setting the field to FALSE (see OFF) and holds
+-- it that way for the whole render -- during which the pic layer runs, and
+-- picImage asks this. A nil test passes a `false` straight through to the
+-- index below, and the error comes out of sideTexture into the pcall that
+-- calls it: the foe's billboard is dropped for the frame and the Pokemon
+-- simply is not there.
+function OverworldBattle.pinnedPic(battle, img)
+  if not (battle and img) then return false end
+  if not OverworldBattle.backPinned() then return false end
+  if img == battle.playerBackPic then return true end
+  local player = battle.player
+  return (player and img == player.sprite) and true or false
+end
+
 -- ------- both mons face you
 --
 -- Standing on a map, seen from in front, a Pokemon showing you its BACK is
@@ -81,6 +152,10 @@ end
 -- through the engine's own pokemon.sprite hook -- the seam that exists for
 -- exactly this, so no battle code has to be touched to get it.
 --
+-- Unless BACK SPRITES is on, the setting that asks for the back pic back:
+-- that mon is drawn in its own slot on the menu, seen from behind, and the
+-- front art would be it turned round to face the player it belongs to.
+--
 -- Answered BEFORE a battle exists, because the battler is built before the
 -- battle is pushed. So it cannot ask whether this fight is staged; it asks
 -- whether one on this map WOULD be -- the row is on, the 3D pass is
@@ -91,6 +166,7 @@ local staged = { mapId = nil, ok = false }
 
 function OverworldBattle.wantsFront()
   if not OverworldBattle.enabled() then return false end
+  if OverworldBattle.backPinned() then return false end
   if not Voxel3D.available() then return false end
   -- required here rather than through the file's own helper: this runs
   -- while a battler is being built, which is before that helper is defined
@@ -140,6 +216,51 @@ OverworldBattle.HUD_RECT = {
   player = { 72, 56, 88, 40 },
 }
 
+-- ------- the box at the bottom, on the same glass
+--
+-- The HUDs got frosted panels because black glyphs on grass are not readable.
+-- The battle's text box and its menu had the opposite problem and the same
+-- cause: they are drawn as an OPAQUE WHITE slab with a black border, which was
+-- the field's own colour when the field was white and is a sheet of paper laid
+-- over the bottom third of the diorama now that it is not.
+--
+-- So the box gets exactly what the HUDs get: the world behind it, blurred to
+-- frosted glass and laid back down translucent, with the border and the text
+-- drawn over it unchanged, and the same brightness verdict flipping the ink
+-- when the ground under it is dark. Only the FILL is taken away -- every glyph
+-- the engine draws inside the box is still the engine's own, in its own place.
+--
+-- These are the boxes BattleState:drawTextArea lays down, as GB-frame rects.
+-- READ-ONLY duplicates of that function's own branches, the same kind of
+-- mirror hudLive is and for the same reason: there is no seam that reports "a
+-- move menu is up", and glass has to go down BEFORE the box that sits on it.
+-- The worst a future engine change can do is frost a rectangle nothing lands
+-- on, or leave a box unfrosted -- never break a battle.
+--
+-- Each rect stops where the next one starts rather than overlapping it: two
+-- panels over the same pixels would frost it twice and leave a visible step
+-- along the seam.
+OverworldBattle.TEXT_RECT = {
+  box = { 0, 96, 160, 48 },       -- Font.drawBox(0, 12, 20, 6), always
+  -- moveSelect's TYPE/PP box, Font.drawBox(0, 8, 11, 5), trimmed to the rows
+  -- above the box above -- its last tile row sits inside that one
+  moves = { 0, 64, 88, 32 },
+  -- mimicSelect's copy menu, Font.drawBox(0, 7, 16, 6), trimmed the same way
+  mimic = { 0, 56, 128, 40 },
+}
+
+function OverworldBattle.textRects(battle)
+  if not battle or battle.blankForAskName then return {} end
+  local r = OverworldBattle.TEXT_RECT
+  local out = { box = r.box }
+  if battle.phase == "moveSelect" then
+    out.moves = r.moves
+  elseif battle.phase == "mimicSelect" then
+    out.mimic = r.mimic
+  end
+  return out
+end
+
 -- ------- the HUDs, out at the window's own edges
 --
 -- The battle screen is 160x144 in the MIDDLE of the window and the world is the
@@ -188,6 +309,17 @@ function OverworldBattle.snapRects(shot)
   return rects, { enemy = ex, player = px }
 end
 
+-- A rect measured in the GB frame, in WORLD-canvas pixels: where the letterbox
+-- blit will actually put it. The text box has not moved anywhere -- it is drawn
+-- where it always was -- but its glass is laid into the world image alongside
+-- the HUDs' (see snapHUDs), which is the surface that reaches the screen a
+-- pixel to a pixel rather than magnified out of a 160x144 canvas.
+local function toWorld(rect, shot)
+  local s = shot.scale
+  return { shot.lx + rect[1] * s, shot.ly + rect[2] * s,
+           rect[3] * s, rect[4] * s }
+end
+
 -- ------- the live battle
 --
 -- nil when no overworld battle is running. Never more than one: battles do
@@ -355,6 +487,23 @@ function OverworldBattle.update(dt)
   -- inside somebody else's frame means putting the frame back afterwards.
   local okTex, textures = pcall(OverworldBattle.textures, session.battle)
   if not okTex then textures = nil end
+  -- stashed for the VR eye pass, which stands these same pics on the map
+  -- in ITS view of the world (VoxelScene's eyes path). Stashed HERE
+  -- because rendering them binds canvases, which the eye pass -- mid-scene
+  -- when it wants them -- must never do; reading a stashed canvas is free.
+  session.textures = textures
+  -- and the move-animation layer, for the same eyes -- rendered only
+  -- while a headset is actually watching, because only the VR world
+  -- pass draws it (the flat screen has the animations in-frame already)
+  session.animTex = nil
+  local okVR, vrOn = pcall(function()
+    local vr = V.require("VR")
+    return vr.active and vr.active() or false
+  end)
+  if okVR and vrOn and session.battle then
+    local okA, anim = pcall(OverworldBattle.animTexture, session.battle)
+    if okA then session.animTex = anim end
+  end
   session.token = (session.token or 0) + 1
   local ok, shot = pcall(BattleScene.render, session.state, session.arena,
                          textures, session.token)
@@ -413,6 +562,104 @@ function OverworldBattle.shot()
   return nil
 end
 
+-- The staged fight's WORLD-side pieces, for a pass that stands the mons in
+-- its own view of the map rather than in the arena's composed shot -- the
+-- VR eyes. Returns the two cards as BattleScene.monCards builds them (yawed
+-- toward whatever Voxel3D.eye is at CALL time, so a per-eye caller gets
+-- per-eye cards), the live textures table (for the hit-flash flag), and the
+-- token the shadow signature keys on. nil while nothing is staged, the
+-- arena is broken, or the pics have not been rendered yet.
+function OverworldBattle.worldCards()
+  if not (session and session.arena and not session.broken) then return nil end
+  local tex = session.textures
+  if not tex then return nil end
+  local host = (session.state and session.state.map) or nil
+  if not host then return nil end
+  local groundY = BattleScene.groundY(host, session.arena)
+  return BattleScene.monCards(session.arena, groundY, tex), tex, session.token
+end
+
+-- The live session's BATTLE STATE, once the pushed battle has been met
+-- (session.battle fills in from the stack in update). The VR quad reads
+-- it to tell "the battle screen is on top" from "a menu is over the
+-- battle" -- the UI-only panel is right for the first and wrong for the
+-- second. nil with no session, a broken one, or a battle not yet pushed.
+function OverworldBattle.battle()
+  if not (session and not session.broken) then return nil end
+  return session.battle
+end
+
+-- The move-animation layer as a texture: the engine's own drawAnimLayer,
+-- rendered UNSHIFTED (slot-authored coordinates) into a GB-sized
+-- transparent canvas of its own. This is what stands the effects up in
+-- the VR eyes' world -- see worldAnim below -- the same move the pics
+-- made through sideTexture: let the engine draw what it always draws,
+-- catch it on a canvas, stand the canvas in the scene.
+local animLayer = nil
+-- the engine's own drawAnimLayer, captured by install(). Declared HERE,
+-- above the function that reads it: a local declared further down the
+-- chunk would leave this function reading a global of the same name --
+-- nil forever, and the effects silently absent from the eyes (the bug
+-- this comment is the tombstone of).
+local innerAnim = nil
+
+function OverworldBattle.animTexture(battle)
+  if not (innerAnim and battle) then return nil end
+  if not (love.graphics and love.graphics.newCanvas) then return nil end
+  if not animLayer then
+    local ok, c = pcall(love.graphics.newCanvas,
+                        BattleScene.GB_W, BattleScene.GB_H)
+    if not (ok and c) then return nil end
+    pcall(c.setFilter, c, "nearest", "nearest")
+    animLayer = c
+  end
+  local g = love.graphics
+  local prevCanvas = g.getCanvas()
+  local ok = pcall(function()
+    g.push("all")
+    g.origin()
+    g.setCanvas(animLayer)
+    g.clear(0, 0, 0, 0)
+    g.setBlendMode("alpha")
+    g.setColor(1, 1, 1, 1)
+    innerAnim(battle, false)
+    g.pop()
+  end)
+  if not ok then pcall(g.pop, g) end
+  if prevCanvas then pcall(g.setCanvas, g, prevCanvas)
+  else pcall(g.setCanvas, g) end
+  return ok and animLayer or nil
+end
+
+-- The staged fight's effects, for the VR eyes: the animation layer plus
+-- the plane to stand it on (BattleScene.fxCard -- anchored so a hit
+-- authored at a slot lands on the mon standing in for that slot). nil
+-- while nothing is staged or no layer was rendered this frame.
+function OverworldBattle.worldAnim()
+  if not (session and session.arena and not session.broken) then return nil end
+  local tex = session.animTex
+  if not tex then return nil end
+  local host = (session.state and session.state.map) or nil
+  if not host then return nil end
+  local groundY = BattleScene.groundY(host, session.arena)
+  local model = BattleScene.fxCard(session.arena, groundY,
+                                   OverworldBattle.ANCHOR)
+  if not model then return nil end
+  return tex, model
+end
+
+-- Where the staged fight STANDS -- the arena and its floor height -- for a
+-- camera that wants to look at it rather than draw it (the VR battle
+-- mount). Answered as soon as the stage exists, textures or not: the
+-- camera should be seated behind the fade before the first pic lands.
+-- nil whenever no fight is staged on the world.
+function OverworldBattle.stage()
+  if not (session and session.arena and not session.broken) then return nil end
+  local host = (session.state and session.state.map) or nil
+  if not host then return nil end
+  return session.arena, BattleScene.groundY(host, session.arena)
+end
+
 function OverworldBattle.invalidate()
   BattleDOF.invalidate()
   BattleHud.invalidate()
@@ -471,6 +718,81 @@ local function withoutBackgroundFill(battle, fn)
   if not ok then error(err, 0) end
 end
 
+-- ------- the box, without its paper
+--
+-- Font.drawBox is a white fill and then six border glyphs, and the fill is the
+-- opaque slab the frosted panel underneath is there to replace. So for the
+-- length of one drawTextArea the white fills are dropped and everything else
+-- -- the border, the text, the cursor, the down arrow -- draws exactly as it
+-- always did, over the glass instead of over paper.
+--
+-- Every fill drawTextArea issues is one of those: the box's own, and the two
+-- eight-pixel cells MoveSelectionMenu wipes back to box white before it writes
+-- the border glyphs that hardware would have overwritten. Both are opaque
+-- white, both are paper, and both go.
+--
+-- The same shim shape as withoutBackgroundFill above, and scoped as tightly:
+-- installed around a single call, removed on the way out including on error,
+-- never live outside a battle frame this mode is drawing.
+local function withoutBoxFill(battle, fn)
+  local g = love.graphics
+  local rectangle = g.rectangle
+  g.rectangle = function(mode, ...)
+    if mode == "fill" then
+      local r, gr, b, a = g.getColor()
+      if r > 0.99 and gr > 0.99 and b > 0.99 and a > 0.99 then return end
+    end
+    return rectangle(mode, ...)
+  end
+  local ok, err = pcall(fn, battle)
+  g.rectangle = rectangle
+  if not ok then error(err, 0) end
+end
+
+-- ------- the hour's light, on a pic that is not geometry
+--
+-- Everything standing in the arena goes through the voxel shader, and that
+-- shader multiplies by the hour's tint: at dusk the whole diorama warms, at
+-- night it goes blue, and the two mons' cards go with it because they are
+-- drawn in the same pass as the ground they stand on.
+--
+-- A back pic pinned to the menu is not in that pass. It is the engine's own
+-- flat blit over the finished shot, so it arrived at noon while the world
+-- behind it was at midnight -- a mon lit by nothing in the frame.
+--
+-- So the tint is applied by hand, to that one draw. Every colour the pics
+-- layer sets is multiplied on its way past, which is the whole of it: the
+-- layer draws the pic with love.graphics.draw and LOVE multiplies by the draw
+-- colour, so tinting the colour tints the pixels -- and the alpha, the faint
+-- slide's fade and the blink's own colour all compose with it rather than
+-- being overwritten.
+--
+-- What this does NOT get is the sun: the cards are shadow-mapped, so one
+-- standing under a tree is darker than the tint alone, and this pic has no
+-- position in the scene to be shadowed at. It carries the hour and not the
+-- weather, which is the part the eye reads.
+local function withTint(tint, fn, ...)
+  if not tint then return fn(...) end
+  local r, g, b = tint[1] or 1, tint[2] or 1, tint[3] or 1
+  if r > 0.999 and g > 0.999 and b > 0.999 then return fn(...) end
+  local gfx = love.graphics
+  local setColor = gfx.setColor
+  gfx.setColor = function(cr, cg, cb, ca, ...)
+    if type(cr) == "table" then
+      return setColor({ (cr[1] or 1) * r, (cr[2] or 1) * g, (cr[3] or 1) * b,
+                        cr[4] }, cg, ...)
+    end
+    if cr == nil then return setColor(cr, cg, cb, ca, ...) end
+    return setColor(cr * r, (cg or 1) * g, (cb or 1) * b, ca, ...)
+  end
+  local ok, err = pcall(fn, ...)
+  gfx.setColor = setColor
+  -- the layer leaves whatever colour it last set, and that one is tinted;
+  -- hand the next caller plain white rather than a dimmed one
+  setColor(1, 1, 1, 1)
+  if not ok then error(err, 0) end
+end
+
 -- ------- the mons, as textures for the 3D pass
 --
 -- The two Pokemon are not composited over the world any more: they are quads
@@ -500,6 +822,8 @@ local texturing = nil
 local texCanvas = {}
 local innerPics = nil                   -- captured by install()
 local innerHUDs = nil                   -- likewise, for the snapped HUD layer
+-- (innerAnim, their sibling, is declared up beside animTexture, which
+-- sits earlier in the chunk than this group and must see the local)
 
 local function texCanvasFor(side)
   local c = texCanvas[side]
@@ -600,11 +924,19 @@ function OverworldBattle.flashing(battle)
 end
 
 -- Both sides, or nil when neither has anything to show.
+--
+-- One side under BACK SPRITES: the player's mon is not standing on the map at all
+-- there, it is on the menu, so it has no card to be a texture for -- and
+-- nothing downstream has to know that. No billboard, and no shadow on the
+-- ground under a mon that is not on it.
 function OverworldBattle.textures(battle)
   if not battle then return nil end
   local out = {}
   local okE, enemy = pcall(OverworldBattle.sideTexture, battle, "enemy")
-  local okP, player = pcall(OverworldBattle.sideTexture, battle, "player")
+  local okP, player = true, nil
+  if not OverworldBattle.backPinned() then
+    okP, player = pcall(OverworldBattle.sideTexture, battle, "player")
+  end
   out.enemy = okE and enemy or nil
   out.player = okP and player or nil
   if not (out.enemy or out.player) then return nil end
@@ -655,11 +987,17 @@ function OverworldBattle.install()
   -- behind it. There is a world back there now, so they are filled here
   -- instead -- see BattlePics, which puts the paper back without touching
   -- the silhouette.
+  --
+  -- The pinned pic is told that its feet are on the box, which is what lets
+  -- the pale-bodied back sprites be filled at all: their bellies leak out
+  -- through an opening too wide to read as a drain, and only the box under
+  -- them settles that it is not a hole. Passed the pre-bake image, because
+  -- that is the one the battle holds a reference to.
   local innerPic = BattleState.picImage
   function BattleState:picImage(img)
     local out = innerPic(self, img)
     if not OverworldBattle.shot() then return out end
-    return BattlePics.filled(out)
+    return BattlePics.filled(out, OverworldBattle.pinnedPic(self, img))
   end
 
   -- While a billboard texture is being rendered both pics are put in the same
@@ -719,10 +1057,44 @@ function OverworldBattle.install()
   -- before this screen is composited at all, so the flat pics layer has
   -- nothing left to do here. Skipped rather than left to draw underneath, or
   -- every Pokemon would appear twice: once on its tile and once in its slot.
+  --
+  -- Except under BACK SPRITES, where the player's side never became geometry and this
+  -- layer is the only thing that draws it. The engine's own onlySide argument
+  -- does the whole job: one call, the player's branches alone, in the slot and
+  -- at the scale the GB always put them -- feet on the box, 2x, back view.
   innerPics = BattleState.drawPicsLayer
-  function BattleState:drawPicsLayer(slide, sx, sy)
-    if self.dramaticShapeShot then return end
-    return innerPics(self, slide, sx, sy)
+  function BattleState:drawPicsLayer(slide, sx, sy, onlySide, skipMenuClip)
+    local shot = self.dramaticShapeShot
+    if not shot then
+      return innerPics(self, slide, sx, sy, onlySide, skipMenuClip)
+    end
+    if OverworldBattle.backPinned() and onlySide ~= "enemy" then
+      -- under the hour's own light, like everything else in the frame -- see
+      -- withTint, and the tint BattleScene hands over with the shot.
+      --
+      -- Except on the wavy path, where the pic is baked into the GRAYSCALE bg
+      -- canvas for the zone pass to colour by region. That pass keys off the
+      -- red channel, and a night tint pulls red down -- it would not darken
+      -- the mon, it would remap it to the wrong shade. SE_WAVY_SCREEN lasts a
+      -- second and the hour survives it fine.
+      local tint = not self.grayPics and shot.tint or nil
+      return withTint(tint, innerPics, self, slide, sx, sy, "player",
+                      skipMenuClip)
+    end
+  end
+
+  -- The battle's text box and its menus, over the frosted glass laid down for
+  -- them rather than over their own white paper -- and their ink flipped with
+  -- the HUD's when the ground under the frame is dark, by the same rule and
+  -- off the same verdict.
+  local innerText = BattleState.drawTextArea
+  function BattleState:drawTextArea()
+    if not self.dramaticShapeShot then return innerText(self) end
+    local battle = self
+    if not self.dramaticShapeDark then return withoutBoxFill(battle, innerText) end
+    BattleHud.flipGlyphs(BattleScene.GB_W, BattleScene.GB_H, function()
+      withoutBoxFill(battle, innerText)
+    end)
   end
 
   -- Move animations are authored against the pics' fixed slots, and a single
@@ -730,7 +1102,7 @@ function OverworldBattle.install()
   -- give them. They ride the average, which is where the pair's centre went
   -- -- a few pixels at most, and it keeps a hit landing on the mon it is
   -- aimed at instead of drifting off it.
-  local innerAnim = BattleState.drawAnimLayer
+  innerAnim = BattleState.drawAnimLayer
   function BattleState:drawAnimLayer(colorized)
     local shot = self.dramaticShapeShot
     if not shot then return innerAnim(self, colorized) end
@@ -740,10 +1112,13 @@ function OverworldBattle.install()
     -- mons' projected positions, less the midpoint of the slots they used to
     -- sit in. A hit still lands on the mon it is aimed at.
     local a = OverworldBattle.ANCHOR
-    local dx = (shot.enemy[1] + shot.player[1]) / 2
-                 - (a.enemy[1] + a.player[1]) / 2
-    local dy = (shot.enemy[2] + shot.player[2]) / 2
-                 - (a.enemy[2] + a.player[2]) / 2
+    -- BACK SPRITES leaves the player's mon exactly where the GB put it, so that side
+    -- contributes no movement at all and the pair's centre has gone half as
+    -- far as the foe's mark did.
+    local px, py = shot.player[1], shot.player[2]
+    if OverworldBattle.backPinned() then px, py = a.player[1], a.player[2] end
+    local dx = (shot.enemy[1] + px) / 2 - (a.enemy[1] + a.player[1]) / 2
+    local dy = (shot.enemy[2] + py) / 2 - (a.enemy[2] + a.player[2]) / 2
     love.graphics.push()
     love.graphics.translate(math.floor(dx + 0.5), math.floor(dy + 0.5))
     local ok, err = pcall(innerAnim, self, colorized)
@@ -876,16 +1251,34 @@ function OverworldBattle.snapHUDs(battle, shot)
   if not (battle and shot and shot.canvas and (shot.scale or 0) > 0) then
     return false
   end
+  -- With a headset live the HUDs stay IN the GB frame -- the classic
+  -- slots, on the glass drawHudPanels lays for the unsnapped path. Both
+  -- of VR's battle screens (the floating panel and the pokedex's) crop
+  -- to the letterbox, and a block snapped out to the window's edge would
+  -- be cropped away with the window around it.
+  local okV, vr = pcall(V.require, "VR")
+  if okV and vr and vr.active and vr.active() then return false end
   local slide = (battle.introSlide or 0) * 4
   local rects, bandX = OverworldBattle.snapRects(shot)
   local enemy, player = OverworldBattle.hudLive(battle, slide)
   local live = {}
   if enemy then live.enemy = rects.enemy end
   if player then live.player = rects.player end
+  -- and the text box's own glass, on the same pass. It stays in the middle of
+  -- the frame where the engine draws it -- only the HUDs were snapped out --
+  -- so its GB rect is mapped into the letterbox rather than to an edge.
+  for key, rect in pairs(OverworldBattle.textRects(battle)) do
+    live[key] = toWorld(rect, shot)
+  end
   -- measured under the SNAPPED rects: the panels are over whatever the world
   -- shows at the window's edges now, which is not what was behind them in the
-  -- middle of the frame
+  -- middle of the frame. ONE verdict over all of them, HUDs and box together,
+  -- for the reason BattleHud.verdict gives: a frame with white glyphs in the
+  -- corner and black ones on the menu reads as a bug rather than as adaptation.
   local dark = BattleHud.verdict(live, shot, true)
+  -- the box's own ink is flipped where the engine draws it, in the GB frame,
+  -- so the answer has to outlive this function (see drawHudPanels)
+  if session then session.dark = dark end
   local layer = OverworldBattle.hudTexture(battle, slide, dark)
   if not layer then return false end
 
@@ -911,23 +1304,29 @@ function OverworldBattle.snapHUDs(battle, shot)
   return true
 end
 
--- Lay the frosted glass down under whichever HUD is about to draw, and
--- record which way the glyphs have to flip.
+-- Lay the frosted glass down under whichever HUD and box are about to draw,
+-- and record which way the glyphs have to flip.
 --
--- The fallback path only: with the HUDs snapped out to the window's edges their
--- panels went with them, and there is nothing left inside the GB frame to lay
--- glass under.
+-- The panels are the fallback path only: normally the HUDs are snapped out to
+-- the window's edges and their glass, and the box's, went into the world image
+-- with them (snapHUDs). The VERDICT is needed either way -- the box's ink is
+-- drawn here, in the GB frame, whichever path laid the glass under it.
 function OverworldBattle.drawHudPanels(battle)
   local shot = battle.dramaticShapeShot
   battle.dramaticShapeDark = nil
-  if not shot or snapped() then return end
+  if not shot then return end
+  if snapped() then
+    battle.dramaticShapeDark = session and session.dark or nil
+    return
+  end
   local slide = (battle.introSlide or 0) * 4
   local enemy, player = OverworldBattle.hudLive(battle, slide)
-  if not (enemy or player) then return end
   local rect = OverworldBattle.HUD_RECT
   local live = {}
   if enemy then live.enemy = rect.enemy end
   if player then live.player = rect.player end
+  for key, r in pairs(OverworldBattle.textRects(battle)) do live[key] = r end
+  if not next(live) then return end
   local dark = BattleHud.verdict(live, shot)
   battle.dramaticShapeDark = dark
   for _, r in pairs(live) do BattleHud.panel(r, shot, dark) end

lib/Perf.lua

@@ -0,0 +1,353 @@
+-- Voxel world mode: the instrumentation core.
+--
+-- Ships DARK. Every entry point is one boolean test away from doing
+-- nothing, and the boolean is false unless a run explicitly asks for
+-- measurement (DS_PERF in the environment, or a ds_perf.flag file in the
+-- save directory for a device that has no environment to set). A mod that
+-- measures itself in every player's session is a mod that costs every
+-- player the measurement, so the default has to be off and the off path
+-- has to be free.
+--
+-- What it measures, and why those three things:
+--
+--   * LABELS -- named spans (a bake, a mesh build, a shader compile),
+--     accumulated as {n, total, max}. `max` is the one that matters: a
+--     bake that costs 40ms ONCE is a visible hitch, and an average hides
+--     it completely.
+--   * FRAMES -- a ring of the last N whole-frame times, stamped once per
+--     rendered frame. Frame time is the only number the player actually
+--     experiences; every label total is a hypothesis about which frames.
+--   * COUNTERS -- plain integers a caller bumps (sun-pass redraws, atlas
+--     rebakes). Cheaper than a span when the question is "how often",
+--     not "how long".
+--
+-- Spans are wall time, and on a GPU that means submission time, not
+-- completion time -- the driver is free to finish the work later. So a
+-- GPU-side saving shows up in the FRAME numbers rather than in the label
+-- for the pass that caused it, and both are reported.
+
+local Perf = {}
+
+local clock = (love and love.timer and love.timer.getTime) or os.clock
+
+-- Read through pcall: the loader's sandbox does not hand a mod `os`, and
+-- instrumentation must never be the reason the mod fails to load. Same
+-- shape as OverworldBattle's DS_BATTLE_DEBUG probe.
+local function envFlag(name)
+  local ok, value = pcall(function() return os.getenv(name) end)
+  if not ok then return nil end
+  if value == nil or value == "" or value == "0" then return nil end
+  return value
+end
+
+local function flagFile()
+  if not (love and love.filesystem and love.filesystem.getInfo) then
+    return false
+  end
+  local ok, info = pcall(love.filesystem.getInfo, "ds_perf.flag")
+  return ok and info ~= nil
+end
+
+Perf.enabled = (envFlag("DS_PERF") ~= nil) or flagFile()
+
+Perf.labels = {}      -- label -> { n, total, max }
+Perf.order = {}       -- insertion order, so a report reads chronologically
+Perf.counters = {}    -- name -> integer
+Perf.frames = {}      -- ring of frame times, seconds
+Perf.frameCount = 0
+Perf.RING = 4096
+
+-- The segment a frame belongs to ("map:ROUTE_1:first"). A benchmark
+-- names the phase it is driving; every frame and every label span
+-- recorded while that name is set is attributed to it, which is what
+-- turns "the walk was slow" into "the walk was slow ONLY on the frames
+-- right after ROUTE_1 came into view".
+Perf.segment = nil
+Perf.segments = {}    -- name -> { frames = {}, labels = {}, order = {} }
+
+local function segmentEntry()
+  local name = Perf.segment
+  if not name then return nil end
+  local s = Perf.segments[name]
+  if not s then
+    s = { name = name, frames = {}, labels = {}, order = {} }
+    Perf.segments[name] = s
+    Perf.segments[#Perf.segments + 1] = s   -- array half preserves order
+  end
+  return s
+end
+
+function Perf.setSegment(name)
+  Perf.segment = name
+  if name then segmentEntry() end
+end
+
+-- ---------------------------------------------------------------- spans
+--
+-- Call shape at the measured site:
+--
+--   local t0 = Perf.now()
+--   ... the work ...
+--   Perf.add("TerrainAtlas.staticAtlas", t0)
+--
+-- When disabled, now() returns nil and add() returns on the nil -- two
+-- function calls and a branch, no table touched, no string built. Sites
+-- that would run thousands of times a frame (per draw call, per vertex)
+-- are still too hot for that and are deliberately NOT instrumented; the
+-- frame ring covers them in aggregate.
+
+function Perf.now()
+  if not Perf.enabled then return nil end
+  return clock()
+end
+
+local function bump(store, order, label, dt)
+  local s = store[label]
+  if not s then
+    s = { n = 0, total = 0, max = 0 }
+    store[label] = s
+    order[#order + 1] = label
+  end
+  s.n = s.n + 1
+  s.total = s.total + dt
+  if dt > s.max then s.max = dt end
+end
+
+function Perf.add(label, t0)
+  if t0 == nil then return end
+  local dt = clock() - t0
+  bump(Perf.labels, Perf.order, label, dt)
+  local seg = segmentEntry()
+  if seg then bump(seg.labels, seg.order, label, dt) end
+end
+
+-- Wrap a function in a table, in place. Used by drivers to instrument
+-- module internals they do not own; the mod's own code calls now()/add()
+-- directly so the label is visible at the site.
+function Perf.wrap(tbl, name, label)
+  local orig = tbl and tbl[name]
+  if not orig then return false end
+  tbl[name] = function(...)
+    if not Perf.enabled then return orig(...) end
+    local t0 = clock()
+    local a, b, c, d = orig(...)
+    Perf.add(label or name, t0)
+    return a, b, c, d
+  end
+  return true
+end
+
+-- ------------------------------------------------------------- counters
+
+function Perf.count(name, by)
+  if not Perf.enabled then return end
+  Perf.counters[name] = (Perf.counters[name] or 0) + (by or 1)
+end
+
+-- --------------------------------------------------------------- frames
+--
+-- Called once per RENDERED frame (the endFrame seam), not once per
+-- logic update: a scripted run can step the game many times per render,
+-- and a frame the player never saw cannot have hitched for them.
+
+local lastFrame = nil
+
+function Perf.frame()
+  if not Perf.enabled then return end
+  local t = clock()
+  if lastFrame then
+    local dt = t - lastFrame
+    local n = Perf.frameCount + 1
+    Perf.frameCount = n
+    Perf.frames[(n - 1) % Perf.RING + 1] = dt
+    local seg = segmentEntry()
+    if seg then seg.frames[#seg.frames + 1] = dt end
+  end
+  lastFrame = t
+end
+
+-- Discard the pending frame stamp: after a long blocking operation the
+-- next frame delta would include it and libel the renderer.
+function Perf.resync()
+  lastFrame = Perf.enabled and clock() or nil
+end
+
+-- ------------------------------------------------------------ reporting
+
+local function percentile(sorted, p)
+  local n = #sorted
+  if n == 0 then return 0 end
+  local i = math.ceil(p * n)
+  if i < 1 then i = 1 end
+  if i > n then i = n end
+  return sorted[i]
+end
+
+-- Frame statistics in MILLISECONDS. p95/p99 rather than the average
+-- because smoothness is a tail property: a run that averages 9ms and
+-- spikes to 60ms four times reads as stuttering, and its average reads
+-- as fine.
+function Perf.frameStats(list)
+  local src = list or Perf.frames
+  local sorted = {}
+  for i = 1, #src do sorted[i] = src[i] * 1000 end
+  table.sort(sorted)
+  local n = #sorted
+  local total = 0
+  for i = 1, n do total = total + sorted[i] end
+  local over16, over33 = 0, 0
+  for i = 1, n do
+    if sorted[i] > 16.7 then over16 = over16 + 1 end
+    if sorted[i] > 33.3 then over33 = over33 + 1 end
+  end
+  return {
+    n = n,
+    avg = n > 0 and total / n or 0,
+    p50 = percentile(sorted, 0.50),
+    p95 = percentile(sorted, 0.95),
+    p99 = percentile(sorted, 0.99),
+    worst = n > 0 and sorted[n] or 0,
+    over16 = over16,
+    over33 = over33,
+  }
+end
+
+function Perf.reset()
+  Perf.labels, Perf.order = {}, {}
+  Perf.counters = {}
+  Perf.frames, Perf.frameCount = {}, 0
+  Perf.segments = {}
+  Perf.segment = nil
+  lastFrame = nil
+end
+
+local function sortedLabels(store, order)
+  local out = {}
+  for _, lbl in ipairs(order) do out[#out + 1] = lbl end
+  table.sort(out, function(a, b) return store[a].total > store[b].total end)
+  return out
+end
+
+function Perf.printReport(title)
+  print(("[perf] ==== %s ===="):format(tostring(title or "report")))
+  local f = Perf.frameStats()
+  print(("[perf] frames n=%d avg=%.2fms p50=%.2f p95=%.2f p99=%.2f worst=%.2f  >16.7ms=%d  >33.3ms=%d")
+    :format(f.n, f.avg, f.p50, f.p95, f.p99, f.worst, f.over16, f.over33))
+  for _, seg in ipairs(Perf.segments) do
+    local s = Perf.frameStats(seg.frames)
+    print(("[perf] seg %-28s n=%4d avg=%6.2f p95=%6.2f p99=%6.2f worst=%7.2f >16.7=%3d >33.3=%3d")
+      :format(seg.name, s.n, s.avg, s.p95, s.p99, s.worst, s.over16, s.over33))
+  end
+  print("[perf] ---- labels (ms, sorted by total) ----")
+  for _, lbl in ipairs(sortedLabels(Perf.labels, Perf.order)) do
+    local s = Perf.labels[lbl]
+    print(("[perf] %-46s n=%6d total=%9.1f max=%8.2f")
+      :format(lbl, s.n, s.total * 1000, s.max * 1000))
+  end
+  local names = {}
+  for k in pairs(Perf.counters) do names[#names + 1] = k end
+  table.sort(names)
+  if #names > 0 then print("[perf] ---- counters ----") end
+  for _, k in ipairs(names) do
+    print(("[perf] %-46s %d"):format(k, Perf.counters[k]))
+  end
+end
+
+-- ------------------------------------------------------------------ json
+--
+-- Hand-rolled rather than pulled from the engine: the report has to be
+-- readable by a diff tool between two runs, and that means stable key
+-- ORDER, which a generic serializer does not promise.
+
+local function q(s)
+  return '"' .. tostring(s):gsub('[%c"\\]', function(c)
+    if c == '"' then return '\\"' end
+    if c == "\\" then return "\\\\" end
+    return ("\\u%04x"):format(c:byte())
+  end) .. '"'
+end
+
+local function num(x)
+  return ("%.4f"):format(x)
+end
+
+local function statsJson(f)
+  return ("{\"n\":%d,\"avg\":%s,\"p50\":%s,\"p95\":%s,\"p99\":%s,\"worst\":%s,\"over16\":%d,\"over33\":%d}")
+    :format(f.n, num(f.avg), num(f.p50), num(f.p95), num(f.p99),
+            num(f.worst), f.over16, f.over33)
+end
+
+local function labelsJson(store, order)
+  local parts = {}
+  for _, lbl in ipairs(sortedLabels(store, order)) do
+    local s = store[lbl]
+    parts[#parts + 1] = ("%s:{\"n\":%d,\"total\":%s,\"max\":%s}")
+      :format(q(lbl), s.n, num(s.total * 1000), num(s.max * 1000))
+  end
+  return "{" .. table.concat(parts, ",") .. "}"
+end
+
+function Perf.toJson(meta)
+  local parts = {}
+  parts[#parts + 1] = "{"
+  parts[#parts + 1] = "\"meta\":{"
+  local m = {}
+  for k, v in pairs(meta or {}) do
+    m[#m + 1] = q(k) .. ":" .. (type(v) == "number" and num(v) or q(v))
+  end
+  table.sort(m)
+  parts[#parts + 1] = table.concat(m, ",") .. "},"
+  parts[#parts + 1] = "\"frames\":" .. statsJson(Perf.frameStats()) .. ","
+  parts[#parts + 1] = "\"segments\":{"
+  local segs = {}
+  for _, seg in ipairs(Perf.segments) do
+    segs[#segs + 1] = q(seg.name) .. ":{\"frames\":"
+      .. statsJson(Perf.frameStats(seg.frames))
+      .. ",\"labels\":" .. labelsJson(seg.labels, seg.order) .. "}"
+  end
+  parts[#parts + 1] = table.concat(segs, ",") .. "},"
+  parts[#parts + 1] = "\"labels\":" .. labelsJson(Perf.labels, Perf.order) .. ","
+  local cs = {}
+  for k, v in pairs(Perf.counters) do cs[#cs + 1] = q(k) .. ":" .. v end
+  table.sort(cs)
+  parts[#parts + 1] = "\"counters\":{" .. table.concat(cs, ",") .. "}"
+  parts[#parts + 1] = "}"
+  return table.concat(parts, "")
+end
+
+-- Written through love.filesystem (the save directory) rather than io:
+-- a driver run and an Android session both have one, and neither is
+-- guaranteed a writable working directory.
+function Perf.write(name, meta)
+  local body = Perf.toJson(meta)
+  if love and love.filesystem then
+    pcall(love.filesystem.createDirectory, "ds_bench")
+    local ok = pcall(love.filesystem.write, "ds_bench/" .. name .. ".json", body)
+    if ok then
+      print("[perf] wrote " .. tostring(love.filesystem.getSaveDirectory())
+            .. "/ds_bench/" .. name .. ".json")
+      return true
+    end
+  end
+  print("[perf] JSON " .. name .. ": " .. body)
+  return false
+end
+
+-- ----------------------------------------------------------- draw stats
+--
+-- love.graphics.getStats() resets per frame, so it is only meaningful
+-- read at the END of a frame -- which is where Perf.frame() runs.
+
+function Perf.drawStats()
+  if not (love and love.graphics and love.graphics.getStats) then return end
+  local s = love.graphics.getStats()
+  Perf.count("stat.drawcalls", s.drawcalls or 0)
+  Perf.count("stat.canvasswitches", s.canvasswitches or 0)
+  Perf.count("stat.shaderswitches", s.shaderswitches or 0)
+  Perf.count("stat.frames", 1)
+  Perf.texturememory = s.texturememory
+  Perf.canvases = s.canvases
+  Perf.images = s.images
+end
+
+return Perf

lib/Pokedex.lua

@@ -0,0 +1,223 @@
+-- VR: the POKEDEX in the player's left hand -- a voxel model of the
+-- series' own field guide, strapped to the tracked grip pose, whose
+-- screen is a real texture the mod can put a picture on.
+--
+-- Why it exists: a staged VR battle needs the 2D battle screen SOMEWHERE
+-- -- the text, the menus, the HP bars are the game -- but a flat panel
+-- floating square in front of the fight hides the fight. A trainer in
+-- the world already has the right prop for "a handheld device with a
+-- screen": look down at the Pokedex in your hand to read the battle,
+-- look up to watch it happen on the map.
+--
+-- THE MODEL is authored here in voxels, in METRES (VOX metres a voxel),
+-- around its own centre, front face +Z -- a red slab with the lens, the
+-- LEDs, the hinge and a d-pad, and a dark bezel the screen sits proud
+-- of. It rides VRRig.propMatrix, the same XR-to-world mapping the eyes
+-- use, so it sits exactly where the hand is and keeps its real size in
+-- every mode: a hand-sized device over the diorama, the same hand-sized
+-- device at life scale in first person and in battle.
+--
+-- THE SCREEN is a separate one-quad mesh drawn with its own texture --
+-- whatever canvas the caller hands `Pokedex.screen` (the VR frame hands
+-- it the front buffer during a battle, cropped by UV to the battle's own
+-- letterbox). No texture leaves the screen dark: a device that is off.
+--
+-- Everything here is passive state plus a draw call; VR.lua decides when
+-- the frame exists (hand tracked, session live) and VoxelScene's eye
+-- pass draws it after the world, so it composites with real depth
+-- against everything else.
+
+-- the mod namespace (see main.lua): V.require loads a sibling module
+local V = ...
+
+local Mat4 = V.require("Mat4")
+local Voxel3D = V.require("Voxel3D")
+local VRRig = V.require("VRRig")
+
+local Pokedex = {}
+
+-- one voxel, in metres: a centimetre-ish grid gives the classic chunky
+-- read at a device you can read a battle off (the body below comes out
+-- about 12 x 19 x 3 cm -- a quarter up from the first, believable size,
+-- because the screen carries every menu and was squint-small in hand)
+Pokedex.VOX = 0.011 * 1.25
+
+-- Where the device sits relative to the GRIP pose, in metres, and how it
+-- is tipped. A full quarter turn forward lays the slab exactly along the
+-- controller's own body -- verified in the headset -- so holding the
+-- controller IS holding the device: raise your fist and the screen faces
+-- you. These two are the whole of the attachment.
+Pokedex.OFFSET = { 0, 0.04, -0.02 }
+Pokedex.TILT = -math.pi / 2      -- radians about X: 90 degrees forward,
+                                 -- flush with the controller
+
+-- body proportions, in voxels
+local W, H, D = 9, 14, 2
+
+-- the palette the body's faces point their UVs at, one texel per colour
+local COLORS = {
+  { 200, 40, 48 },    -- 1 body red
+  { 140, 24, 32 },    -- 2 hinge / shaded red
+  { 64, 132, 244 },   -- 3 the lens blue
+  { 208, 228, 255 },  -- 4 lens glint
+  { 232, 60, 48 },    -- 5 LED red
+  { 248, 216, 64 },   -- 6 LED yellow
+  { 72, 200, 96 },    -- 7 LED green
+  { 46, 46, 54 },     -- 8 bezel / d-pad dark
+  { 24, 24, 30 },     -- 9 the dark screen (the "off" state's face)
+}
+
+local paletteTex = nil          -- one texel per COLORS entry
+local bodyMesh = nil
+local screenMesh = nil
+local screenKey = nil           -- the UV rect screenMesh was built for
+
+local function palette()
+  if paletteTex then return paletteTex end
+  if not (love.image and love.image.newImageData
+          and love.graphics and love.graphics.newImage) then return nil end
+  local ok, data = pcall(love.image.newImageData, #COLORS, 1)
+  if not (ok and data) then return nil end
+  for i, c in ipairs(COLORS) do
+    pcall(data.setPixel, data, i - 1, 0,
+          c[1] / 255, c[2] / 255, c[3] / 255, 1)
+  end
+  local built, img = pcall(love.graphics.newImage, data)
+  if not built then return nil end
+  pcall(img.setFilter, img, "nearest", "nearest")
+  paletteTex = img
+  return img
+end
+
+-- Append one solid box's six faces to `verts`/`indices`: position in
+-- voxels (relative to the device centre), size in voxels, colour by
+-- palette index. Faces carry the mod's own directional shade, so the
+-- slab reads as a solid the way every extruded block here does.
+local function box(verts, indices, x, y, z, w, h, d, color)
+  local u = (color - 0.5) / #COLORS
+  local vox = Pokedex.VOX
+  local ox, oy, oz = (x - W / 2) * vox, (y - H / 2) * vox, (z - D / 2) * vox
+  local sx, sy, sz = w * vox, h * vox, d * vox
+  for face = 1, 6 do
+    local corners = Voxel3D.FACE_CORNERS[face]
+    local shade = Voxel3D.FACE_SHADE[face]
+    local n = #verts / 4
+    for _, c in ipairs(corners) do
+      verts[#verts + 1] = { ox + c[1] * sx, oy + c[2] * sy, oz + c[3] * sz,
+                            u, 0.5, shade }
+    end
+    Voxel3D.pushQuad(indices, n)
+  end
+end
+
+-- the screen's face on the front, in voxels (10:9, the GB frame's shape),
+-- shared by the dark "off" face in the body and the live quad
+local SCREEN = { x = 1.2, y = 4.6, w = 6.6, h = 5.94 }
+
+local function buildBody()
+  if bodyMesh then return bodyMesh end
+  local verts, indices = {}, {}
+  -- the slab, the hinge along the right edge, the lens, the LEDs, the
+  -- d-pad and two chunky buttons -- the classic cover furniture, one box
+  -- each on the front face (z = D..)
+  box(verts, indices, 0, 0, 0, W, H, D, 1)                       -- body
+  box(verts, indices, W - 0.7, 0, 0, 0.7, H, D + 0.15, 2)        -- hinge
+  box(verts, indices, 0.6, H - 2.6, D, 2, 2, 0.5, 3)             -- lens
+  box(verts, indices, 0.9, H - 1.3, D + 0.5, 0.6, 0.5, 0.12, 4)  -- glint
+  box(verts, indices, 3.2, H - 1.6, D, 0.8, 0.8, 0.35, 5)        -- LEDs
+  box(verts, indices, 4.5, H - 1.6, D, 0.8, 0.8, 0.35, 6)
+  box(verts, indices, 5.8, H - 1.6, D, 0.8, 0.8, 0.35, 7)
+  -- the bezel plate the screen sits in, and the dark screen face itself
+  -- (what shows when nothing is on: a device that is off, not a hole)
+  box(verts, indices, SCREEN.x - 0.4, SCREEN.y - 0.4, D,
+      SCREEN.w + 0.8, SCREEN.h + 0.8, 0.4, 8)
+  box(verts, indices, SCREEN.x, SCREEN.y, D + 0.4,
+      SCREEN.w, SCREEN.h, 0.1, 9)
+  -- d-pad below the screen, two crossed bars, and the A/B buttons
+  box(verts, indices, 5.6, 1.1, D, 2.1, 0.7, 0.45, 8)
+  box(verts, indices, 6.3, 0.4, D, 0.7, 2.1, 0.45, 8)
+  box(verts, indices, 1.2, 0.8, D, 1.1, 1.1, 0.45, 5)
+  box(verts, indices, 2.9, 0.8, D, 1.1, 1.1, 0.45, 8)
+  bodyMesh = Voxel3D.newMesh(verts, indices)
+  return bodyMesh
+end
+
+-- The live screen: one quad a hair proud of the dark face, UV-mapped to
+-- `uv` = { u0, v0, u1, v1 } of whatever texture is on it. Rebuilt only
+-- when the UV rect moves (a window resize moving the battle letterbox).
+local function buildScreen(uv)
+  local key = table.concat({ uv[1], uv[2], uv[3], uv[4] }, ":")
+  if screenMesh and screenKey == key then return screenMesh end
+  local vox = Pokedex.VOX
+  local x0 = (SCREEN.x - W / 2) * vox
+  local y0 = (SCREEN.y - H / 2) * vox
+  local x1 = x0 + SCREEN.w * vox
+  local y1 = y0 + SCREEN.h * vox
+  local z = (D / 2 + 0.55) * vox
+  local u0, v0, u1, v1 = uv[1], uv[2], uv[3], uv[4]
+  local verts = {
+    { x0, y0, z, u0, v1, 1 }, { x1, y0, z, u1, v1, 1 },
+    { x1, y1, z, u1, v0, 1 }, { x0, y1, z, u0, v0, 1 },
+  }
+  local indices = {}
+  Voxel3D.pushQuad(indices, 0)
+  local mesh = Voxel3D.newMesh(verts, indices)
+  if mesh then
+    screenMesh, screenKey = mesh, key
+  end
+  return mesh
+end
+
+-- ------- the frame's state, set by VR.lua
+--
+-- nil = no pokedex this frame (no session, no tracked left hand).
+Pokedex.frame = nil
+
+-- Stand the device on a tracked LEFT-HAND pose under the current
+-- XR-to-world mapping (the same pivot/anchor/scale/yaw the eyes got).
+function Pokedex.place(pose, pivot, anchor, scale, yaw)
+  local m = VRRig.propMatrix(pose, pivot, anchor, scale, yaw)
+  m = Mat4.mul(m, Mat4.translate(Pokedex.OFFSET[1], Pokedex.OFFSET[2],
+                                 Pokedex.OFFSET[3]))
+  m = Mat4.mul(m, Mat4.rotateX(Pokedex.TILT))
+  Pokedex.frame = { model = m }
+end
+
+-- What the screen shows: a texture and the UV rect of it to fill the
+-- screen with. nil for a dark screen. Only meaningful after place().
+function Pokedex.screen(tex, u0, v0, u1, v1)
+  if Pokedex.frame and tex then
+    Pokedex.frame.tex = tex
+    Pokedex.frame.uv = { u0 or 0, v0 or 0, u1 or 1, v1 or 1 }
+  end
+end
+
+function Pokedex.clear()
+  Pokedex.frame = nil
+end
+
+-- Draw the device with the scene's own pass (model matrix in world px).
+-- Runs inside VoxelScene's drawScene, per eye; no shadow-caster half --
+-- a UI prop should receive the world's light, not throw shade on it.
+function Pokedex.draw()
+  local f = Pokedex.frame
+  if not f then return end
+  local body = buildBody()
+  local pal = palette()
+  if body and pal then
+    Voxel3D.draw(body, pal, f.model)
+  end
+  if f.tex and f.uv then
+    local screen = buildScreen(f.uv)
+    if screen then
+      Voxel3D.draw(screen, f.tex, f.model)
+    end
+  end
+end
+
+-- window resize / hot reload: every GPU object here is derived and cheap
+function Pokedex.invalidate()
+  paletteTex, bodyMesh, screenMesh, screenKey = nil, nil, nil, nil
+end
+
+return Pokedex

lib/ShadowMap.lua

@@ -130,17 +130,23 @@ local SHADER = [[
   }
 #endif
 #ifdef PIXEL
+  uniform float sprite;   // 1 while the CAST is being drawn; see ShadowMap.sprites
   vec4 effect(vec4 color, Image tex, vec2 tc, vec2 sc) {
     // the same alpha discard the main pass uses: a sprite card casts its
     // silhouette, not its 16x16 bounding box
     if (Texel(tex, tc).a < 0.5) discard;
-    // pack into two channels: the high byte in red, the low in green
+    // pack into two channels: the high byte in red, the low in green.
+    // Blue says WHAT cast this, which costs a channel that was zero anyway
+    // and lets a surface decline one kind of caster -- water does, for the
+    // people (see Water's sunLit).
     float d = clamp(vDepth, 0.0, 1.0) * 255.0;
-    return vec4(floor(d) / 255.0, fract(d), 0.0, 1.0);
+    return vec4(floor(d) / 255.0, fract(d), sprite, 1.0);
   }
 #endif
 ]]
 
+ShadowMap._source = function() return SHADER end   -- named for the suite
+
 local shader = nil            -- nil = untried, false = unavailable
 local canvas = nil            -- nil = untried, false = unavailable
 local canvasRes = 0           -- the edge `canvas` was made at
@@ -440,6 +446,9 @@ function ShadowMap.begin(cx, cy, vw, vh)
   love.graphics.setShader(sh)
   love.graphics.setColor(1, 1, 1, 1)
   pcall(sh.send, sh, "lightVP", "row", ShadowMap.clipVP)
+  -- the world until a cast pass says otherwise, reset per pass so one that
+  -- forgot to put it back cannot leak into the next map's terrain
+  pcall(sh.send, sh, "sprite", 0)
   drawing = true
   ready = false
   return true
@@ -448,6 +457,25 @@ end
 -- Draw one caster. Same signature as Voxel3D.draw minus the camera-ward
 -- pull, which is a trick for the VIEW's depth buffer and would drag a
 -- shadow off whatever throws it.
+-- Whether what is drawn next is one of the CAST -- a walker, an authored
+-- figure, a battle's Pokemon -- rather than part of the world. false for the
+-- length of such a pass, true to put it back.
+--
+-- The map records it per texel (the shader's blue channel) so a surface can
+-- decline that kind of caster, and exactly one does: water. A character
+-- standing at a lake's edge threw a hard cut-out of its own sprite across
+-- the surface, which on something showing the sky and the shoreline reads as
+-- a sticker rather than as a shadow in the water. Everything else -- ground,
+-- roofs, ledges, the characters themselves -- still takes them.
+--
+-- Sent rather than branched, so a caller that forgets to put it back only
+-- mislabels casters rather than losing them; begin() resets it per pass.
+function ShadowMap.sprites(on)
+  if not drawing then return end
+  local sh = getShader()
+  if sh then pcall(sh.send, sh, "sprite", on and 1 or 0) end
+end
+
 function ShadowMap.draw(mesh, texture, model)
   if not (drawing and mesh) then return end
   local sh = getShader()

lib/Sky.lua

@@ -16,11 +16,13 @@
 -- as four stripes. No clouds, nothing moving.
 --
 -- NOTHING IS RESAMPLED, which is the whole of why it is drawn this way. There is
--- no baked 160x144 picture scaled up to the window, no downsized buffer blown
--- back up, no texture of any kind: one full-region rectangle through a shader
--- that answers every pixel from its own canvas coordinate. A pixel of sky is
--- computed at the size it is displayed at, so there is nothing for a filter to
--- soften and nothing to go stale when the window or the zoom changes.
+-- no baked 160x144 picture scaled up to the window and no downsized buffer blown
+-- back up: one full-region rectangle through a shader that answers every pixel
+-- from its own canvas coordinate. A pixel of sky is computed at the size it is
+-- displayed at, so there is nothing for a filter to soften and nothing to go
+-- stale when the window or the zoom changes. The shader does bind one texture,
+-- but it is a palette rather than an image -- the bands, one texel each, sampled
+-- nearest (see rampFor, and why it is not a uniform array).
 --
 -- THE PIXEL GRID follows the zoom for the same reason. Bands and dither cells
 -- are measured in DIORAMA pixels -- the pass's own pixels-per-world-pixel, handed
@@ -51,13 +53,11 @@ local V = ...
 local DayNight = V.require("DayNight")
 local PaletteFX = require("src.render.PaletteFX")
 
-local unpack = table.unpack or unpack
-
 local Sky = {}
 
--- The shader carries a fixed-size array, because a GLSL uniform array is a
--- fixed size; eight leaves headroom over DayNight's six-band phase palettes
--- without paying for more.
+-- The most bands a phase palette may paint with. Eight leaves headroom over
+-- DayNight's six-band ones without paying for more; the ramp the shader reads
+-- them from is built at the width actually used, so the cap costs nothing.
 Sky.MAX_BANDS = 8
 
 -- The checkerboard between bands. DITHER_START is how far down a band it begins,
@@ -78,13 +78,26 @@ Sky.DITHER_START = 0.6
 -- ladder instead of changing character rung by rung.
 Sky.SPAN = 0.23
 
+-- How much ELEVATION the gradient spans above the horizon, in radians, for
+-- a caller that anchors the sky IN SPACE rather than to the frame (the VR
+-- eyes -- see Voxel3D.beginScene). On the flat screen the bands run from
+-- the top edge of the frame down to the horizon, which is right for a
+-- camera whose pitch is the rung's: the frame IS the window on the sky.
+-- A headset's frame is wherever the head points, so glueing the zenith
+-- band to its top edge drags the whole gradient around with the head. An
+-- anchored caller instead hangs the gradient over a fixed slice of sky --
+-- horizon to ELEV_SPAN up -- and hands paint() the canvas row that span's
+-- top lands on this frame (the `top` argument), so tilting the head slides
+-- the frame across a sky that stays put.
+Sky.ELEV_SPAN = math.rad(55)
+
 -- ------- the bands
 --
 -- Top first, each a { r, g, b } in 0..1, as the display mode has them.
 --
 -- Memoised, because this runs once a frame and the answer only moves when the
 -- mode does.
-local cache = { bands = nil, key = {} }
+local cache = { bands = nil, key = {}, ramp = nil }
 
 function Sky.bands()
   local pal = DayNight.palette()
@@ -102,6 +115,11 @@ function Sky.bands()
   end
   if same then return cache.bands end
 
+  -- the ramp is these bands as a texture (see rampFor); a new list is a new
+  -- ramp, and the old one is nothing's to keep
+  if cache.ramp and cache.ramp.release then pcall(cache.ramp.release, cache.ramp) end
+  cache.ramp, cache.rampFor = nil, nil
+
   local bands = {}
   for i = 1, n do
     -- backwards: the palette's darkest rung is the top band
@@ -150,55 +168,115 @@ end
 
 -- ------- the pass
 --
--- One rectangle, one shader, no texture. Every pixel answers for itself from its
--- canvas coordinate, so the sky is drawn at exactly the resolution it is
--- displayed at -- there is no image being scaled and so nothing to be soft.
+-- One rectangle, one shader. Every pixel answers for itself from its canvas
+-- coordinate, so the sky is drawn at exactly the resolution it is displayed at
+-- -- there is no image being scaled and so nothing to be soft. The one texture
+-- bound is the band ramp, which is a PALETTE and not a picture: n texels wide,
+-- sampled nearest, one lookup per pixel (see rampFor).
 --
 -- `cell` quantises BOTH the band edges and the dither: the y a pixel is judged
 -- by is the top of its own cell row, so a whole cell row is one colour and every
 -- edge in the sky lands on the diorama's pixel grid.
 local SHADER_SRC = [[
-#define MAXB %d
-uniform vec3 bands[MAXB];
-uniform int count;
+uniform Image ramp;     // the bands, one texel each, top of the sky first
+uniform float count;    // how many texels wide that ramp is
 uniform float edge;     // the sky's bottom, in canvas pixels
+uniform float top;      // where the deepest band begins, in canvas pixels --
+                        // 0 glues the gradient to the frame (the flat
+                        // screen); an anchored caller passes the row its
+                        // fixed elevation span starts on, often negative
 uniform float cell;     // the diorama's pixel size, in canvas pixels
 uniform float start;    // where the checker begins inside a band
+uniform float axisX;    // the "toward the ground" direction on the canvas:
+uniform float axisY;    // (0,1) for a level camera; a rolled VR eye tips
+                        // it, and edge/top are distances along it
+uniform vec3 rayBase;   // the eye's ray fan (VRRig eyeCamera.skyRay): a
+uniform vec3 rayDu;     // canvas point at fractions (u, v) looks along
+uniform vec3 rayDv;     // base + u*du + v*dv, world axes -- so each pixel
+                        // knows its TRUE elevation and the gradient is a
+                        // real skybox, untouched by any head motion
+uniform float raySpan;  // radians of elevation the gradient covers
+uniform vec2 invSize;   // 1/w, 1/h: canvas pixels to fractions
+uniform float useRay;   // 0 = the flat screen's frame-linear gradient
+uniform float cellAng;  // one checker cell in RADIANS (ray path): the
+                        // dither's own grid, laid on azimuth/elevation so
+                        // the pattern is glued to the SKY -- a screen-cell
+                        // parity flips under every head motion and the
+                        // whole gradient shimmers
 uniform float alpha;
 uniform float glowAmt;  // twilight warmth around the low sun; 0 = none
-uniform vec2 glowPos;   // the sun disc, in canvas pixels
-uniform float glowInvR; // 1 / the glow's reach
+uniform vec2 glowPos;   // the sun disc, in canvas pixels (flat path)
+uniform float glowInvR; // 1 / the glow's reach in pixels (flat path)
+uniform vec3 glowDir;   // the sun's world direction (ray path)
+uniform float glowInvA; // 1 / the glow's reach in radians (ray path)
 uniform vec3 glowColor;
 
-// Indexed through a loop counter, which every GLSL ES compiler accepts for a
-// uniform array; a bare bands[idx] is not portable.
-vec3 bandAt(int idx) {
-  vec3 c = bands[0];
-  for (int i = 1; i < MAXB; i++) {
-    if (i == idx) { c = bands[i]; }
-  }
-  return c;
+// Band `i`, read from its own texel centre. The index is clamped rather than
+// trusted: `pos` below can land exactly on `count` when the arithmetic is
+// carried at mediump -- which is the fragment default on GLSL ES -- and a
+// sample past the last band must be the last band, not whatever is off the
+// end of the image.
+vec3 bandAt(float i) {
+  return Texel(ramp, vec2((clamp(i, 0.0, count - 1.0) + 0.5) / count, 0.5)).rgb;
 }
 
 vec4 effect(vec4 color, Image tex, vec2 tc, vec2 sc) {
-  float n = float(count);
-  float row = floor(sc.y / cell) * cell;              // top of this cell row
-  float pos = clamp(row / max(edge, 1.0), 0.0, 0.999999) * n;
-  float base = floor(pos);
-  int idx = int(base);
-  vec3 c = bandAt(idx);
-  float parity = mod(floor(sc.x / cell) + floor(sc.y / cell), 2.0);
-  if (idx < count - 1 && (pos - base) > start) {
-    if (parity < 0.5) { c = bandAt(idx + 1); }
+  float tn;
+  float parity;
+  float glowD = 2.0;                                  // past the reach
+  if (useRay > 0.5) {
+    // A SKYBOX, computed instead of stored: the pixel's own ray lands in
+    // a cell of the sky's angular grid (azimuth columns and elevation
+    // rows, cellAng square), and EVERYTHING -- the band, the checker's
+    // parity, the glow -- is answered from that cell's centre. The
+    // screen grid quantises nothing here; that is the point. A screen
+    // quantisation of similar pitch laid under the sky grid beats
+    // against it (moire), and every subpixel head motion re-snaps the
+    // beat -- the fizz. Sampled per pixel, the picture is exactly a
+    // nearest-filtered texture on a dome: its cells slide smoothly with
+    // the world and no motion of the head recomputes the pattern. The
+    // one seam, where azimuth wraps behind the camera, is a single cell
+    // column of a dither pattern.
+    vec3 dir = rayBase + rayDu * (sc.x * invSize.x)
+                       + rayDv * (sc.y * invSize.y);
+    float elev = atan(dir.y, length(dir.xz));
+    float ei = floor(elev / cellAng);                 // elevation row
+    if (ei < 0.0) { discard; }                        // below the horizon
+    float ai = floor(atan(dir.x, dir.z) / cellAng);   // azimuth column
+    float elc = (ei + 0.5) * cellAng;                 // the row's centre
+    tn = 1.0 - clamp(elc / max(raySpan, 0.001), 0.0, 1.0);
+    parity = mod(ai + ei, 2.0);
+    if (glowAmt > 0.0) {
+      // the glow by the angle between the CELL's centre direction and
+      // the sun's own, so its rings are pinned to the same sky grid
+      float azc = (ai + 0.5) * cellAng;
+      vec3 cd = vec3(cos(elc) * sin(azc), sin(elc), cos(elc) * cos(azc));
+      glowD = acos(clamp(dot(cd, glowDir), -1.0, 1.0)) * glowInvA;
+    }
+  } else {
+    vec2 cc0 = floor(sc / cell) * cell;               // top of this cell
+    float row = cc0.x * axisX + cc0.y * axisY;        // along the axis
+    if (row > edge) { discard; }                      // below the horizon
+    tn = clamp((row - top) / max(edge - top, 1.0), 0.0, 1.0);
+    parity = mod(floor(sc.x / cell) + floor(sc.y / cell), 2.0);
+    if (glowAmt > 0.0) {
+      vec2 cc = (floor(sc / cell) + 0.5) * cell;
+      glowD = length(cc - glowPos) * glowInvR;
+    }
+  }
+  float pos = tn * count;
+  float base = min(floor(pos), count - 1.0);
+  vec3 c = bandAt(base);
+  if (base < count - 1.0 && (pos - base) > start) {
+    if (parity < 0.5) { c = bandAt(base + 1.0); }
   }
   // The sunset's warmth, radiating from the disc: posterised to a few rungs
   // and checker-dithered between them -- the same 8-bit move as the bands,
   // so the glow reads as painted light rather than as a smooth airbrush --
-  // and measured cell-to-cell, so its rings ride the diorama's own grid.
+  // measured cell-to-cell on the flat frame and angle-to-angle on the
+  // skybox, so its rings ride whichever grid the checker itself is on.
   if (glowAmt > 0.0) {
-    vec2 cc = (floor(sc / cell) + 0.5) * cell;
-    float d = length(cc - glowPos) * glowInvR;
-    float g = glowAmt * pow(clamp(1.0 - d, 0.0, 1.0), 2.0);
+    float g = glowAmt * pow(clamp(1.0 - glowD, 0.0, 1.0), 2.0);
     float lvl = floor(g * 4.0);
     if (g * 4.0 - lvl > 0.5 && parity < 0.5) { lvl += 1.0; }
     c = mix(c, glowColor, min(lvl / 3.0, 1.0) * 0.65);
@@ -207,14 +285,87 @@ vec4 effect(vec4 color, Image tex, vec2 tc, vec2 sc) {
 }
 ]]
 
+-- ------- the ramp
+--
+-- The bands as a one-texel-per-band TEXTURE rather than as a uniform array,
+-- which is what they used to be: `uniform vec3 bands[8]`, filled from Lua and
+-- read through a loop counter. On desktop GL that is as portable as it looks.
+-- On Android it was not. The sky's lower bands came back BLACK -- a hard-edged
+-- strip running from partway down the gradient to the horizon point, with the
+-- moon still drawn correctly over it, and with the haze BELOW the sky (the
+-- palest band again, but delivered by love.graphics.clear instead of by the
+-- array) landing in exactly the right colour. Same colour, two routes, one of
+-- them black: the fault was the array, not the palette.
+--
+-- Which of the ES failure modes it was hardly matters -- a driver that
+-- truncates a partially-filled array, a fragment uniform budget the guaranteed
+-- floor of which is sixteen vectors (eight bands plus the glow plus LOVE's own
+-- built-ins is over it), a reflection that finds bands[0] and nothing after --
+-- because they all have the same shape: slots past the first few read as zero,
+-- and zero is black.
+--
+-- A sampler has none of them. One texture unit replaces eight uniform vectors,
+-- there is no array to index and no budget to overrun, and a texel that does
+-- not exist cannot read as black because the image is built at exactly the
+-- width the shader divides by. Nearest and clamped, so a sample lands on one
+-- band's own colour and an out-of-range one lands on the end band rather than
+-- on nothing.
+--
+-- Rebuilt only when the bands move, which is when the clock or the display
+-- mode does; Sky.bands drops it as it rebuilds the list it is made from.
+local function rampFor(bands)
+  if cache.ramp and cache.rampFor == bands then return cache.ramp end
+  if not (love.image and love.image.newImageData
+          and love.graphics and love.graphics.newImage) then return nil end
+  local n = #bands
+  if n < 1 then return nil end
+  local ok, data = pcall(love.image.newImageData, n, 1)
+  if not (ok and data) then return nil end
+  for i = 1, n do
+    local c = bands[i]
+    pcall(data.setPixel, data, i - 1, 0, c[1], c[2], c[3], 1)
+  end
+  local built, img = pcall(love.graphics.newImage, data)
+  if not (built and img) then return nil end
+  -- nearest: a band is a flat colour, not something to interpolate between.
+  -- clamp: the shader clamps its index too, so this is the second of two
+  -- guards against ever sampling off the end -- and it returns the edge band.
+  pcall(img.setFilter, img, "nearest", "nearest")
+  pcall(img.setWrap, img, "clamp", "clamp")
+  cache.ramp, cache.rampFor = img, bands
+  return img
+end
+
+Sky._rampFor = rampFor            -- named for the suite
+
+-- The band ramp for the CURRENT bands, plus how many texels wide it is --
+-- for a pass that wants to read the same sky this one paints. The water's
+-- reflection is the one caller: it looks the reflected direction up on this
+-- very ramp, so the sky on the lake and the sky over it are one palette,
+-- through one display-mode transform, off one clock.
+--
+-- nil where the ramp could not be built, which is exactly when Sky.paint
+-- falls back to flat bands -- so a driver that loses the gradient loses the
+-- reflected gradient with it rather than showing two different skies.
+function Sky.ramp()
+  local bands = Sky.bands()
+  if not (bands and bands[1]) then return nil end
+  local img = rampFor(bands)
+  if not img then return nil end
+  return img, #bands, bands
+end
+
+-- How far the twilight glow reaches around the disc, in canvas pixels, for
+-- a `w`-wide frame. The same number Sky.paint sends as `glowInvR`.
+Sky.GLOW_REACH = 0.55
+
 local shader = nil            -- nil = untried, false = unavailable
 
 local function getShader()
   if shader == nil then
     shader = false
     if love.graphics and love.graphics.newShader then
-      local ok, sh = pcall(love.graphics.newShader,
-                           SHADER_SRC:format(Sky.MAX_BANDS))
+      local ok, sh = pcall(love.graphics.newShader, SHADER_SRC)
       if ok and sh then
         shader = sh
       elseif V and V.mod and V.mod.log then
@@ -234,13 +385,14 @@ Sky._getShader = getShader        -- named for the suite
 -- The flat fallback: the same bands as solid rectangles, no checker, on the same
 -- quantised edges. For a driver that could not compile the shader -- which is
 -- also every headless run.
-local function paintFlat(w, h, bands, edge, alpha, cell)
+local function paintFlat(w, h, bands, edge, alpha, cell, top)
   local g = love.graphics
   local n = #bands
+  local span = edge - (top or 0)
   local prev = 0
   for i = 1, n do
     local cut = (i == n) and math.min(h, math.ceil(edge))
-                         or math.floor(i / n * edge / cell + 0.5) * cell
+                or math.floor(((top or 0) + i / n * span) / cell + 0.5) * cell
     cut = math.max(prev, math.min(cut, math.min(h, math.ceil(edge))))
     if cut > prev then
       local c = bands[i]
@@ -268,28 +420,52 @@ end
 Sky.DISC_FRAC = 0.030     -- disc radius, as a fraction of the frame height
 Sky.DISC_MIN = 3          -- but never fewer cells than this across a radius
 
--- crater centres as fractions of the radius, so they ride any disc size
-local MOON_CRATERS = { { -0.4, -0.2 }, { 0.2, 0.45 }, { 0.5, -0.4 },
-                       { -0.15, 0.7 }, { 0.05, 0.05 } }
+-- crater centres as fractions of the radius, so they ride any disc size.
+-- Public because the water's reflection draws the same moon (see Water):
+-- one list, so the disc on the lake cannot drift from the one in the sky.
+Sky.MOON_CRATERS = { { -0.4, -0.2 }, { 0.2, 0.45 }, { 0.5, -0.4 },
+                     { -0.15, 0.7 }, { 0.05, 0.05 } }
 
-local function paintDisc(body, edge, cell, w, h)
-  local g = love.graphics
-  if not (body and body.y and g.setScissor) then return end
-  local src = body.moon and DayNight.MOON_COLORS or DayNight.SUN_COLORS
-  local shades = PaletteFX.effectiveColors(src) or src
-  local twilight = (body.glowAmt or 0) > 0.25 and not body.moon
+-- a crater's radius, as a fraction of the disc's -- the r/5 paintDisc uses
+Sky.CRATER_FRAC = 0.2
+
+local MOON_CRATERS = Sky.MOON_CRATERS
+
+-- The disc's four shades as the display mode has them, lightest first.
+-- Shared with the reflection pass, so the sun on the water is the same sun
+-- that is in the sky, in the same mode's palette.
+function Sky.discShades(moon)
+  local src = moon and DayNight.MOON_COLORS or DayNight.SUN_COLORS
+  return PaletteFX.effectiveColors(src) or src
+end
+
+-- Whether this body is the LOOMING low sun -- the sunset exaggeration.
+local function looming(body)
+  return (body.glowAmt or 0) > 0.25 and not body.moon
+end
+
+-- The disc's radius for a `h`-tall frame on a `cell`-pixel grid: in CANVAS
+-- PIXELS, and in whole cells. Sized by the FRAME rather than by the world
+-- (see DISC_FRAC), so a zoom does not swell the sun.
+--
+-- Read by paintDisc below and by the reflection, which needs the same
+-- number in radians -- a disc drawn one size and mirrored another would
+-- read as two different suns.
+function Sky.discRadius(h, cell, body)
+  cell = math.max(1, cell or 1)
   local r = math.max(Sky.DISC_MIN,
                      math.floor(h * Sky.DISC_FRAC / cell + 0.5))
-  -- the low sun looms: the classic sunset exaggeration, and it reads
-  if twilight then r = r + math.max(1, math.floor(r * 0.4)) end
-  -- snap the centre to the cell grid, like everything else in this sky
-  local bx = math.floor(body.x / cell) * cell + cell / 2
-  local by = math.floor(body.y / cell) * cell + cell / 2
-  if by - r * cell > edge then return end     -- wholly below the horizon point
+  if body and looming(body) then r = r + math.max(1, math.floor(r * 0.4)) end
+  return r * cell, r
+end
+
+-- One disc's worth of cell art -- shared verbatim by the screen-space
+-- painter below (the flat screen) and by the BAKE the VR eyes texture
+-- their world-anchored quad with (Sky.discImage). `plot(dx, dy, c)` gets
+-- every kept cell in disc-local cell coordinates and its 0..255 colour.
+local function discCells(r, moon, shades, twilight, plot)
   local core = shades[1]
   local main = shades[twilight and 3 or 2]
-  local sx, sy, sw, sh = g.getScissor()
-  g.setScissor(0, 0, math.ceil(w), math.floor(edge))
   local craterR = math.max(1, math.floor(r / 5))
   for dy = -r, r do
     for dx = -r, r do
@@ -298,7 +474,7 @@ local function paintDisc(body, edge, cell, w, h)
         local c = d <= r * 0.5 and core or main
         -- dithered rim: the outer ring keeps only one parity of its cells
         local keep = d <= r - 0.9 or (dx + dy) % 2 == 0
-        if body.moon then
+        if moon then
           for _, cr in ipairs(MOON_CRATERS) do
             local cdx = dx - math.floor(cr[1] * r + 0.5)
             local cdy = dy - math.floor(cr[2] * r + 0.5)
@@ -307,18 +483,86 @@ local function paintDisc(body, edge, cell, w, h)
             end
           end
         end
-        if keep then
-          g.setColor(c[1] / 255, c[2] / 255, c[3] / 255, 1)
-          g.rectangle("fill", bx + dx * cell - cell / 2,
-                      by + dy * cell - cell / 2, cell, cell)
-        end
+        if keep then plot(dx, dy, c) end
       end
     end
   end
+end
+
+local function paintDisc(body, edge, cell, w, h)
+  local g = love.graphics
+  if not (body and body.y and g.setScissor) then return end
+  local shades = Sky.discShades(body.moon)
+  local twilight = looming(body)
+  local _, r = Sky.discRadius(h, cell, body)
+  -- snap the centre to the cell grid, like everything else in this sky
+  local bx = math.floor(body.x / cell) * cell + cell / 2
+  local by = math.floor(body.y / cell) * cell + cell / 2
+  if by - r * cell > edge then return end     -- wholly below the horizon point
+  local sx, sy, sw, sh = g.getScissor()
+  g.setScissor(0, 0, math.ceil(w), math.floor(edge))
+  discCells(r, body.moon, shades, twilight, function(dx, dy, c)
+    g.setColor(c[1] / 255, c[2] / 255, c[3] / 255, 1)
+    g.rectangle("fill", bx + dx * cell - cell / 2,
+                by + dy * cell - cell / 2, cell, cell)
+  end)
   if sx then g.setScissor(sx, sy, sw, sh) else g.setScissor() end
   g.setColor(1, 1, 1, 1)
 end
 
+-- ------- the disc as a TEXTURE, for the VR eyes
+--
+-- A VR eye must not paint the disc in screen space at all: a canvas-grid
+-- painting re-snaps to different cells every head movement (jitter) and
+-- holds its pattern square to the CANVAS (a rolled or pitched head
+-- watches the sun's face turn). So the same cell art is baked once into
+-- a texture, and Voxel3D hangs it on a quad ANCHORED IN THE WORLD --
+-- projected through the eye's own matrix like any geometry, stable under
+-- every head motion. Rebaked only when the palette or the twilight state
+-- moves the colours.
+local discBake = { key = nil, img = nil }
+
+Sky.DISC_BAKE_R = 9          -- bake radius, in cells
+Sky.DISC_BAKE_PX = 8         -- texture pixels per cell
+
+function Sky.discImage(moon, twilight)
+  if not (love.graphics and love.graphics.newCanvas) then return nil end
+  local shades = Sky.discShades(moon)
+  local key = (moon and "m" or "s") .. (twilight and "t" or "-")
+  for i = 1, math.min(3, #shades) do
+    local c = shades[i]
+    key = key .. ":" .. c[1] .. "," .. c[2] .. "," .. c[3]
+  end
+  if discBake.key == key and discBake.img then return discBake.img end
+  local r, px = Sky.DISC_BAKE_R, Sky.DISC_BAKE_PX
+  local size = (2 * r + 1) * px
+  local ok, canvas = pcall(love.graphics.newCanvas, size, size)
+  if not (ok and canvas) then return nil end
+  pcall(canvas.setFilter, canvas, "nearest", "nearest")
+  local g = love.graphics
+  local done = pcall(function()
+    g.push("all")
+    g.origin()
+    g.setCanvas(canvas)
+    g.clear(0, 0, 0, 0)
+    g.setBlendMode("alpha")
+    discCells(r, moon, shades, twilight, function(dx, dy, c)
+      g.setColor(c[1] / 255, c[2] / 255, c[3] / 255, 1)
+      g.rectangle("fill", (dx + r) * px, (dy + r) * px, px, px)
+    end)
+    g.pop()
+  end)
+  if not done then return nil end
+  discBake.key, discBake.img = key, canvas
+  return canvas
+end
+
+-- Whether this body is the looming low sun, for callers sizing the baked
+-- disc (the same exaggeration paintDisc applies through discRadius).
+function Sky.discLooming(glowAmt, moon)
+  return (glowAmt or 0) > 0.25 and not moon
+end
+
 -- Paint the sky into the bound canvas, filling it from the top edge down to
 -- `horizonY` (or to SPAN of the frame when the horizon is out of it).
 --
@@ -329,16 +573,47 @@ end
 -- the caller's own camera (Voxel3D.skyBody), with the twilight glow riding
 -- along; nil hangs nothing and warms nothing.
 --
+-- `top` anchors the gradient in space rather than to the frame: the canvas
+-- row band 1 starts on (often negative -- above the frame), from a caller
+-- that mapped a fixed elevation span to its own camera (see ELEV_SPAN).
+-- nil or 0 is the flat screen's behaviour: zenith band at the top edge.
+--
+-- `axis` tips the whole painting to a rolled camera's true horizon: a unit
+-- {ax, ay} pointing "toward the ground" on the canvas (Voxel3D.horizonLine),
+-- with `horizonY` and `top` then read as distances ALONG it rather than as
+-- rows. nil is the level default. Only the shader path can tilt; the flat
+-- fallback paints level, which only a headless run ever sees. Under an
+-- axis the DISC is not painted here at all -- the VR caller hangs the
+-- baked disc (Sky.discImage) in the world instead; `body` still carries
+-- the twilight glow into the bands.
+--
+-- `ray` makes the gradient a SKYBOX: the eye's own ray fan (the camera
+-- record's skyRay, from VRRig.eyeCamera), letting every pixel take its
+-- band from its TRUE elevation -- so no motion of the head, on any axis,
+-- moves a band; only the clock does. nil keeps the linear frame gradient
+-- the flat screen has always painted.
+--
 -- Returns false when there is nothing to paint, in which case the caller's flat
 -- fill is the whole sky. That fill is the palest band, so a frame that declines
 -- this looks like a hazy day rather than like a bug.
-function Sky.paint(w, h, sky, horizonY, cell, body)
+function Sky.paint(w, h, sky, horizonY, cell, body, top, axis, ray)
   local bands = sky and sky.bands
   if not (bands and bands[1]) then return false end
   if not (w and h and w > 0 and h > 0) then return false end
   local g = love.graphics
   if not (g and g.rectangle) then return false end
-  local edge = Sky.region(h, horizonY)
+  -- with a ray fan the shader's own per-pixel elevation test is the only
+  -- boundary and the whole frame goes through it; along an axis the
+  -- caller's edge is already the signed distance and has no row to be
+  -- clamped to; level callers keep the SPAN fallback
+  local edge
+  if ray then
+    edge = h
+  elseif axis then
+    edge = horizonY
+  else
+    edge = Sky.region(h, horizonY)
+  end
   if not edge then return false end
   local alpha = sky[4] or 1
   cell = math.max(1, math.floor((cell or 1) + 0.5))
@@ -357,39 +632,97 @@ function Sky.paint(w, h, sky, horizonY, cell, body)
   if g.setBlendMode then g.setBlendMode("alpha") end
 
   local glowAmt = body and not body.moon and (body.glowAmt or 0) or 0
+  -- the skybox glow needs the sun's world DIRECTION (skyBody carries it);
+  -- a body without one has nothing to measure angles against, so no glow
+  if ray and glowAmt > 0 and not (body and body.dx) then glowAmt = 0 end
+  -- the world direction a canvas fraction (u, v) looks along, normalised
+  -- -- for sizing the angular checker and the glow's angular reach below
+  local function rayDirAt(u, v)
+    local b, du, dv = ray.base, ray.du, ray.dv
+    local x = b[1] + du[1] * u + dv[1] * v
+    local y = b[2] + du[2] * u + dv[2] * v
+    local z = b[3] + du[3] * u + dv[3] * v
+    local l = math.sqrt(x * x + y * y + z * z)
+    if l < 1e-9 then return 0, 0, -1 end
+    return x / l, y / l, z / l
+  end
+  local function rayAngle(u0, v0, u1, v1)
+    local ax, ay, az = rayDirAt(u0, v0)
+    local bx, by, bz = rayDirAt(u1, v1)
+    local d = ax * bx + ay * by + az * bz
+    return math.acos(math.max(-1, math.min(1, d)))
+  end
   local sh = getShader()
+  local ramp = sh and rampFor(bands)
+  if not ramp then sh = nil end       -- no ramp, no gradient: paint it flat
   if sh then
     local sent = pcall(function()
-      -- one send per band would be one uniform lookup per band; the array takes
-      -- them all at once, and it must be the LAST argument or Lua truncates the
-      -- unpack to a single value
-      sh:send("bands", unpack(bands))
+      -- the bands arrive as a texture, one texel each, and `count` is that
+      -- texture's width -- see rampFor for why they are not a uniform array
+      sh:send("ramp", ramp)
       sh:send("count", #bands)
       sh:send("edge", edge)
+      sh:send("top", math.min(top or 0, edge - 1))
+      sh:send("axisX", axis and axis[1] or 0)
+      sh:send("axisY", axis and axis[2] or 1)
+      sh:send("useRay", ray and 1 or 0)
+      if ray then
+        sh:send("rayBase", ray.base)
+        sh:send("rayDu", ray.du)
+        sh:send("rayDv", ray.dv)
+        sh:send("raySpan", Sky.ELEV_SPAN)
+        sh:send("invSize", { 1 / w, 1 / h })
+        -- the angular checker's cell: the angle one dither cell spans at
+        -- the frame's centre, so the sky-glued grid comes out the same
+        -- size on screen as the diorama's own pixel grid
+        sh:send("cellAng",
+                math.max(1e-4, rayAngle(0.5, 0, 0.5, 1) * cell / h))
+      end
       sh:send("cell", cell)
       sh:send("start", Sky.DITHER and Sky.DITHER_START or 2)
       sh:send("alpha", alpha)
       sh:send("glowAmt", glowAmt)
       if glowAmt > 0 then
         local gc = body.glowColor or { 248, 224, 168 }
-        sh:send("glowPos", { body.x, body.y })
-        sh:send("glowInvR", 1 / math.max(1, w * 0.55))
+        if ray then
+          -- the glow in ANGLES: its direction is the sun's own, and its
+          -- reach is the same fraction of the view the pixel reach was
+          -- of the frame, so the two paths agree on how wide it looks
+          local dx, dy, dz = body.dx, body.dy, body.dz
+          local l = math.sqrt(dx * dx + dy * dy + dz * dz)
+          sh:send("glowDir", { dx / l, dy / l, dz / l })
+          sh:send("glowInvA", 1 / math.max(
+            1e-3, rayAngle(0, 0.5, 1, 0.5) * Sky.GLOW_REACH))
+        else
+          sh:send("glowPos", { body.x, body.y })
+          sh:send("glowInvR", 1 / math.max(1, w * Sky.GLOW_REACH))
+        end
         sh:send("glowColor", { gc[1] / 255, gc[2] / 255, gc[3] / 255 })
       end
     end)
     if sent then
       g.setShader(sh)
       g.setColor(1, 1, 1, 1)
-      g.rectangle("fill", 0, 0, w, math.min(h, math.ceil(edge)))
+      -- tilted or rayed, the sky's reach is not a row: the full frame
+      -- goes through the shader and the discard is the boundary
+      local rectH = (axis or ray) and h or math.min(h, math.ceil(edge))
+      g.rectangle("fill", 0, 0, w, rectH)
       g.setShader()
     else
       sh = nil
     end
   end
-  if not sh then paintFlat(w, h, bands, edge, alpha, cell) end
+  if not sh then
+    paintFlat(w, h, bands, (axis or ray) and math.min(h, edge) or edge,
+              alpha, cell, math.min(top or 0, edge - 1))
+  end
   -- the disc goes over the glow, under nothing: plain rectangles, so it is
-  -- there whether or not the shader built
-  paintDisc(body, math.min(h, edge), cell, w, h)
+  -- there whether or not the shader built. NOT under an axis or a ray fan:
+  -- those cameras hang the baked disc in the world instead (drawWorldDisc,
+  -- with Sky.discImage)
+  if not (axis or ray) then
+    paintDisc(body, math.min(h, edge), cell, w, h)
+  end
   g.setColor(1, 1, 1, 1)
 
   if g.setBlendMode and blend then g.setBlendMode(blend, blendAlpha) end
@@ -399,9 +732,16 @@ function Sky.paint(w, h, sky, horizonY, cell, body)
 end
 
 -- Drop the compiled shader (window resize, hot reload), so a re-created graphics
--- context builds a new one instead of drawing with a handle from the old.
+-- context builds a new one instead of drawing with a handle from the old. The
+-- ramp is a GPU object on the same context and goes with it.
 function Sky.invalidate()
   shader = nil
+  if cache.ramp and cache.ramp.release then pcall(cache.ramp.release, cache.ramp) end
+  cache.ramp, cache.rampFor = nil, nil
+  if discBake.img and discBake.img.release then
+    pcall(discBake.img.release, discBake.img)
+  end
+  discBake.key, discBake.img = nil, nil
 end
 
 return Sky

lib/TerrainAtlas.lua

@@ -270,7 +270,12 @@ local function readback(image)
   local prev = love.graphics.getCanvas()
   local ok, data = pcall(function()
     local w, h = image:getDimensions()
-    local canvas = love.graphics.newCanvas(w, h)
+    -- dpiscale = 1, or this is not a copy. On a highdpi surface (Android,
+    -- iOS -- see conf.lua) newCanvas takes the surface's scale by default,
+    -- so the atlas would be drawn into a texture 2.75x its size and read
+    -- back magnified -- and every tile coordinate below, which counts in
+    -- eights from the top-left, would land somewhere between two tiles.
+    local canvas = love.graphics.newCanvas(w, h, { dpiscale = 1 })
     love.graphics.setCanvas(canvas)
     love.graphics.clear(0, 0, 0, 0)
     -- straight copy: no blending against the cleared target, no tint from

lib/TileShape.lua

@@ -71,6 +71,21 @@ local FALLBACK_HEIGHTS = {
   -- body builds from the bark rows and the drawn ellipse projects onto
   -- the hull's round top
   stump = 16,
+  -- the same hull cut at both ends, hollowed and tapered: an OPEN bin
+  -- standing on a floor (the Vermilion Gym trash cans).  The drawn mouth
+  -- ellipse projects onto the round top and down the well, the drawn base
+  -- ellipse is ground contact rather than body, and the plan narrows toward
+  -- the floor.  Height is AUTHORED (the profile's can_height, which this
+  -- pin must be kept equal to so anything riding a can lands on its rim) --
+  -- the drawing's own straight run is only a couple of rows, because a GB
+  -- cell spends most of itself on the opening
+  can = 9,
+  -- round scenery drawn ONE cell wide and TWO cells TALL, standing on one
+  -- cell of plot: the Pokemon Centers' potted plants. Carved as one
+  -- 16x32x16 hull in the SOUTH (pot) cell -- the drawing's upper cell is
+  -- the object's height, not its depth. BOTH cells take the class; the
+  -- group build anchors on the north one (Structures.buildCylinders)
+  planter = 32,
   billboard = 16,
   signpost = 16,
   post = 16,
@@ -83,10 +98,18 @@ local FALLBACK_HEIGHTS = {
   bed = 7,
   stool = 8,
   counter = 8,
+  -- the raised back band of low seating: the Center couch's west strip
+  -- is drawn from above like the rest of the couch, but depicts the
+  -- back and arm rising over the 8px seat
+  backrest = 12,
   table = 12,
   desk = 24,
   prop = 16,
   cutout = 16,
+  -- a vehicle drawn SIDE-ON: the showroom bicycles.  Standee height like
+  -- every other cutout pool -- what differs is the thickness (see
+  -- Structures' PINNED_DEPTH)
+  bike = 16,
   console = 16,
   relief = 3,
   bookcase = 32,
@@ -123,6 +146,8 @@ local ART = {
   cylinder = "cylinder",
   canopy = "canopy",
   stump = "cylinder",
+  can = "cylinder",
+  planter = "planter",
   billboard = "billboard",
   -- signposts share the billboard treatment but as their own pool at a
   -- 2-voxel depth: a sign is a thin plate on a stick, and the standard
@@ -145,6 +170,9 @@ local ART = {
   -- profile archetype Structures builds real steps for -- rising flights
   -- for stairs leading up, sunken stairwells for stairs leading down
   bed = "top",
+  -- a backrest's art is the couch seen from above, so like the bed it
+  -- rides the top face of its taller box
+  backrest = "top",
   stool = "billboard",
   -- half-cell furniture: a service counter, a low couch.  One 8px band,
   -- so exactly the drawing's bottom row stands up as the front and
@@ -158,6 +186,13 @@ local ART = {
   desk = "upright",
   prop = "billboard",
   cutout = "billboard",
+  -- a bicycle is a LINE drawing seen side-on, and its negative space --
+  -- the air inside the frame, between the wheel and the fork -- is what
+  -- makes it read as a bicycle at all.  Its own pool at two voxels: any
+  -- thicker and the side faces of neighbouring strokes close those gaps
+  -- from every angle but dead-on, and six of them in a showroom come out
+  -- as one dark lump (which is what the 5px `prop` pool gave)
+  bike = "billboard",
   -- a machine standing on furniture: the billboard treatment with
   -- body, plus the one-object contract `cutout` has -- the drawing is
   -- ringed by the furniture it sits on, and those edges must not be
@@ -176,6 +211,7 @@ local ART = {
 local spec = nil          -- the loaded data file, or false when absent
 local cache = {}          -- tileset id -> resolved shape list
 local figCache = {}       -- tileset id -> parsed figure masks, or false
+local mntCache = {}       -- tileset id -> parsed mounted masks, or false
 local bgCache = {}        -- tileset id -> prop background shades, or false
 
 -- The shape profile ships with the mod (data/voxel_heights.lua) and is read
@@ -295,6 +331,24 @@ function TileShape.forMap(map)
   if cache[id] then return cache[id] end
 
   local heights = TileShape.heights()
+  -- Per-tileset height overrides (a tileset entry's `heights`): the class
+  -- vocabulary is global but the drawings are not -- the DOJO lab tables
+  -- are drawn 6px tall where the default `table` is 12 -- and the height
+  -- a sprite RIDES at (VoxelScene.groundAt) must be the height the art
+  -- actually stands, or the starter balls float over their own table.
+  -- Same gate as the global list: known classes, numbers only.
+  do
+    local s = load()
+    local entry = s and s.tilesets and s.tilesets[id]
+    local over = entry and entry.heights
+    if type(over) == "table" then
+      for class, h in pairs(over) do
+        if type(h) == "number" and FALLBACK_HEIGHTS[class] then
+          heights[class] = h
+        end
+      end
+    end
+  end
   local authored = authoredGroups(id, heights)
   local count = math.floor((tileset.imageWidth or 128) / 8)
                 * math.floor((tileset.imageHeight or 48) / 8)
@@ -405,68 +459,158 @@ end
 -- pixel by pixel (see data/voxel_heights.lua):
 --
 --   figures = { { w      = <tiles across>,
+--                 depth  = <voxels of body; ABSENT for a person>,
+--                 thin   = { rows = <top rows>, depth = <voxels> },
+--                 flat   = { x = { <lx0>, <lx1> }, rows = { <r0>, <r1> } },
 --                 tiles  = { ...w*h tile ids, row-major... },
 --                 under  = { ...w*h ids: what each tile wears once the
 --                            figure is lifted off it... },
 --                 pixels = { ...h*8 strings of w*8 chars, "." = not the
 --                            figure... } } }
 --
--- No class: a figure is always a flat sprite card, drawn the way
--- SpriteBillboards draws a character (see Structures.buildFigures).
+-- No class -- what the entry carries instead is a `depth`, or does not:
+--
+--   WITHOUT one it is a flat sprite card, drawn the way SpriteBillboards
+--   draws a character.  That is the right reading for a PERSON: a Gen 1
+--   figure is a face-on 2D icon, and extruding one reconstructs a body
+--   nobody drew (see Structures.buildFigures).
+--   WITH one it is an OBJECT and gets the standee treatment every other
+--   solid here gets -- a per-pixel slab in world space, standing on the
+--   same furniture the card would have stood on.  The Marts' cash
+--   register is the case: a machine on a counter is a box, not an icon.
+--
+-- Two fields say which parts of such a drawing are NOT the extrusion,
+-- because a solid drawn in one 16x16 GB cell still packs more than one
+-- facing:
+--
+--   `thin` caps the thickness over the mask's top rows, for the part of
+--   the drawing that is not the machine (the register's receipt curl).
+--   `flat` names a rect of the mask that is a TOP-VIEW surface rather
+--   than a face -- the register's keypad, whose keys lie ON its deck.
+--   The rect lays horizontal one voxel proud of whatever the extrusion
+--   leaves below it, at the elevation its BOTTOM row would have had,
+--   with drawn row = depth row 1:1 (the mapping the lab tabletop is
+--   drawn with).  So a drawing whose front elevation is an L reads as
+--   one: body up the side and along the base, keys lying in the notch.
 --
 -- Returned normalized: `mask` as a set keyed by ly * (w * 8) + lx, so
 -- Structures can read it as a bitmap without re-parsing per position.
 -- A malformed entry is dropped rather than half-applied -- a typo in a
 -- mask should leave the couch alone, not carve a hole in it.
+--
+-- `mounted` (below) carries the same four fields, so the parse is shared,
+-- and so are the optional ones that give an authored mask a BODY: `depth`,
+-- `thin` and `flat` above.  `depth` is left nil when unstated, because
+-- absence is meaningful on a figure: no depth means the flat sprite card a
+-- person is drawn as.
+local function authoredMasks(list)
+  local out = {}
+  if type(list) ~= "table" then return out end
+  for _, f in ipairs(list) do
+    local ok = type(f) == "table" and type(f.w) == "number"
+               and type(f.tiles) == "table" and type(f.under) == "table"
+               and type(f.pixels) == "table"
+    local w = ok and math.floor(f.w) or 0
+    local h = (w >= 1) and (#f.tiles / w) or 0
+    ok = ok and w >= 1 and h >= 1 and h == math.floor(h)
+         and #f.under == #f.tiles and #f.pixels == h * 8
+    if ok then
+      for i = 1, h * 8 do
+        local row = f.pixels[i]
+        if type(row) ~= "string" or #row ~= w * 8 then
+          ok = false
+          break
+        end
+      end
+    end
+    if ok then
+      local mask, n = {}, 0
+      for ly = 0, h * 8 - 1 do
+        local row = f.pixels[ly + 1]
+        for lx = 0, w * 8 - 1 do
+          if row:sub(lx + 1, lx + 1) ~= "." then
+            mask[ly * (w * 8) + lx] = true
+            n = n + 1
+          end
+        end
+      end
+      local depth = tonumber(f.depth)
+      local thin = nil
+      if type(f.thin) == "table" and tonumber(f.thin.rows)
+         and tonumber(f.thin.depth) then
+        thin = { rows = math.floor(tonumber(f.thin.rows)),
+                 depth = math.floor(tonumber(f.thin.depth)) }
+      end
+      local flat = nil
+      if type(f.flat) == "table" and type(f.flat.x) == "table"
+         and type(f.flat.rows) == "table" then
+        flat = { x0 = math.floor(f.flat.x[1]), x1 = math.floor(f.flat.x[2]),
+                 r0 = math.floor(f.flat.rows[1]),
+                 r1 = math.floor(f.flat.rows[2]) }
+      end
+      if n > 0 then
+        out[#out + 1] = { w = w, h = h, n = n, mask = mask,
+                          tiles = f.tiles, under = f.under,
+                          depth = depth and math.floor(depth) or nil,
+                          thin = thin, flat = flat }
+      end
+    end
+  end
+  return out
+end
+
 function TileShape.figures(tilesetId)
   local hit = figCache[tilesetId]
   if hit ~= nil then return hit or nil end
 
   local s = load()
   local entry = s and s.tilesets and s.tilesets[tilesetId]
-  local list = entry and entry.figures
-  local out = {}
-  if type(list) == "table" then
-    for _, f in ipairs(list) do
-      local ok = type(f) == "table" and type(f.w) == "number"
-                 and type(f.tiles) == "table" and type(f.under) == "table"
-                 and type(f.pixels) == "table"
-      local w = ok and math.floor(f.w) or 0
-      local h = (w >= 1) and (#f.tiles / w) or 0
-      ok = ok and w >= 1 and h >= 1 and h == math.floor(h)
-           and #f.under == #f.tiles and #f.pixels == h * 8
-      if ok then
-        for i = 1, h * 8 do
-          local row = f.pixels[i]
-          if type(row) ~= "string" or #row ~= w * 8 then
-            ok = false
-            break
-          end
-        end
-      end
-      if ok then
-        local mask, n = {}, 0
-        for ly = 0, h * 8 - 1 do
-          local row = f.pixels[ly + 1]
-          for lx = 0, w * 8 - 1 do
-            if row:sub(lx + 1, lx + 1) ~= "." then
-              mask[ly * (w * 8) + lx] = true
-              n = n + 1
-            end
-          end
-        end
-        if n > 0 then
-          out[#out + 1] = { w = w, h = h, n = n, mask = mask,
-                            tiles = f.tiles, under = f.under }
-        end
-      end
-    end
-  end
+  local out = authoredMasks(entry and entry.figures)
 
   figCache[tilesetId] = (#out > 0) and out or false
   return figCache[tilesetId] or nil
 end
 
+-- Hand-authored MOUNTED objects for one tileset: a thing drawn INTO the
+-- wall band it hangs on, cut out by an explicit pixel mask and stood
+-- proud of the wall's face.
+--
+-- Same authoring problem as `figures` and the same answer -- a class pin
+-- resolves a whole 8x8 tile, and the detector cannot segment a drawing
+-- that has no background margin to flood from.  The Bike Shop's two wall
+-- bicycles are the case: the shop's striped wall panel runs BEHIND them,
+-- and its #555 stripes are a flood boundary, so a silhouette flood comes
+-- back with the stripes attached to the bike.
+--
+-- Two things differ from a figure, and both follow from the object being
+-- an object rather than a character:
+--
+--   it keeps its DRAWN ELEVATION.  A figure stands on its own feet; a
+--   mounted thing sits where the wall band draws it, so a bicycle hung
+--   clear of the floor stays hung.
+--   it has THICKNESS (`depth`, default 2), and it is built in world
+--   space as a per-pixel slab jutting south of the band -- not as a
+--   camera-facing sprite card.  A bicycle drawn side-on is a plane
+--   parallel to the wall, not a face-on icon.
+--
+--   mounted = { { w      = <tiles across>,
+--                 depth  = <voxels it juts into the room>,
+--                 tiles  = { ...w*h tile ids, row-major... },
+--                 under  = { ...w*h ids: what each tile wears once the
+--                            object is lifted off it (the plain panel)... },
+--                 pixels = { ...h*8 strings of w*8 chars, "." = wall... } } }
+function TileShape.mounted(tilesetId)
+  local hit = mntCache[tilesetId]
+  if hit ~= nil then return hit or nil end
+
+  local s = load()
+  local entry = s and s.tilesets and s.tilesets[tilesetId]
+  local out = authoredMasks(entry and entry.mounted)
+
+  mntCache[tilesetId] = (#out > 0) and out or false
+  return mntCache[tilesetId] or nil
+end
+
 -- Which GB shades count as BACKGROUND for a pinned per-pixel prop, per tile
 -- (a tileset entry's prop_bg). Returns tile id -> set of shade names, or nil.
 --
@@ -539,12 +683,30 @@ function TileShape.bookcaseBackfill(tilesetId)
   return mode == "above" and mode or nil
 end
 
+--- Does this tileset's `bookcase` run carry the measured pane RELIEF on
+--- its front (a tileset entry's bookcase_relief)?  Default yes: the class
+--- almost always collapses a shelf, a rack or a display case, and every
+--- one of those seals its contents behind a frame that should stand proud
+--- of them.
+---
+--- A tileset says `bookcase_relief = false` when it borrows the collapse
+--- for something that is NOT a shelf -- the League's gate walls and
+--- pilasters, Bill's transporter drums -- where the drawing's light
+--- regions are the masonry and the barrel, not panes, and sinking them
+--- carves the surface instead of describing it.
+function TileShape.bookcaseRelief(tilesetId)
+  local s = load()
+  local entry = s and s.tilesets and s.tilesets[tilesetId]
+  return not (entry and entry.bookcase_relief == false)
+end
+
 -- Drop the cache: a mod that shadows data/voxel_heights.lua or a tileset
 -- record needs the next lookup to re-resolve (hot reload, mod toggle).
 function TileShape.invalidate()
   spec = nil
   cache = {}
   figCache = {}
+  mntCache = {}
   bgCache = {}
 end
 

lib/VR.lua

@@ -0,0 +1,681 @@
+-- VR: the conductor -- one call per game frame that runs the whole
+-- headset side, and the row that switches it on.
+--
+-- The shape of a VR frame, from the pipeline's update hook (which ticks
+-- every frame whatever is on the stack, which is exactly what a headset
+-- needs -- the world must keep arriving through menus, dialogs and
+-- battles):
+--
+--   poll the runtime's events (begin the session when it says READY)
+--   xrWaitFrame            <- BLOCKS until the headset wants a frame;
+--                             with vsync handed off (set to 0 while the
+--                             session runs) this is what paces the whole
+--                             app at headset rate, while FixedStep keeps
+--                             the game's own logic at its 60 Hz
+--   locate the two eyes
+--   render the world once per eye (VoxelScene.render's `eyes` path:
+--     shared shadow map, shared pose capture, per-eye cameras from VRRig)
+--   blit each eye canvas into its swapchain image (VRGL)
+--   copy the window's front buffer into the UI quad when a menu, dialog,
+--     battle or wipe is what the flat screen is showing
+--   xrEndFrame with the projection layer and/or the quad
+--
+-- WHICH VR YOU GET mirrors the VOXEL ladder, deliberately: on the orbit
+-- rungs the world is a TABLETOP DIORAMA pinned below and ahead of where
+-- your head started -- lean in, walk around it; on 1ST you stand inside
+-- at life scale, the HMD steers FirstPerson's yaw and pitch, and FreeMove
+-- walks where you look exactly as it does on the flat screen. A STAGED
+-- FIGHT takes the camera from both: the headset snaps -- through a fade
+-- to black and back -- to the flat battle's own over-the-shoulder seat
+-- (VRRig.battleMount), and returns the same way when the fight ends;
+-- the 2D battle screen lights up on the POKEDEX in the tracked left
+-- hand (lib/Pokedex.lua) and NO floating panel is submitted at all --
+-- the fight itself owns the view. The flat window keeps
+-- running as the mirror (left eye when the world is up), so menus stay
+-- usable at the desk and every existing input keeps working alongside
+-- the XR controllers.
+--
+-- Failure is a status, never a crash: no runtime, no headset, no GL
+-- interop, or a mid-session loss all land back on the flat screen with
+-- the reason readable off VR.status().
+
+-- the mod namespace (see main.lua): V.require loads a sibling module
+local V = ...
+
+local ModSetting = V.require("ModSetting")
+local Voxel = V.require("VoxelState")
+local Voxel3D = V.require("Voxel3D")
+local VoxelScene = V.require("VoxelScene")
+local FirstPerson = V.require("FirstPerson")
+local BattleCam = V.require("BattleCam")
+local VRRig = V.require("VRRig")
+local VRXR = V.require("VRXR")
+local VRGL = V.require("VRGL")
+local Pokedex = V.require("Pokedex")
+
+local VR = {}
+
+-- the row: plain OFF/ON. No hotkey -- the engine's display keys are
+-- spoken for, and a headset is not something to toggle by accident.
+VR.setting = ModSetting.new("vr", "VR", { false, true }, { "OFF", "ON" })
+
+-- Where the diorama's UI panel floats vs first person's. These are the
+-- FALLBACK screens: wherever the pokedex is up and lit -- first
+-- person's menus, a battle's 2D scene -- no quad is submitted at all
+-- (see updateQuad), and these serve only the diorama and the no-tracked-
+-- controller case.
+local QUAD_DIORAMA = { pos = { 0, 0.1, -1.0 }, width = 0.8 }
+local QUAD_FP = { pos = { 0, 0, -1.4 }, width = 1.1 }
+
+local started = false           -- start() succeeded this enablement
+local failed = nil              -- start() failed; wait for a re-toggle
+local wasOn = false
+local savedVsync = nil
+local fboCache = setmetatable({}, { __mode = "k" })   -- canvas -> GL FBO id
+local mirrorSrc = nil           -- last left-eye canvas, for the window
+local mirrorCanvas = nil
+local status = "off"
+
+-- the diorama's live adjustments: the right stick's zoom (a multiplier on
+-- the model's size) and the grab-drag's height (metres of world travel)
+local zoom = 1
+local heightOff = 0
+local held = {}                 -- GB buttons this module is holding down
+local lastHandY = nil           -- the gripping hand's height, last frame
+
+-- First person's SNAP TURN: the right stick flicked left or right steps
+-- the whole XR-to-world mapping 45 degrees at a time (a smooth software
+-- turn is the classic comfort mistake -- vection with no vestibular
+-- signal; a snap is instant and the head does the rest). The offset
+-- turns the mapping itself, so the eyes, the walk direction and the
+-- pokedex all agree about which way the world now faces.
+local SNAP_TURN = math.rad(45)
+local fpYawOff = 0              -- accumulated snaps, radians
+local snapArmed = true          -- re-arms when the stick returns to centre
+
+local function wrapPi(a)
+  return (a + math.pi) % (2 * math.pi) - math.pi
+end
+
+-- The battle snap, made a FADE rather than a cut: when a fight is staged
+-- on the world (or stops being), black rises over both eyes, the camera
+-- swaps mounts behind it, and black lifts. A teleport inside VR is the
+-- one camera move that should never be SEEN happening -- the world
+-- sliding to a new seat reads as the room moving.
+local FADE_TIME = 0.35          -- seconds each way: out, then back in
+local camMode = "explore"       -- "explore" (diorama / 1ST) or "battle"
+local fadeAlpha = 0             -- the black over the eyes right now
+
+-- The staged fight to look at, if there is one: arena, floor height.
+local function battleStage()
+  local ok, arena, groundY = pcall(function()
+    return V.require("OverworldBattle").stage()
+  end)
+  if not ok then return nil end
+  return arena, groundY
+end
+
+-- the palette closure the engine hands drawWorld; stashed there (see
+-- main.lua) because the VR frame renders from update, where no ctx exists
+VR.paletteFor = nil
+
+-- Whether this platform can do VR AT ALL: the shipped loader and the GL
+-- interop are Win32 (openxr_loader.dll, wgl), so only Windows qualifies.
+-- Everywhere else -- Android above all -- the row is not offered on any
+-- menu, and a stored vr=true is ignored rather than read: a save that
+-- migrated over from the desktop must not leave a phone trying to start
+-- an OpenXR session (or silently forcing the battle rows). Headless runs
+-- have no love.system and answer true, which costs nothing: enabling VR
+-- there stops at VRXR.start like it always did.
+function VR.supported()
+  local ok, os = pcall(function() return love.system.getOS() end)
+  if not ok or not os then return true end
+  return os == "Windows"
+end
+
+function VR.enabled()
+  return VR.supported() and VR.setting:get() == true
+end
+
+function VR.active()
+  return started and VRXR.isRunning()
+end
+
+function VR.status()
+  if not VR.enabled() then return "off" end
+  if failed then return failed end
+  return VRXR.status()
+end
+
+-- Let go of every input this module was holding: the GB buttons pressed
+-- through the overlay path, and the synthetic left stick. Runs when the
+-- session ends and whenever a frame has no controller state to read.
+local function releaseInputs()
+  local ok, Game = pcall(require, "src.core.Game")
+  if not ok or not Game.input then return end
+  for btn in pairs(held) do
+    pcall(function() Game.input:overlayReleased(btn) end)
+    held[btn] = nil
+  end
+  pcall(function()
+    Game.input:gamepadaxis(nil, "leftx", 0)
+    Game.input:gamepadaxis(nil, "lefty", 0)
+  end)
+  lastHandY = nil
+end
+
+local function shutdown(reason)
+  if started then
+    VRXR.stop()
+    started = false
+  end
+  if savedVsync ~= nil then
+    pcall(love.window.setVSync, savedVsync)
+    savedVsync = nil
+  end
+  -- the placed camera may still be a VR eye's; the orbit must get the
+  -- pass back clean
+  Voxel3D.camera = nil
+  mirrorSrc = nil
+  releaseInputs()
+  BattleCam.still = false
+  VoxelScene.spriteLean = nil
+  Pokedex.clear()
+  zoom, heightOff = 1, 0
+  fpYawOff, snapArmed = 0, true
+  camMode, fadeAlpha = "explore", 0
+  status = reason or "off"
+end
+
+VR.shutdown = shutdown          -- named for the probe driver
+
+-- Whether the flat screen is showing something the world pass cannot: a
+-- menu, a dialog, a battle, a transition wipe. The quad and the pokedex's
+-- screen both key on it.
+local function uiShowing()
+  local ok, showing = pcall(function()
+    local Game = require("src.core.Game")
+    local top = Game.stack and Game.stack:top()
+    return top ~= Game.overworld
+           or (Game.overworld and Game.overworld.transitioning) or false
+  end)
+  return ok and showing or false
+end
+
+-- ------- the pokedex's screen
+--
+-- What the device in the hand shows during a battle: the flat window --
+-- which IS the 2D battle screen for as long as the battle state draws --
+-- copied into a canvas the scene pass can texture with, cropped by UV to
+-- the battle's own letterbox so the screen wears the GB frame edge to
+-- edge. Menus over the battle (the party, the bag) ride along for free:
+-- they are the flat screen too, and reading them on the device in your
+-- hand is exactly the point.
+local dexCanvas = nil
+
+local function dexScreen()
+  local ok, out = pcall(function()
+    local ww, wh = love.graphics.getPixelDimensions()
+    if not (ww and ww > 0 and wh and wh > 0) then return nil end
+    if not (dexCanvas and dexCanvas:getWidth() == ww
+            and dexCanvas:getHeight() == wh) then
+      dexCanvas = love.graphics.newCanvas(ww, wh)
+      pcall(dexCanvas.setFilter, dexCanvas, "nearest", "nearest")
+    end
+    local fbo = fboCache[dexCanvas]
+    if not fbo then
+      fbo = VRGL.canvasFBO(dexCanvas)
+      fboCache[dexCanvas] = fbo
+    end
+    if not (fbo and VRGL.copyFrontToCanvas(fbo, ww, wh)) then return nil end
+    local BattleScene = V.require("BattleScene")
+    local lx, ly, s = BattleScene.letterbox()
+    return { dexCanvas,
+             lx / ww, ly / wh,
+             (lx + BattleScene.GB_W * s) / ww,
+             (ly + BattleScene.GB_H * s) / wh }
+  end)
+  return ok and out or nil
+end
+
+-- ------- the world, once per eye
+
+local function renderWorld(views, ctl)
+  local ok, Game = pcall(require, "src.core.Game")
+  local ow = ok and Game.overworld or nil
+  if not (ow and ow.map and ow.camera and Voxel.active()
+          and Voxel3D.available()) then
+    return false
+  end
+  local vw, vh = 320, 288
+  pcall(function() vw, vh = Game.renderer:worldViewSize() end)
+
+  -- Whatever the camera does, the CARDS hold the top rung's near-upright
+  -- lean: a head that roams has no one pitch for them to match, and 75
+  -- degrees is the pose that reads as "standing" from anywhere. Cleared
+  -- on shutdown, so the flat screen leans with the rung as ever.
+  VoxelScene.spriteLean = math.rad(75)
+
+  local pivot, anchor, scale, mountYaw
+  local fp = FirstPerson.engaged()
+  local battle, battleFloor
+  if camMode == "battle" then battle, battleFloor = battleStage() end
+  if battle then
+    -- the over-the-shoulder seat the flat battle shot stands in, pulled
+    -- close enough for a headset's own lens (see VRRig.battleMount), at
+    -- life scale, turned to face the arena
+    local rec = BattleCam.rig(battle, battleFloor)
+    pivot, mountYaw = VRRig.battleMount(rec.eye, rec.focus)
+    anchor = { 0, 0, 0 }
+    scale = VRRig.FP_SCALE
+  elseif fp then
+    local p = ow.player
+    local gh = 0
+    pcall(function() gh = VoxelScene.groundAt(ow.map, p.cellX, p.cellY) end)
+    pivot = VRRig.fpPivot(p.px, p.py, gh, FirstPerson.EYE_HEIGHT)
+    anchor = { 0, 0, 0 }
+    scale = VRRig.FP_SCALE
+    -- the snap turn is a yaw on the MAPPING, same seam the battle mount
+    -- turns through
+    if fpYawOff ~= 0 then mountYaw = fpYawOff end
+    -- the HMD is the head: its yaw and pitch (plus the snaps) become
+    -- FirstPerson's, so FreeMove walks where you look and A talks to
+    -- what you face
+    local yaw, pitch = VRRig.headYawPitch(views[1].pose.quat)
+    FirstPerson.yaw = wrapPi(yaw + fpYawOff)
+    FirstPerson.pitch = math.max(FirstPerson.PITCH_UP,
+                          math.min(FirstPerson.PITCH_DOWN, pitch))
+  else
+    -- The table presents the world exactly as the flat screen does at
+    -- rest: the pivot sits VIEW_DIST away along the RUNG'S own angle
+    -- (stepping rungs re-tilts the model, easing with the rung tween),
+    -- at the scale that reproduces the flat framing -- then the player's
+    -- own adjustments go on top: the stick's zoom, the grip's height.
+    pivot = VRRig.dioramaPivot(ow.camera.x + vw / 2, ow.camera.y + vh / 2)
+    anchor = VRRig.dioramaAnchor(Voxel.angle, heightOff)
+    scale = VRRig.dioramaScale(vh, Voxel.FOCAL) / zoom
+  end
+
+  -- The pokedex, on the tracked left hand, under this very mapping --
+  -- but only where it earns its keep: FIRST PERSON, where its screen is
+  -- every menu, dialog and wipe the flat screen shows (and the floating
+  -- billboard is retired outright -- see updateQuad), and the BATTLE
+  -- seat, where its screen is the fight's own 2D scene. The diorama
+  -- does without: a hand-sized device hovering over a tabletop town is
+  -- clutter, and the panel serves there. No hand tracked, no device.
+  local hand = ctl and ctl.handl or nil
+  if hand and (battle or fp) then
+    Pokedex.place(hand, pivot, anchor, scale, mountYaw)
+    if uiShowing() then
+      local scr = dexScreen()
+      if scr then
+        Pokedex.screen(scr[1], scr[2], scr[3], scr[4], scr[5])
+      end
+    end
+  else
+    Pokedex.clear()
+  end
+
+  local eyes = {}
+  for i = 1, 2 do
+    local v = views[i]
+    eyes[i] = {
+      camera = VRRig.eyeCamera(v.pose, v.fov, pivot, anchor, scale, mountYaw),
+      w = v.w, h = v.h,
+      slot = i == 1 and "vrL" or "vrR",
+      -- the battle seat is a placed shot, not the first-person rig: the
+      -- cards keep their stage lean rather than yawing at this eye, and
+      -- the player's own card stays visible in it
+      adopt = not battle,
+    }
+  end
+  eyes.cx, eyes.cy = pivot[1], pivot[3]
+
+  local okR, canvases = pcall(VoxelScene.render, ow, 0, 0, vw, vh,
+                              VR.paletteFor, eyes)
+  if not (okR and type(canvases) == "table" and canvases[1] and canvases[2])
+  then
+    return false
+  end
+
+  -- the snap's fade, over the finished eyes: plain black at this moment's
+  -- strength, drawn before the blit so the headset never sees the swap
+  if fadeAlpha > 0 then
+    pcall(function()
+      for i = 1, 2 do
+        local c = canvases[i]
+        love.graphics.setCanvas(c)
+        love.graphics.setColor(0, 0, 0, math.min(1, fadeAlpha))
+        love.graphics.rectangle("fill", 0, 0, c:getWidth(), c:getHeight())
+      end
+      love.graphics.setCanvas()
+      love.graphics.setColor(1, 1, 1, 1)
+    end)
+  end
+
+  for i = 1, 2 do
+    local canvas = canvases[i]
+    local tex, tw, th = VRXR.acquireEye(i)
+    if tex then
+      local fbo = fboCache[canvas]
+      if not fbo then
+        fbo = VRGL.canvasFBO(canvas)
+        fboCache[canvas] = fbo
+      end
+      if fbo then
+        VRGL.blitToTexture(fbo, canvas:getWidth(), canvas:getHeight(),
+                           tex, tw, th)
+      end
+    end
+    VRXR.releaseEye(i)
+  end
+  mirrorSrc = canvases[1]
+  return true
+end
+
+-- ------- the UI panel
+
+-- Whether the flat screen is showing something the world pass cannot: a
+-- menu, a dialog, a battle, a transition wipe -- or everything, when the
+-- world pass is off entirely.
+local function wantQuad(worldUp)
+  if not worldUp then return true end
+  return uiShowing()
+end
+
+local function updateQuad(worldUp, fp)
+  if not wantQuad(worldUp) then return nil end
+  -- Wherever the pokedex is up and lit -- first person's menus, the
+  -- battle seat's 2D fight -- it IS the screen, and no floating
+  -- billboard is submitted at all. (No tracked left hand still gets
+  -- the panel: the UI must be readable somewhere.)
+  if Pokedex.frame and Pokedex.frame.tex then return nil end
+  local tex, qw, qh = VRXR.acquireQuad()
+  if not tex then return nil end
+  local ww, wh = qw, qh
+  pcall(function() ww, wh = love.graphics.getPixelDimensions() end)
+  -- The panel wears the GB FRAME, not the window: everything the flat
+  -- screen has to say lives in the 160x144 letterbox (the world around
+  -- it is just the mirror's picture). The frame region is blitted OUT
+  -- of the window and SCALED into the swapchain image -- never copied
+  -- pixel-for-pixel, because the swapchain's size is fixed at session
+  -- start and a fullscreened window outgrows it, running the frame (and
+  -- the START menu flush with its right edge) off the copy. Scaled, the
+  -- panel shows the identical picture at the identical ratio whatever
+  -- size the window is. Source coordinates are GL's, origin bottom-left.
+  local crop = nil
+  local copied = false
+  pcall(function()
+    local BattleScene = V.require("BattleScene")
+    local lx, ly, s = BattleScene.letterbox()
+    local wpx = math.ceil(BattleScene.GB_W * s)
+    local hpx = math.ceil(BattleScene.GB_H * s)
+    local sx = math.max(0, math.floor(lx))
+    local sy = math.max(0, math.floor(wh - ly - hpx))
+    wpx = math.min(wpx, ww - sx)
+    hpx = math.min(hpx, wh - sy)
+    if wpx < 1 or hpx < 1 then return end
+    -- fitted to the swapchain image at the REGION's own aspect: the
+    -- crop then presents exactly that rect, so the panel's shape is the
+    -- GB frame's at any window and any swapchain size
+    local fit = math.min(qw / wpx, qh / hpx)
+    local dw = math.max(1, math.floor(wpx * fit))
+    local dh = math.max(1, math.floor(hpx * fit))
+    if VRGL.copyFrontRegionToTexture(tex, sx, sy, wpx, hpx, dw, dh) then
+      copied = true
+      crop = { 0, 0, dw, dh }
+    end
+  end)
+  if not copied then
+    -- no letterbox to cut (or the blit refused): the old whole-window
+    -- copy, clamped, is still a readable panel
+    VRGL.copyFrontBuffer(tex, math.min(qw, ww), math.min(qh, wh))
+  end
+  VRXR.releaseQuad()
+  local base = fp and QUAD_FP or QUAD_DIORAMA
+  if not crop then return base end
+  return { pos = base.pos, width = base.width, crop = crop }
+end
+
+-- ------- the controllers
+--
+-- The mapping the mod ships (rebindable in the runtime's own UI):
+--
+--   both modes    left stick moves (through the engine's own stick path,
+--                 so it grid-walks the diorama and free-walks 1ST);
+--                 A/B are A/B; either trigger is START; clicking the
+--                 LEFT stick steps the VOXEL angle ladder exactly as
+--                 the "3" key (and the pad's SELECT) does.
+--   1ST only      right stick left/right SNAP-TURNS 45 degrees a flick.
+--   diorama only  right stick up/down zooms the model; squeezing a grip
+--                 and moving that hand up or down drags the whole table
+--                 with it.
+--
+-- Leaving VR is the VR row's job alone (OPTIONS menu or the manager) --
+-- no controller button does it. VR.leave below stays as the API for it.
+
+-- The left stick click makes EXACTLY the step the "3" key makes: one
+-- rung up the VOXEL angle ladder, wrapping, stepping over FULL, clearing
+-- TILT and GBC FX in the save -- by calling the very function the key
+-- and the pad's SELECT button already share. main.lua installs it below
+-- (cycleVoxel is a local of that file); the free-roam gate is the
+-- registry's own, inside it, so a click over a menu or mid-warp is a
+-- no-op exactly like the key.
+VR.cycleVoxel = nil             -- cycleVoxel(game), set by main.lua
+
+function VR.stepView()
+  pcall(function()
+    if not VR.cycleVoxel then return end
+    VR.cycleVoxel(require("src.core.Game"))
+  end)
+end
+
+-- Leave VR: the VR row toggled back off and persisted, exactly as if
+-- stepped on the OPTIONS menu, so the next update tears the session down
+-- and the flat screen takes the picture back. Deliberately bound to NO
+-- controller button (a click that ejects you from the headset is a trap
+-- mid-fight); kept as the one programmatic door out.
+function VR.leave()
+  pcall(function()
+    local Game = require("src.core.Game")
+    VR.setting:setIndex(VR.setting:read() + 1, Game)
+  end)
+end
+
+local function setGB(inp, btn, down)
+  if down and not held[btn] then
+    held[btn] = true
+    inp:overlayPressed(btn)
+  elseif not down and held[btn] then
+    held[btn] = nil
+    inp:overlayReleased(btn)
+  end
+end
+
+local function driveControls(ctl, dt, fp)
+  if not ctl then
+    releaseInputs()
+    return
+  end
+  local ok, Game = pcall(require, "src.core.Game")
+  if not (ok and Game.input) then return end
+  local inp = Game.input
+
+  setGB(inp, "a", ctl.a)
+  setGB(inp, "b", ctl.b)
+  setGB(inp, "start", ctl.start)
+
+  -- the left stick, through the engine's OWN stick handler: it quantises
+  -- to the grid d-pad for the diorama, and FirstPerson.moveVector reads
+  -- the same raw pair for the free walk. OpenXR's +Y is up; the engine's
+  -- lefty is +down.
+  inp:gamepadaxis(nil, "leftx", ctl.moveX or 0)
+  inp:gamepadaxis(nil, "lefty", -(ctl.moveY or 0))
+
+  if ctl.toggleChanged and ctl.toggle then VR.stepView() end
+
+  -- first person's snap turn: a flick of the right stick steps the view
+  -- 45 degrees, once per flick -- it re-arms only when the stick comes
+  -- back toward centre, so holding it turns exactly once
+  if fp and camMode ~= "battle" then
+    local sx = ctl.lookX or 0
+    if math.abs(sx) > 0.65 then
+      if snapArmed then
+        snapArmed = false
+        -- increasing yaw turns LEFT in this mod's compass, so a stick
+        -- pushed right subtracts
+        fpYawOff = wrapPi(fpYawOff + (sx > 0 and -SNAP_TURN or SNAP_TURN))
+      end
+    elseif math.abs(sx) < 0.35 then
+      snapArmed = true
+    end
+  end
+
+  if not fp and camMode ~= "battle" then
+    local zy = ctl.lookY or 0
+    if math.abs(zy) > 0.15 then
+      zoom = math.max(0.35, math.min(4, zoom * math.exp(zy * (dt or 0) * 1.6)))
+    end
+    -- the grab-drag: while a grip is squeezed, the table follows that
+    -- hand's height, metre for metre
+    local gl, gr = ctl.gripL or 0, ctl.gripR or 0
+    local y = (gr >= gl) and ctl.handrY or ctl.handlY
+    if math.max(gl, gr) > 0.6 and y then
+      if lastHandY then
+        heightOff = math.max(-1.5, math.min(1.5, heightOff + (y - lastHandY)))
+      end
+      lastHandY = y
+    else
+      lastHandY = nil
+    end
+  else
+    lastHandY = nil
+  end
+end
+
+-- ------- the per-frame drive
+
+function VR.update(dt)
+  local on = VR.enabled()
+  if not on then
+    if wasOn then
+      shutdown("off")
+      failed = nil
+    end
+    wasOn = false
+    return
+  end
+
+  if not wasOn then failed = nil end   -- a fresh toggle earns a fresh try
+  wasOn = true
+  if failed then return end
+
+  if not started then
+    local qw, qh = 1024, 768
+    pcall(function() qw, qh = love.graphics.getPixelDimensions() end)
+    if VRXR.start(qw, qh) then
+      started = true
+      status = "session created"
+      print("[DRAMATIC_SHAPE] VR: " .. VRXR.status())
+    else
+      failed = VRXR.status()
+      print("[DRAMATIC_SHAPE] VR unavailable: " .. failed
+            .. " -- fix that, then toggle the VR row to retry")
+      return
+    end
+  end
+
+  if not VRXR.poll() then
+    -- the runtime took the session away (headset off, runtime shut down)
+    shutdown("session lost")
+    failed = "session lost -- toggle VR off and on to retry"
+    return
+  end
+  if not VRXR.isRunning() then return end
+
+  -- the headset paces the app now; vsync would fight it
+  if savedVsync == nil then
+    savedVsync = 1
+    pcall(function() savedVsync = love.window.getVSync() end)
+    pcall(love.window.setVSync, 0)
+  end
+
+  -- the battle camera holds still for as long as a headset is watching:
+  -- its drift is a flat screen's depth cue, and a swaying picture inside
+  -- VR reads as the world lurching
+  BattleCam.still = true
+
+  -- The battle snap's fade: while the camera the frame WANTS is not the
+  -- one it is showing, black rises; at full black the mount swaps; then
+  -- black lifts. Driven here, on game time, so a fight that ends during
+  -- the fade just turns it around.
+  local want = battleStage() and "battle" or "explore"
+  if want ~= camMode then
+    fadeAlpha = math.min(1, fadeAlpha + (dt or 0) / FADE_TIME)
+    if fadeAlpha >= 1 then camMode = want end
+  else
+    fadeAlpha = math.max(0, fadeAlpha - (dt or 0) / FADE_TIME)
+  end
+
+  local time, should = VRXR.waitFrame()
+  if not time then return end
+
+  -- the controllers, before the world renders: the frame the toggle
+  -- flips rungs on should be the frame that renders the new rig. The
+  -- state is kept in hand for renderWorld too -- the pokedex stands on
+  -- the same frame's left-hand pose.
+  local ctl = VRXR.input(time)
+  driveControls(ctl, dt, FirstPerson.engaged())
+
+  local worldUp = false
+  if should then
+    local views = VRXR.locateViews(time)
+    if views then
+      worldUp = renderWorld(views, ctl)
+    end
+  end
+  local quadPose = updateQuad(worldUp, FirstPerson.engaged())
+  VRXR.endFrame(time, worldUp or nil, quadPose)
+end
+
+-- ------- the window while a headset owns the picture
+
+-- The flat window becomes the mirror: the left eye, fitted to the window.
+-- Returns nil when there is nothing to mirror (the caller draws the flat
+-- path as ever).
+function VR.mirror(sw, sh)
+  if not (VR.active() and mirrorSrc) then return nil end
+  if not (mirrorCanvas and mirrorCanvas:getWidth() == sw
+          and mirrorCanvas:getHeight() == sh) then
+    local ok, c = pcall(love.graphics.newCanvas, sw, sh)
+    if not ok then return nil end
+    mirrorCanvas = c
+  end
+  local ok = pcall(function()
+    love.graphics.setCanvas(mirrorCanvas)
+    love.graphics.clear(0, 0, 0, 1)
+    local mw, mh = mirrorSrc:getDimensions()
+    local s = math.min(sw / mw, sh / mh)
+    love.graphics.setColor(1, 1, 1, 1)
+    love.graphics.draw(mirrorSrc, (sw - mw * s) / 2, (sh - mh * s) / 2, 0, s, s)
+    love.graphics.setCanvas()
+  end)
+  pcall(love.graphics.setCanvas)
+  return ok and mirrorCanvas or nil
+end
+
+-- window resize, hot reload: the eye canvases are Voxel3D's and go with
+-- its invalidate; ours is the mirror and the FBO ids learned from dead
+-- canvases
+function VR.invalidate()
+  if mirrorCanvas and mirrorCanvas.release then
+    pcall(mirrorCanvas.release, mirrorCanvas)
+  end
+  mirrorCanvas, mirrorSrc = nil, nil
+  if dexCanvas and dexCanvas.release then pcall(dexCanvas.release, dexCanvas) end
+  dexCanvas = nil
+  Pokedex.invalidate()
+  for k in pairs(fboCache) do fboCache[k] = nil end
+end
+
+return VR

lib/VRGL.lua

@@ -0,0 +1,237 @@
+-- VR: the raw OpenGL this mod is otherwise proud to never need.
+--
+-- OpenXR hands over its swapchain images as GL TEXTURE IDS, and LOVE never
+-- exposes the GL names behind its own canvases -- so getting a rendered
+-- eye from a love Canvas into a headset means dropping below LOVE for a
+-- few calls a frame: discover the canvas's framebuffer, blit it into the
+-- swapchain texture, and put the pipeline back exactly as LOVE believes it
+-- to be. Everything here is that, and only that.
+--
+-- Three rules keep this safe:
+--
+--   discovery over spelunking. The canvas's FBO id is read from the
+--   driver with documented queries (bind the canvas THROUGH LOVE, ask
+--   GL_DRAW_FRAMEBUFFER_BINDING) rather than from LOVE's internals, so a
+--   LOVE patch cannot move it out from under us.
+--
+--   restore what LOVE caches. LOVE tracks the bound framebuffer and skips
+--   redundant binds, so raw binds must end back at the exact binding LOVE
+--   thinks is current -- the default framebuffer, 0, since every call
+--   here runs between LOVE passes -- or LOVE's next draw lands in ours.
+--
+--   pcall at the rim, ffi inside. The FFI setup can fail (headless, a GL
+--   context without FBO entry points); it fails ONCE, at load(), and
+--   callers see `nil, reason` rather than an error mid-frame.
+
+local VRGL = {}
+
+local ffi = nil
+local gl = nil                -- opengl32 exports (GL 1.1 + wgl)
+local ext = {}                -- post-1.1 entry points via wglGetProcAddress
+local ready = false
+local reason = nil
+local fbo = nil               -- our scratch framebuffer, made once
+
+local GL = {
+  FRAMEBUFFER = 0x8D40,
+  READ_FRAMEBUFFER = 0x8CA8,
+  DRAW_FRAMEBUFFER = 0x8CA9,
+  DRAW_FRAMEBUFFER_BINDING = 0x8CA6,
+  COLOR_ATTACHMENT0 = 0x8CE0,
+  COLOR_BUFFER_BIT = 0x4000,
+  NEAREST = 0x2600,
+  LINEAR = 0x2601,
+  TEXTURE_2D = 0x0DE1,
+  FRONT = 0x0404,
+  BACK = 0x0405,
+}
+VRGL.GL = GL
+
+local CDEF = [[
+typedef void (__stdcall *PROC)();
+void* wglGetCurrentDC(void);
+void* wglGetCurrentContext(void);
+PROC wglGetProcAddress(const char*);
+unsigned int glGetError(void);
+void glGetIntegerv(unsigned int pname, int* params);
+void glReadBuffer(unsigned int mode);
+void glFlush(void);
+void glCopyTexSubImage2D(unsigned int target, int level, int xoffset,
+                         int yoffset, int x, int y, int width, int height);
+void glBindTexture(unsigned int target, unsigned int texture);
+typedef void (__stdcall *pfn_glBindFramebuffer)(unsigned int, unsigned int);
+typedef void (__stdcall *pfn_glGenFramebuffers)(int, unsigned int*);
+typedef void (__stdcall *pfn_glDeleteFramebuffers)(int, const unsigned int*);
+typedef void (__stdcall *pfn_glFramebufferTexture2D)(unsigned int,
+    unsigned int, unsigned int, unsigned int, int);
+typedef void (__stdcall *pfn_glBlitFramebuffer)(int, int, int, int,
+    int, int, int, int, unsigned int, unsigned int);
+]]
+
+-- One-time FFI setup. Idempotent, and every path out records why it
+-- stopped, so VR's status line can say something better than "no".
+function VRGL.load()
+  if ready then return true end
+  if reason then return false, reason end
+  local ok, err = pcall(function()
+    ffi = require("ffi")
+    -- cdef survives a reload; redefinition is the only error worth eating
+    pcall(ffi.cdef, CDEF)
+    gl = ffi.load("opengl32")
+    local function proc(name, typ)
+      local p = gl.wglGetProcAddress(name)
+      if p == nil then error(name .. " not exposed by this GL context", 0) end
+      return ffi.cast(typ, p)
+    end
+    ext.glBindFramebuffer = proc("glBindFramebuffer", "pfn_glBindFramebuffer")
+    ext.glGenFramebuffers = proc("glGenFramebuffers", "pfn_glGenFramebuffers")
+    ext.glDeleteFramebuffers =
+      proc("glDeleteFramebuffers", "pfn_glDeleteFramebuffers")
+    ext.glFramebufferTexture2D =
+      proc("glFramebufferTexture2D", "pfn_glFramebufferTexture2D")
+    ext.glBlitFramebuffer = proc("glBlitFramebuffer", "pfn_glBlitFramebuffer")
+  end)
+  if not ok then
+    reason = "GL interop unavailable: " .. tostring(err)
+    return false, reason
+  end
+  ready = true
+  return true
+end
+
+-- The window's device and GL contexts, which the OpenXR session binds to.
+function VRGL.contexts()
+  if not VRGL.load() then return nil, nil end
+  return gl.wglGetCurrentDC(), gl.wglGetCurrentContext()
+end
+
+-- The GL framebuffer behind a LOVE canvas. Bound through LOVE (so LOVE's
+-- own cache stays truthful), read from the driver, then released.
+function VRGL.canvasFBO(canvas)
+  if not VRGL.load() then return nil end
+  local id = nil
+  local ok = pcall(function()
+    love.graphics.setCanvas(canvas)
+    local out = ffi.new("int[1]")
+    gl.glGetIntegerv(GL.DRAW_FRAMEBUFFER_BINDING, out)
+    id = out[0]
+    love.graphics.setCanvas()
+  end)
+  pcall(love.graphics.setCanvas)
+  return ok and id or nil
+end
+
+-- Blit a LOVE canvas's pixels into a GL texture (an XR swapchain image),
+-- flipped vertically on the way: LOVE renders its canvases y-down, GL
+-- textures composite y-up, and the blit is the one place the two meet.
+--
+-- `srcFBO` comes from canvasFBO (cache it -- it is stable for the
+-- canvas's lifetime). Ends with framebuffer 0 bound, which is the binding
+-- LOVE believes in between its passes.
+function VRGL.blitToTexture(srcFBO, sw, sh, tex, tw, th)
+  if not ready then return false end
+  local ok = pcall(function()
+    if not fbo then
+      local out = ffi.new("unsigned int[1]")
+      ext.glGenFramebuffers(1, out)
+      fbo = out[0]
+    end
+    ext.glBindFramebuffer(GL.DRAW_FRAMEBUFFER, fbo)
+    ext.glFramebufferTexture2D(GL.DRAW_FRAMEBUFFER, GL.COLOR_ATTACHMENT0,
+                               GL.TEXTURE_2D, tex, 0)
+    ext.glBindFramebuffer(GL.READ_FRAMEBUFFER, srcFBO)
+    ext.glBlitFramebuffer(0, sh, sw, 0, 0, 0, tw, th,
+                          GL.COLOR_BUFFER_BIT, GL.LINEAR)
+    ext.glBindFramebuffer(GL.FRAMEBUFFER, 0)
+  end)
+  if not ok then pcall(function() ext.glBindFramebuffer(GL.FRAMEBUFFER, 0) end) end
+  return ok
+end
+
+-- Copy the WINDOW's currently displayed image (the front buffer -- the
+-- back buffer's contents are undefined after a swap) into a GL texture:
+-- the UI quad the headset floats in front of the world. Restores the read
+-- buffer to BACK, the default LOVE never changes.
+function VRGL.copyFrontBuffer(tex, w, h)
+  if not ready then return false end
+  local ok = pcall(function()
+    ext.glBindFramebuffer(GL.FRAMEBUFFER, 0)
+    gl.glReadBuffer(GL.FRONT)
+    gl.glBindTexture(GL.TEXTURE_2D, tex)
+    gl.glCopyTexSubImage2D(GL.TEXTURE_2D, 0, 0, 0, 0, 0, w, h)
+    gl.glBindTexture(GL.TEXTURE_2D, 0)
+    gl.glReadBuffer(GL.BACK)
+  end)
+  if not ok then pcall(function() gl.glReadBuffer(GL.BACK) end) end
+  return ok
+end
+
+-- Blit a REGION of the window's front buffer into a GL texture (an XR
+-- swapchain image), SCALED to (dw, dh) at the texture's origin. This is
+-- the panel's route: the whole-window copy above is pixel-for-pixel, so
+-- a window larger than the swapchain image simply ran off its edges --
+-- fullscreen cut the GB frame's own menu off the panel. A scaled blit
+-- has no such cliff: the letterbox region lands whole at the texture's
+-- own resolution whatever size the window is. Source coordinates are GL
+-- window space, origin bottom-left; LINEAR, because the region rarely
+-- matches the target size exactly and dropped rows read worse than a
+-- soft one. Restores the read buffer and framebuffer LOVE believes in.
+function VRGL.copyFrontRegionToTexture(tex, sx, sy, sw, sh, dw, dh)
+  if not ready then return false end
+  local ok = pcall(function()
+    if not fbo then
+      local out = ffi.new("unsigned int[1]")
+      ext.glGenFramebuffers(1, out)
+      fbo = out[0]
+    end
+    ext.glBindFramebuffer(GL.READ_FRAMEBUFFER, 0)
+    gl.glReadBuffer(GL.FRONT)
+    ext.glBindFramebuffer(GL.DRAW_FRAMEBUFFER, fbo)
+    ext.glFramebufferTexture2D(GL.DRAW_FRAMEBUFFER, GL.COLOR_ATTACHMENT0,
+                               GL.TEXTURE_2D, tex, 0)
+    ext.glBlitFramebuffer(sx, sy, sx + sw, sy + sh, 0, 0, dw, dh,
+                          GL.COLOR_BUFFER_BIT, GL.LINEAR)
+    ext.glBindFramebuffer(GL.FRAMEBUFFER, 0)
+    gl.glReadBuffer(GL.BACK)
+  end)
+  if not ok then
+    pcall(function()
+      ext.glBindFramebuffer(GL.FRAMEBUFFER, 0)
+      gl.glReadBuffer(GL.BACK)
+    end)
+  end
+  return ok
+end
+
+-- Copy the window's front buffer into a LOVE CANVAS (by its FBO id, from
+-- canvasFBO), flipped so the canvas reads top-down exactly like the
+-- window: what LOVE then draws from that canvas at (0,0) is the screen,
+-- row for row. The battle's VR quad is the caller: it needs the screen as
+-- something LOVE can CUT UP (scissored cutouts of the UI), not just as a
+-- finished texture -- copyFrontBuffer above is for the finished case.
+function VRGL.copyFrontToCanvas(dstFBO, w, h)
+  if not ready then return false end
+  local ok = pcall(function()
+    ext.glBindFramebuffer(GL.READ_FRAMEBUFFER, 0)
+    gl.glReadBuffer(GL.FRONT)
+    ext.glBindFramebuffer(GL.DRAW_FRAMEBUFFER, dstFBO)
+    ext.glBlitFramebuffer(0, 0, w, h, 0, h, w, 0,
+                          GL.COLOR_BUFFER_BIT, GL.NEAREST)
+    ext.glBindFramebuffer(GL.FRAMEBUFFER, 0)
+    gl.glReadBuffer(GL.BACK)
+  end)
+  if not ok then
+    pcall(function()
+      ext.glBindFramebuffer(GL.FRAMEBUFFER, 0)
+      gl.glReadBuffer(GL.BACK)
+    end)
+  end
+  return ok
+end
+
+function VRGL.status()
+  if ready then return "ok" end
+  return reason or "not loaded"
+end
+
+return VRGL

lib/VRRig.lua

@@ -0,0 +1,248 @@
+-- VR: the pose arithmetic -- how a headset eye becomes one of this mod's
+-- cameras. Pure math on purpose: no FFI, no OpenXR types, nothing a
+-- headless test cannot hold still. Everything device-shaped stays in
+-- VRXR/VRGL; everything world-shaped is here.
+--
+-- Two ways the world can sit around a headset, and they mirror the VOXEL
+-- ladder exactly:
+--
+--   DIORAMA   every orbit rung. The map is a tabletop miniature: a point
+--             of the world (the view centre) is pinned VIEW_DIST away
+--             along the rung's own viewing angle (dioramaAnchor), at the
+--             scale that reproduces the flat screen's framing
+--             (dioramaScale) -- so at rest the model presents exactly as
+--             the standard view does, and the head moves freely around it
+--             -- lean in and the town grows, walk around the table and
+--             see the far side of the buildings honest occlusion has been
+--             hiding.
+--
+--   FIRST_PERSON   the 1ST rung. The player's head is pinned to where the
+--             headset started, at FP_SCALE, so a 16-pixel person stands
+--             about 1.6 m tall and a cell is a stride. The HMD's own
+--             orientation becomes FirstPerson's yaw and pitch, so movement
+--             stays "push forward, go where you look" through the same
+--             FreeMove the flat screen uses.
+--
+-- SPACES AND UNITS. OpenXR LOCAL space is metres, +Y up, -Z the way the
+-- head faced at session start. World space is world PIXELS, +Y up, +Z
+-- south. The two are aligned axis-for-axis -- "away from you" is north --
+-- so the whole mapping is one translate-and-scale:
+--
+--   worldFromXr(p) = pivot + s * (p - anchor)
+--
+-- with `pivot` a world point, `anchor` the LOCAL-space point pinned to it,
+-- and `s` the scale in px/m. An eye's camera is then
+--
+--   worldFromEye = T(pivot) * S(s) * T(-anchor) * T(pose.pos) * R(pose.q)
+--   view         = the same chain inverted piece by rigid piece
+--
+-- and the VIEW deliberately ends in METRES: it un-scales the world, so eye
+-- space -- where the projection's near and far live -- is real-world
+-- metres whatever the mode's scale. Depth precision and clip planes stay
+-- sane at both 10 px/m and 128 px/m.
+
+-- the mod namespace (see main.lua): V.require loads a sibling module
+local V = ...
+
+local Mat4 = V.require("Mat4")
+
+local VRRig = {}
+
+-- first person's life size: 10 px/m makes a 16 px tile a 1.6 m stride
+VRRig.FP_SCALE = 10
+
+-- How far the diorama's pivot sits from the resting head, in metres --
+-- the arm's-length viewing distance the anchor and the scale below are
+-- both built around.
+VRRig.VIEW_DIST = 0.95
+
+-- Where, in LOCAL metres, the diorama's pivot sits: VIEW_DIST away along
+-- the RUNG'S OWN viewing angle. The flat screen's camera looks at the
+-- world `a` radians off vertical; putting the pivot at (-d cos a) below
+-- and (-d sin a) ahead of the resting head reproduces exactly that line
+-- of sight -- step onto the 35 rung and the table presents at 35 degrees,
+-- onto 75 and it rises toward eye level, easing between them as the rung
+-- tween runs. `heightOff` is the grab-drag adjustment, in metres of world
+-- travel (positive drags the world up).
+function VRRig.dioramaAnchor(angleRad, heightOff)
+  local d = VRRig.VIEW_DIST
+  return { 0,
+           -d * math.cos(angleRad or 0) + (heightOff or 0),
+           -d * math.sin(angleRad or 0) }
+end
+
+-- The diorama's scale, in world px per metre: the one that makes the
+-- table subtend the same field the flat screen frames. The flat camera
+-- fits `vh` world pixels in a lens of focal `focal` (Voxel.FOCAL); at
+-- VIEW_DIST the same framing needs vh * focal / d pixels to the metre --
+-- so the resting head sees the standard view's angle AND its apparent
+-- size, and the zoom rows (which change vh) keep working in VR.
+function VRRig.dioramaScale(vh, focal)
+  return math.max(16, (vh or 288) * (focal or 1) / VRRig.VIEW_DIST)
+end
+
+-- kept as the test suite's fixed example anchor, and as the fallback for
+-- an angle nobody supplied
+VRRig.TABLE = { 0, -0.45, -0.75 }
+
+-- ------- the battle mount
+--
+-- A staged fight snaps the headset to an OVER-THE-SHOULDER seat: the same
+-- line the flat battle camera stands on (eye through focus, so the player's
+-- mon is near-left and the foe far-right exactly as the flat shot frames
+-- them), but pulled in to BATTLE_DIST -- the flat rig is a long lens from
+-- fifteen metres back, and a headset's lens is its own eyes, so keeping the
+-- distance would shrink the fight to a stage seen from the back row. 66 px
+-- is the wide rig's own standing distance: six and a half metres at life
+-- scale, close enough to fill the view, far enough to hold both mons in it
+-- -- and short enough to stay inside the small rooms the wide rig exists
+-- for.
+VRRig.BATTLE_DIST = 66
+
+-- Where the head sits for a staged fight, and which way the mapping must
+-- turn so that seat FACES it. Returns the pivot (world px -- pin the XR
+-- origin here at FP_SCALE) and the yaw for eyeCamera: the flat camera
+-- looks along focus - eye, the resting headset looks along XR -Z (world
+-- north), and the yaw is what closes that gap.
+function VRRig.battleMount(eye, focus)
+  local dx = eye[1] - focus[1]
+  local dy = eye[2] - focus[2]
+  local dz = eye[3] - focus[3]
+  local len = math.sqrt(dx * dx + dy * dy + dz * dz)
+  if len < 1e-6 then return { eye[1], eye[2], eye[3] }, 0 end
+  local k = VRRig.BATTLE_DIST / len
+  -- Ry(yaw) sends XR forward (0,0,-1) to (-sin yaw, 0, -cos yaw); aiming
+  -- that along the horizontal of focus - eye solves to atan2 of eye - focus
+  return { focus[1] + dx * k, focus[2] + dy * k, focus[3] + dz * k },
+         math.atan2(dx, dz)
+end
+
+-- eye-space clip planes, in metres (see the unit note above)
+VRRig.NEAR = 0.05
+VRRig.FAR = 400
+
+-- ------- one eye's camera
+
+-- Build the placed-camera record for one eye.
+--
+--   pose    { pos = {x,y,z} metres, quat = {x,y,z,w} }  (OpenXR LOCAL)
+--   fov     { angleLeft, angleRight, angleUp, angleDown }  signed radians
+--   pivot   {x,y,z} world px pinned to `anchor`
+--   anchor  {x,y,z} LOCAL metres (VRRig.TABLE, or 0,0,0 for first person)
+--   scale   world px per metre
+--   yaw     optional turn of the whole mapping about +Y, radians: the
+--           battle mount faces the resting head at the arena with it.
+--           worldFromXr(p) becomes pivot + s * Ry(yaw) * (p - anchor).
+--
+-- Returns a table shaped for Voxel3D.camera: raw view + proj, the world
+-- eye and focus (for setLook, the water's lean, the sky), fov as a
+-- vertical span, and the curve declined -- a bent tabletop reads as a
+-- broken model, and first person already declines it on the flat screen.
+function VRRig.eyeCamera(pose, fov, pivot, anchor, scale, yaw)
+  local px, py, pz = pose.pos[1], pose.pos[2], pose.pos[3]
+  local q = pose.quat
+  local R = Mat4.fromQuat(q[1], q[2], q[3], q[4])
+
+  -- view = R^T * T(-pos) * T(anchor) * Ry(-yaw) * S(1/s) * T(-pivot)
+  local view = Mat4.mul(Mat4.transpose(R), Mat4.translate(-px, -py, -pz))
+  view = Mat4.mul(view, Mat4.translate(anchor[1], anchor[2], anchor[3]))
+  if yaw and yaw ~= 0 then
+    view = Mat4.mul(view, Mat4.rotateY(-yaw))
+  end
+  view = Mat4.mul(view, Mat4.scale(1 / scale, 1 / scale, 1 / scale))
+  view = Mat4.mul(view, Mat4.translate(-pivot[1], -pivot[2], -pivot[3]))
+
+  local proj = Mat4.fovProjection(fov.angleLeft, fov.angleRight,
+                                  fov.angleUp, fov.angleDown,
+                                  VRRig.NEAR, VRRig.FAR)
+
+  -- The eye's RAY FAN, in world axes: the direction a canvas point
+  -- (u, v in 0..1, left-to-right and top-to-bottom) looks along is
+  -- base + u * du + v * dv. The sky reads its per-pixel TRUE elevation
+  -- off this (a real skybox cannot be painted from any per-frame row
+  -- mapping -- that is exact only at the view's own azimuth and swims
+  -- everywhere else). Directions only, so the mapping's scale drops out;
+  -- the yaw must not (the battle mount and the snap turn swing the world).
+  local Rw = R
+  if yaw and yaw ~= 0 then Rw = Mat4.mul(Mat4.rotateY(yaw), R) end
+  local tl, tr = math.tan(fov.angleLeft), math.tan(fov.angleRight)
+  local tu, td = math.tan(fov.angleUp), math.tan(fov.angleDown)
+  -- world columns of the head's rotation: right (X), up (Y), forward (-Z)
+  local rxc, ryc, rzc = Rw[1], Rw[5], Rw[9]
+  local uxc, uyc, uzc = Rw[2], Rw[6], Rw[10]
+  local fxc, fyc, fzc = -Rw[3], -Rw[7], -Rw[11]
+  local skyRay = {
+    base = { fxc + rxc * tl + uxc * tu,
+             fyc + ryc * tl + uyc * tu,
+             fzc + rzc * tl + uzc * tu },
+    du = { rxc * (tr - tl), ryc * (tr - tl), rzc * (tr - tl) },
+    dv = { uxc * (td - tu), uyc * (td - tu), uzc * (td - tu) },
+  }
+
+  -- the eye and its forward, in world pixels: worldFromEye applied to the
+  -- origin and to -Z
+  local ax, ay, az = px - anchor[1], py - anchor[2], pz - anchor[3]
+  -- R's third column is the eye's +Z axis; forward is its negation
+  local fx, fy, fz = -R[3], -R[7], -R[11]
+  if yaw and yaw ~= 0 then
+    local c, s = math.cos(yaw), math.sin(yaw)
+    ax, az = c * ax + s * az, -s * ax + c * az
+    fx, fz = c * fx + s * fz, -s * fx + c * fz
+  end
+  local ex = pivot[1] + scale * ax
+  local ey = pivot[2] + scale * ay
+  local ez = pivot[3] + scale * az
+
+  return {
+    view = view,
+    proj = proj,
+    eye = { ex, ey, ez },
+    focus = { ex + fx * scale, ey + fy * scale, ez + fz * scale },
+    fov = fov.angleUp - fov.angleDown,
+    curve = 0,
+    skyRay = skyRay,
+  }
+end
+
+-- The WORLD model matrix a hand-held prop stands on: worldFromXr (the
+-- same mapping the eyes use -- so the prop is exactly where the hand is,
+-- whatever mode the mapping is in) composed with the hand's own tracked
+-- pose. A mesh authored in METRES rides it straight: the mapping's scale
+-- is what turns metres into world pixels, so the prop keeps its real
+-- size in the hand at the diorama's scale and at life scale alike.
+--
+--   model = T(pivot) * S(s) * Ry(yaw) * T(-anchor) * T(hand.pos) * R(hand.quat)
+function VRRig.propMatrix(pose, pivot, anchor, scale, yaw)
+  local m = Mat4.translate(pivot[1], pivot[2], pivot[3])
+  m = Mat4.mul(m, Mat4.scale(scale, scale, scale))
+  if yaw and yaw ~= 0 then m = Mat4.mul(m, Mat4.rotateY(yaw)) end
+  m = Mat4.mul(m, Mat4.translate(-anchor[1], -anchor[2], -anchor[3]))
+  m = Mat4.mul(m, Mat4.translate(pose.pos[1], pose.pos[2], pose.pos[3]))
+  local q = pose.quat
+  return Mat4.mul(m, Mat4.fromQuat(q[1], q[2], q[3], q[4]))
+end
+
+-- The flat compass numbers a head orientation implies, for driving
+-- FirstPerson (and through it FreeMove) from the HMD: yaw in this mod's
+-- convention (0 south, pi/2 east) and pitch positive-down.
+function VRRig.headYawPitch(quat)
+  local R = Mat4.fromQuat(quat[1], quat[2], quat[3], quat[4])
+  local fx, fy, fz = -R[3], -R[7], -R[11]
+  local flat = math.sqrt(fx * fx + fz * fz)
+  local yaw = flat > 1e-6 and math.atan2(fx, fz) or 0
+  local pitch = -math.asin(math.max(-1, math.min(1, fy)))
+  return yaw, pitch
+end
+
+-- The two pivots. First person pins the player's head; the diorama pins
+-- the view centre at the ground plane. `gh` is the ground height under
+-- the player (VoxelScene.groundAt), `eyeH` FirstPerson.EYE_HEIGHT.
+function VRRig.fpPivot(pxTopLeft, pyTopLeft, gh, eyeH)
+  return { pxTopLeft + 8, (gh or 0) + (eyeH or 13), pyTopLeft + 8 }
+end
+
+function VRRig.dioramaPivot(cx, cy)
+  return { cx, 0, cy }
+end
+
+return VRRig

lib/Voxel3D.lua

@@ -283,8 +283,66 @@ local activeShader = nil      -- the variant this pass bound
 -- resize, so the pair is stable for a session.
 local slots = {}
 local canvas, canvasW, canvasH = nil, 0, 0   -- the slot this pass bound
+local held = nil                             -- and the whole record for it
 local active = false
 
+-- A READABLE depth canvas, so a later pass in the same frame can ask the
+-- buffer questions rather than only write to it -- which is the whole of
+-- what makes screen-space reflections possible (see Water).
+--
+-- `depth = true` in the target list, which is what this used to bind,
+-- allocates an internal depth buffer that is written and tested and can
+-- never be sampled. An explicit canvas is the same buffer with a texture
+-- handle on it, and costs the same memory.
+--
+-- nil where the driver will not make one -- every depth format is optional
+-- in GLES and a canvas is the only honest test of any of them, so this asks
+-- for several in order of preference: 24 bits, the same 24 riding a stencil
+-- (a pairing some mobile drivers will texture when the bare format they
+-- refuse), 32-bit float, and 16 as the floor every GLES3 device can read.
+-- Refused all four, beginScene falls straight back to the internal buffer,
+-- which is exactly the old behaviour minus the reflections.
+local DEPTH_FORMATS = { "depth24", "depth24stencil8", "depth32f", "depth16" }
+
+local function newDepth(w, h)
+  if not (love.graphics and love.graphics.newCanvas) then return nil end
+  local c = nil
+  for _, format in ipairs(DEPTH_FORMATS) do
+    local ok, made = pcall(love.graphics.newCanvas, w, h,
+                           { format = format, readable = true })
+    if ok and made then c = made break end
+  end
+  if not c then return nil end
+  -- nearest: a depth is a distance, and a blend of two of them is a
+  -- distance to nothing. The march wants the texel it landed on.
+  pcall(c.setFilter, c, "nearest", "nearest")
+  pcall(c.setWrap, c, "clamp", "clamp")
+  -- and no compare mode: with one set, Texel returns a 0/1 shadow verdict
+  -- instead of the depth, which is not what any reader here wants
+  pcall(c.setDepthSampleMode, c)
+  return c
+end
+
+-- The bound target for the slot this pass holds: the colour canvas plus
+-- either the readable depth canvas or the internal buffer.
+local function depthTarget()
+  if held and held.depth then
+    return { held.canvas, depthstencil = held.depth }
+  end
+  return { canvas, depth = true }
+end
+
+-- Every GPU object one slot owns. The mirror is the copy of the frame the
+-- water pass reads (see beginWater); it is only ever made if something asks
+-- for one, so a session that never sees a lake never pays for it.
+local function releaseSlot(slotHeld)
+  for _, key in ipairs({ "canvas", "depth", "mirror" }) do
+    local obj = slotHeld[key]
+    if obj and obj.release then pcall(obj.release, obj) end
+    slotHeld[key] = nil
+  end
+end
+
 local IDENTITY = Mat4.identity()
 
 -- Whether the driver admits to supporting derivatives. Only a hint --
@@ -363,7 +421,14 @@ end
 -- ---------------------------------------------------------------- camera --
 
 -- An explicit camera, replacing the orbit below for as long as it is set:
--- { eye = {x,y,z}, focus = {x,y,z}, fov = radians, curve = k or nil }.
+-- { eye = {x,y,z}, focus = {x,y,z}, fov = radians, curve = k or nil,
+--   up = {x,y,z} or nil }.
+--
+-- A caller with matrices of its own -- the VR eyes, whose view comes from
+-- a tracked pose and whose projection is an off-centre frustum no
+-- eye/focus/fov triple can express -- sets `view` and `proj` instead, and
+-- the eye/focus fields stay for everything that reasons about the camera
+-- rather than projecting with it (setLook, the sky, the water's lean).
 --
 -- The orbit is the free-roam camera and it is described entirely by ONE
 -- number, the pitch, because that is all a camera following the player over
@@ -379,6 +444,48 @@ end
 -- way either way.
 Voxel3D.camera = nil
 
+-- This frame's camera RAY FAN, set by viewProjection alongside vp: the
+-- world direction a canvas point looks along (see Sky.paint's `ray`).
+-- Present for every free-pitch camera -- the VR eyes bring theirs
+-- (VRRig.eyeCamera), a placed eye/focus camera gets one built -- and nil
+-- for the orbit, whose frame-hung sky is the classic look.
+Voxel3D.skyRayLive = nil
+
+-- ------- which way, and how steeply, this camera looks
+--
+-- Two facts about the view direction, set alongside the eye and the focus
+-- because they ARE the eye and the focus, and read by anything that has to
+-- reason about the camera's ATTITUDE rather than about a point in front of
+-- it:
+--
+--   lookFlat   the view direction flattened onto the ground plane and
+--              normalized -- "the way the horizon lies from here", which is
+--              what a reflection leans toward at the steeper rungs (Water).
+--   descent    how far below horizontal the view runs, as a sine: 0 looking
+--              level, 1 looking straight down. It is the number that says
+--              whether there is a horizon in frame at all, and it answers
+--              the same way for the orbit and for a placed battle camera --
+--              which is why this is derived from the two vectors rather than
+--              read off Voxel.angle, a rung the battle camera does not have.
+--
+-- A camera looking exactly straight down has no horizontal direction at all,
+-- and lookFlat then keeps whatever it last held rather than becoming a zero
+-- vector nothing downstream could normalize.
+Voxel3D.lookFlat = { 0, 0, -1 }
+Voxel3D.descent = 0
+
+local function setLook(eye, focus)
+  local dx = focus[1] - eye[1]
+  local dy = focus[2] - eye[2]
+  local dz = focus[3] - eye[3]
+  local len = math.sqrt(dx * dx + dy * dy + dz * dz)
+  if len < 1e-6 then return end
+  Voxel3D.descent = math.max(0, math.min(1, -dy / len))
+  local flat = math.sqrt(dx * dx + dz * dz)
+  if flat < 1e-6 then return end
+  Voxel3D.lookFlat = { dx / flat, 0, dz / flat }
+end
+
 -- View and projection for a `vw` x `vh` world-pixel view centred on
 -- (cx, cy) in world pixels. Returns the combined matrix.
 function Voxel3D.viewProjection(cx, cy, vw, vh)
@@ -389,32 +496,84 @@ function Voxel3D.viewProjection(cx, cy, vw, vh)
     -- kept beside the eye for horizonY: where the sky's pale end goes is a
     -- question about which way this camera looks, and only these two answer it
     Voxel3D.focus = focus
+    setLook(eye, focus)
+    -- a camera that brought its own matrices (a VR eye) projects with
+    -- them; only the clip-space Y flip is added, for the same canvas
+    -- reason as every other branch here
+    if cam.view and cam.proj then
+      Voxel3D.fovY = cam.fov
+      -- the VR eyes bring their fan with them (VRRig.eyeCamera)
+      Voxel3D.skyRayLive = cam.skyRay
+      return Mat4.mul(Mat4.mul(Mat4.scale(1, -1, 1), cam.proj), cam.view)
+    end
     local dx = eye[1] - focus[1]
     local dy = eye[2] - focus[2]
     local dz = eye[3] - focus[3]
     local dist = math.max(1, math.sqrt(dx * dx + dy * dy + dz * dz))
+    -- kept for the passes that measure an ANGLE against this camera rather
+    -- than a position: the water's reflected sun is sized in radians, and
+    -- radians per canvas pixel is exactly this over the frame height
+    Voxel3D.fovY = cam.fov
     local proj = Mat4.perspective(cam.fov, vw / vh,
                                   math.max(1, dist * 0.05), dist * 4 + 4096)
     -- the same clip-space Y flip the orbit needs, for the same reason: we
     -- bypass LOVE's transform_projection and canvas coordinates run Y down
     proj = Mat4.mul(Mat4.scale(1, -1, 1), proj)
-    -- world up, so the horizon stays level -- a placed camera that rolled
-    -- with its own pitch would tip the whole arena
-    return Mat4.mul(proj, Mat4.lookAt(eye, focus, { 0, 1, 0 }))
+    -- The camera's RAY FAN, for the sky's skybox path (Sky.paint's `ray`):
+    -- a placed camera with a FREE PITCH -- the first-person rig, steered
+    -- by a mouse on the flat screen -- must not hang its gradient off the
+    -- frame, or looking up and down drags the bands with the view. Built
+    -- from the very basis the view below is: forward, the true right, the
+    -- true up, and the symmetric frustum's tangents.
+    local upv = cam.up or { 0, 1, 0 }
+    local fx, fy, fz = -dx / dist, -dy / dist, -dz / dist
+    local crx = fy * upv[3] - fz * upv[2]
+    local cry = fz * upv[1] - fx * upv[3]
+    local crz = fx * upv[2] - fy * upv[1]
+    local crl = math.sqrt(crx * crx + cry * cry + crz * crz)
+    if crl > 1e-6 then
+      crx, cry, crz = crx / crl, cry / crl, crz / crl
+      local cux = cry * fz - crz * fy
+      local cuy = crz * fx - crx * fz
+      local cuz = crx * fy - cry * fx
+      local tanY = math.tan(cam.fov / 2)
+      local tanX = tanY * (vw / vh)
+      Voxel3D.skyRayLive = {
+        base = { fx - crx * tanX + cux * tanY,
+                 fy - cry * tanX + cuy * tanY,
+                 fz - crz * tanX + cuz * tanY },
+        du = { crx * 2 * tanX, cry * 2 * tanX, crz * 2 * tanX },
+        dv = { cux * -2 * tanY, cuy * -2 * tanY, cuz * -2 * tanY },
+      }
+    else
+      Voxel3D.skyRayLive = nil
+    end
+    -- world up by default, so the horizon stays level -- a placed camera
+    -- that rolled with its own pitch would tip the whole arena. A caller
+    -- may hand its own up: the first-person BLEND does, because its far
+    -- end is the orbit, whose up leans with the pitch -- world up at the
+    -- orbit's steep end degenerates against a straight-down view.
+    return Mat4.mul(proj, Mat4.lookAt(eye, focus, cam.up or { 0, 1, 0 }))
   end
 
+  -- the orbit: a fixed pitch per rung, and the classic frame-hung sky --
+  -- no ray fan wanted
+  Voxel3D.skyRayLive = nil
+
   local a = Voxel.angle
   local focal = Voxel.FOCAL
   local dist = focal * vh
   -- the FOV that makes a straight-down camera at `dist` frame exactly `vh`
   -- world pixels, which is the framing the flat view already has
   local fov = 2 * math.atan(1 / (2 * focal))
+  Voxel3D.fovY = fov
 
   local focus = { cx, 0, cy }
   local eye = { cx, dist * math.cos(a), cy + dist * math.sin(a) }
   -- exposed for camera-facing billboards (VoxelScene yaws sprites at it)
   Voxel3D.eye = eye
   Voxel3D.focus = focus
+  setLook(eye, focus)
   -- perpendicular to the view direction in the YZ plane: north is screen-up
   -- when looking straight down, +Y is screen-up when looking level. Never
   -- parallel to the view direction, so there is no degenerate a = 0 case.
@@ -468,6 +627,56 @@ function Voxel3D.horizonY(h)
   return (y / w * 0.5 + 0.5) * h
 end
 
+-- The horizon as a LINE rather than a row, for a camera that can ROLL --
+-- a VR eye. A head tipped sideways tips the true horizon across the
+-- canvas, and a sky painted in flat rows then visibly hinges with the
+-- head. So: project the flat forward direction (a point ON the vanishing
+-- line) and the same direction nudged a hair of world-up (a point just
+-- above it); the difference is the canvas direction "down toward the
+-- ground", perpendicular to the horizon however the head is tipped.
+--
+-- Returns (ax, ay, edge, top): a unit axis in canvas pixels pointing from
+-- sky toward ground, the horizon's signed distance along it -- a pixel at
+-- canvas (x, y) is above the horizon while x*ax + y*ay < edge -- and,
+-- when `elev` (radians) is given, the distance the direction that far
+-- ABOVE the horizon projects to. `top` is what pins the gradient's far
+-- end to a real direction in the sky: extrapolating it linearly from a
+-- pixels-per-radian estimate left the bands sliding as a pitch moved the
+-- horizon through the frame, because a perspective's rows are tan-spaced,
+-- not angle-spaced. nil `top` (the elevated direction is outside this
+-- frustum's forward hemisphere) leaves the caller its estimate. nil
+-- everything with no horizon in front of this camera.
+function Voxel3D.horizonLine(w, h, elev)
+  local m, eye, focus = Voxel3D.vp, Voxel3D.eye, Voxel3D.focus
+  if not (m and eye and focus and w and h and h > 0) then return nil end
+  local dx = focus[1] - eye[1]
+  local dz = focus[3] - eye[3]
+  local len = math.sqrt(dx * dx + dz * dz)
+  if len < 1e-6 then return nil end
+  dx, dz = dx / len, dz / len
+  local function proj(vx, vy, vz)
+    local x = m[1] * vx + m[2] * vy + m[3] * vz
+    local y = m[5] * vx + m[6] * vy + m[7] * vz
+    local ww = m[13] * vx + m[14] * vy + m[15] * vz
+    if ww <= 1e-6 then return nil end
+    return (x / ww * 0.5 + 0.5) * w, (y / ww * 0.5 + 0.5) * h
+  end
+  local qx, qy = proj(dx, 0, dz)
+  if not qx then return nil end
+  local rx, ry = proj(dx, 0.02, dz)
+  if not rx then return nil end
+  local ax, ay = qx - rx, qy - ry
+  local al = math.sqrt(ax * ax + ay * ay)
+  if al < 1e-6 then ax, ay = 0, 1 else ax, ay = ax / al, ay / al end
+  local top = nil
+  if elev then
+    local ce, se = math.cos(elev), math.sin(elev)
+    local tx, ty = proj(dx * ce, se, dz * ce)
+    if tx then top = tx * ax + ty * ay end
+  end
+  return ax, ay, qx * ax + qy * ay, top
+end
+
 -- ------- the hour's light
 --
 -- What the scene shader multiplies every surface by (see dayTint in the
@@ -512,12 +721,83 @@ function Voxel3D.skyBody(w, h)
   return {
     x = (x / ww * 0.5 + 0.5) * w,
     y = (y / ww * 0.5 + 0.5) * h,
+    -- the body's WORLD direction, for the skybox path: a ray-fan caller
+    -- measures the twilight glow by the angle between a pixel's ray and
+    -- this, so the glow is pinned to the sky like the bands are (see
+    -- Sky.paint's glowDir)
+    dx = b.dx, dy = b.dy, dz = b.dz,
     moon = b.moon,
     glowAmt = amt,
     glowColor = color,
   }
 end
 
+-- ------- the VR sky's world-anchored pieces
+--
+-- Both exist because a headset showed the shortcuts: a gradient painted
+-- off the frame moved with the head that carried the frame, and a
+-- screen-space disc re-snapped its cell grid with every head movement
+-- and held its face square to the canvas instead of to the world. The
+-- gradient's fix rides the camera record itself (skyRay -- see VRRig and
+-- Sky's useRay path); the disc's is below.
+
+-- The sun or moon as a QUAD IN THE WORLD: the baked cell art
+-- (Sky.discImage) on a square spanned about the hour's direction, its
+-- corners projected through this very eye -- so the disc is pinned to
+-- the sky like the terrain is to the ground, stable under every head
+-- motion, its face upright over the world. Runs inside beginScene's sky
+-- window, before the depth mode is set, so the world draws over it.
+local discMesh = nil
+
+local function drawWorldDisc(w, h)
+  local b = DayNight.body()
+  if not (b and b.dy and b.dy > 0.005) then return end
+  local amt = DayNight.glow()
+  local img = Sky.discImage(b.moon, Sky.discLooming(amt, b.moon))
+  if not img then return end
+  local m = Voxel3D.vp
+  if not m then return end
+  local hl = math.sqrt(b.dx * b.dx + b.dz * b.dz)
+  if hl < 1e-6 then return end
+  -- right = horizontal, perpendicular to the direction; up completes it
+  local rx, rz = b.dz / hl, -b.dx / hl
+  local ux = -rz * b.dy
+  local uy = rz * b.dx - rx * b.dz
+  local uz = rx * b.dy
+  local ul = math.sqrt(ux * ux + uy * uy + uz * uz)
+  if ul < 1e-6 then return end
+  ux, uy, uz = ux / ul, uy / ul, uz / ul
+  if uy < 0 then ux, uy, uz = -ux, -uy, -uz end
+  -- apparent size is an ANGLE, the same fraction of the view the flat
+  -- screen's disc takes of its frame; the low sun looms exactly as there
+  local ang = Sky.DISC_FRAC * (Voxel3D.fovY or 1)
+  if Sky.discLooming(amt, b.moon) then ang = ang * 1.4 end
+  local k = math.tan(ang)
+  local verts = {}
+  local corners = { { -1, -1, 0, 1 }, { 1, -1, 1, 1 },
+                    { 1, 1, 1, 0 }, { -1, 1, 0, 0 } }
+  for i, c in ipairs(corners) do
+    local vx = b.dx + (rx * c[1] + ux * c[2]) * k
+    local vy = b.dy + (uy * c[2]) * k
+    local vz = b.dz + (rz * c[1] + uz * c[2]) * k
+    local x = m[1] * vx + m[2] * vy + m[3] * vz
+    local y = m[5] * vx + m[6] * vy + m[7] * vz
+    local ww = m[13] * vx + m[14] * vy + m[15] * vz
+    if ww <= 1e-6 then return end
+    verts[i] = { (x / ww * 0.5 + 0.5) * w, (y / ww * 0.5 + 0.5) * h,
+                 c[3], c[4] }
+  end
+  pcall(function()
+    if not discMesh then
+      discMesh = love.graphics.newMesh(4, "fan", "stream")
+    end
+    discMesh:setVertices(verts)
+    discMesh:setTexture(img)
+    love.graphics.setColor(1, 1, 1, 1)
+    love.graphics.draw(discMesh)
+  end)
+end
+
 -- ----------------------------------------------------------------- scene --
 
 -- Begin the 3D pass into a `w` x `h` pixel canvas centred on world
@@ -538,22 +818,29 @@ function Voxel3D.beginScene(w, h, cx, cy, vw, vh, sky, slot)
   end
   if not sh then return false end
   local name = slot or "world"
-  local held = slots[name]
-  if not (held and held.w == w and held.h == h) then
+  local slotHeld = slots[name]
+  if not (slotHeld and slotHeld.w == w and slotHeld.h == h) then
     local ok, c = pcall(love.graphics.newCanvas, w, h)
     if not ok then return false end
     c:setFilter("nearest", "nearest")
-    if held and held.canvas and held.canvas.release then
-      pcall(held.canvas.release, held.canvas)
-    end
-    held = { canvas = c, w = w, h = h }
-    slots[name] = held
+    if slotHeld then releaseSlot(slotHeld) end
+    -- the depth canvas is sized with its colour, so a window resize
+    -- reallocates the pair together and they can never disagree
+    slotHeld = { canvas = c, w = w, h = h, depth = newDepth(w, h) }
+    slots[name] = slotHeld
   end
+  held = slotHeld
   canvas, canvasW, canvasH = held.canvas, w, h
   -- a depth buffer is what makes occlusion real: walk behind a building and
   -- the building wins, with no y-sorting anywhere
-  local ok = pcall(love.graphics.setCanvas,
-                   { canvas, depth = true })
+  local ok = pcall(love.graphics.setCanvas, depthTarget())
+  if not ok and held.depth then
+    -- the readable canvas would not bind; fall back to the internal buffer
+    -- for the rest of this session rather than losing the whole 3D pass
+    pcall(held.depth.release, held.depth)
+    held.depth = nil
+    ok = pcall(love.graphics.setCanvas, depthTarget())
+  end
   if not ok then
     pcall(love.graphics.setCanvas)
     return false
@@ -561,6 +848,24 @@ function Voxel3D.beginScene(w, h, cx, cy, vw, vh, sky, slot)
   -- Ahead of the clear, because the sky's bands are placed off the ground
   -- plane's vanishing line and that is a property of this matrix.
   Voxel3D.vp = Voxel3D.viewProjection(cx, cy, vw, vh)
+  -- This frame's pixels per WORLD pixel: the size a diorama pixel is on
+  -- screen. The sky's dither grid is cut to it, and so is the water's --
+  -- one number, so the two break up on the same checkerboard.
+  Voxel3D.cell = w / math.max(1, vw or w)
+  -- A FREE-PITCH camera's sky is ANCHORED IN SPACE, where the orbit's is
+  -- glued to the frame. One discriminator: skyRayLive, set by
+  -- viewProjection above for every camera whose pitch the player steers
+  -- -- the VR eyes and the flat first-person rig alike. With a fan, the
+  -- gradient is a SKYBOX (every pixel takes its band, and its GBC
+  -- checker, from its ray's true elevation -- no motion of the camera
+  -- moves a band, only the clock recolours them) and the sun or moon
+  -- hangs in the WORLD (drawWorldDisc). Without one -- the orbit, whose
+  -- pitch is the rung's -- the classic frame-hung painting stands.
+  local skyRay = Voxel3D.skyRayLive
+  local hy = Voxel3D.horizonY(h)
+  -- where the sky's bottom edge lands, which is what the reflection
+  -- reads its bands against (see Water). nil when nothing painted bands.
+  Voxel3D.skyEdge = (sky and sky.bands) and Sky.region(h, hy) or nil
   if sky then
     love.graphics.clear(sky[1], sky[2], sky[3], sky[4] or 1, true, true)
     -- The sky goes down here, in the one window in this function where a
@@ -573,8 +878,14 @@ function Voxel3D.beginScene(w, h, cx, cy, vw, vh, sky, slot)
     -- are the same size as the world's own and follow every resize and zoom.
     -- The banded sky also hangs the hour's sun or moon (skyBody projects it
     -- through this very camera); a flat sky has no bands and hangs nothing.
-    Sky.paint(w, h, sky, Voxel3D.horizonY(h), w / math.max(1, vw or w),
-              sky.bands and Voxel3D.skyBody(w, h) or nil)
+    if skyRay and sky.bands then
+      Sky.paint(w, h, sky, nil, Voxel3D.cell, Voxel3D.skyBody(w, h),
+                nil, nil, skyRay)
+      drawWorldDisc(w, h)
+    else
+      Sky.paint(w, h, sky, hy, Voxel3D.cell,
+                sky.bands and Voxel3D.skyBody(w, h) or nil)
+    end
   else
     love.graphics.clear(0, 0, 0, 0, true, true)
   end
@@ -600,7 +911,7 @@ function Voxel3D.beginScene(w, h, cx, cy, vw, vh, sky, slot)
   pcall(sh.send, sh, "sunTexel", { texel, texel })
   if grid then
     pcall(sh.send, sh, "gridDark", VoxelGrid.DARK)
-    pcall(sh.send, sh, "gridWidth", VoxelGrid.WIDTH)
+    pcall(sh.send, sh, "gridWidth", VoxelGrid.width())
   end
   -- ordinary shading until the silhouette pass asks for otherwise. Sent
   -- every frame rather than once, because a scene that opened mid-ghost --
@@ -720,6 +1031,108 @@ function Voxel3D.flatten(color, amount)
   end
 end
 
+-- ------------------------------------------------------- the water pass --
+--
+-- A reflective surface has to READ the frame it is being drawn into: the
+-- colour of what is standing around it and the depth that says where. Both
+-- are attachments of the target this pass is bound to, and a texture cannot
+-- be sampled while it is one -- so for the length of the water draw the
+-- frame is taken apart:
+--
+--   the COLOUR is copied to a mirror canvas, which is a texture like any
+--   other and is what the reflection samples.
+--
+--   the DEPTH is simply detached. The water shader does the test itself
+--   against the texture (see Water), which is the same comparison the
+--   hardware would have made -- what it gives up is depth WRITES, and water
+--   is flat, never overlaps itself, and has nothing drawn under it later.
+--
+-- `paint`, when given, is called with the MIRROR bound and the scene shader
+-- set, to add things that must be REFLECTED without being composited yet.
+--
+-- The characters are the whole reason it exists. Gen 1 draws people over
+-- the world and water is world, so the cast has to composite AFTER the
+-- water -- but a reflection can only contain what was drawn BEFORE it, and
+-- a lake with everyone standing beside it and nobody in it reads as glass.
+-- Painting them into the mirror alone settles both: they are in the picture
+-- the water reflects and not yet in the picture the water is drawn into.
+--
+-- They go down depth-TESTED and depth-WRITE-FREE. Tested, so a figure behind
+-- a building is behind it in the reflection too; write-free because the very
+-- next thing to read that buffer is the water's own depth test, and a cast
+-- that had written to it would punch itself out of the water it is standing
+-- beside.
+--
+-- Returns the two textures, or nil when there is nothing to hand over: no
+-- readable depth canvas on this driver, or no pass open. A caller that gets
+-- nil draws its water like ordinary terrain, which is what this mode always
+-- did.
+--
+-- MUST be paired with endWater, which puts the frame back together.
+function Voxel3D.beginWater(paint)
+  if not (active and canvas and held and held.depth) then return nil end
+  if not held.mirror then
+    local ok, c = pcall(love.graphics.newCanvas, held.w, held.h)
+    if not (ok and c) then return nil end
+    pcall(c.setFilter, c, "nearest", "nearest")
+    pcall(c.setWrap, c, "clamp", "clamp")
+    held.mirror = c
+  end
+  love.graphics.setShader()
+  -- the frame's own depth rides along, so the paint below can test against
+  -- it; the copy underneath switches the test off rather than detaching it
+  local ok = pcall(love.graphics.setCanvas,
+                   { held.mirror, depthstencil = held.depth })
+  if not ok then
+    pcall(love.graphics.setCanvas, depthTarget())
+    return nil
+  end
+  love.graphics.setDepthMode("always", false)
+  -- COLOUR only. The last two arguments are what keep the depth buffer the
+  -- frame's rather than this canvas's: cleared here, the water's own depth
+  -- test a few lines later would find nothing in front of anything and every
+  -- lake would draw straight through the buildings standing in it.
+  love.graphics.clear(0, 0, 0, 0, false, false)
+  -- premultiplied over a cleared target is a straight copy: every channel
+  -- lands exactly as it stood, including the alpha, so the mirror is the
+  -- frame rather than the frame composited against something
+  love.graphics.setBlendMode("alpha", "premultiplied")
+  love.graphics.setColor(1, 1, 1, 1)
+  love.graphics.draw(canvas)
+  love.graphics.setBlendMode("alpha")
+  if paint and activeShader then
+    love.graphics.setDepthMode("lequal", false)
+    love.graphics.setShader(activeShader)
+    pcall(paint)
+    love.graphics.setShader()
+  end
+  love.graphics.setDepthMode()
+  -- and back to the scene canvas WITHOUT its depth: that texture is about
+  -- to be read
+  if not pcall(love.graphics.setCanvas, canvas) then
+    pcall(love.graphics.setCanvas, depthTarget())
+    return nil
+  end
+  return held.mirror, held.depth
+end
+
+-- Put the frame back: depth reattached, depth test and the scene shader as
+-- the pass had them. Safe to call after a beginWater that returned nil.
+function Voxel3D.endWater()
+  if not active then return end
+  pcall(love.graphics.setCanvas, depthTarget())
+  pcall(love.graphics.setDepthMode, "lequal", true)
+  love.graphics.setColor(1, 1, 1, 1)
+  if activeShader then love.graphics.setShader(activeShader) end
+end
+
+-- Whether a reflective water pass can run in this frame at all -- there is
+-- a depth texture to read. Callers use it to choose between the water
+-- shader and an ordinary terrain draw before they start moving canvases.
+function Voxel3D.depthReadable()
+  return (active and held and held.depth) and true or false
+end
+
 -- Whether what is drawn next carries the voxel wireframe. false for the
 -- length of a draw, true to put it back.
 --
@@ -931,18 +1344,28 @@ function Voxel3D.canvas()
   return canvas
 end
 
+-- The bound canvas's pixel size, for a pass that has to work in screen
+-- coordinates (the water's reflection marches in them).
+function Voxel3D.size()
+  return canvasW, canvasH
+end
+
 -- Drop the GPU objects (window resize, hot reload).
 function Voxel3D.invalidate()
-  for name, held in pairs(slots) do
-    if held.canvas and held.canvas.release then
-      pcall(held.canvas.release, held.canvas)
-    end
+  for name, slotHeld in pairs(slots) do
+    releaseSlot(slotHeld)
     slots[name] = nil
   end
   canvas, canvasW, canvasH = nil, 0, 0
+  held = nil
+  -- the VR sky's disc mesh belongs to this context like the canvases do
+  if discMesh and discMesh.release then pcall(discMesh.release, discMesh) end
+  discMesh = nil
   ShadowMap.invalidate()
   -- the sky is part of this pass and holds a shader of its own
   Sky.invalidate()
+  -- and so does the water, for the same reason
+  V.require("Water").invalidate()
   -- and the glass masks are textures of this context too
   GlassMask.invalidate()
 end

lib/VoxelGrid.lua

@@ -44,6 +44,19 @@ VoxelGrid.DARK = 0.45
 -- 1.0 here is the one-pixel wireframe.
 VoxelGrid.WIDTH = 1.0
 
+-- The same width in the CANVAS pixels the shader measures in, which is what
+-- every sender of it actually wants.
+--
+-- The two are the same number until AA renders the pass larger than the
+-- window (see AntiAlias): there a canvas pixel is a fraction of a display
+-- one, and a width left at 1.0 would come out a half or a quarter of a line
+-- after the fold -- the wireframe fading as the smoothing goes up, which
+-- reads as one row breaking the other. Scaled, it stays a one-pixel seam and
+-- simply gains the antialiasing everything else in the frame just gained.
+function VoxelGrid.width()
+  return VoxelGrid.WIDTH * V.require("AntiAlias").factor()
+end
+
 -- where it persists and the rows that cycle it (see ModSetting)
 VoxelGrid.setting = ModSetting.new(VoxelGrid.KEY, VoxelGrid.LABEL,
                                    { false, true }, { "OFF", "ON" })

lib/VoxelScene.lua

@@ -21,7 +21,12 @@ local TileShape = V.require("TileShape")
 local TerrainAtlas = V.require("TerrainAtlas")
 local Voxel = V.require("VoxelState")
 local Sky = V.require("Sky")
+local Water = V.require("Water")
+local VoxelGrid = V.require("VoxelGrid")
 local DayNight = V.require("DayNight")
+local FirstPerson = V.require("FirstPerson")
+local BattleBillboard = V.require("BattleBillboard")
+local Pokedex = V.require("Pokedex")
 local PaletteFX = require("src.render.PaletteFX")
 local Map = require("src.world.Map")
 
@@ -212,6 +217,22 @@ local function frameFor(def, facing, phase, flip)
   return frame, mirror
 end
 
+-- The facing a pose SHOWS this camera. The flat frames are "how this pose
+-- looks from the south", which is where the orbit always stands; a
+-- first-person eye stands anywhere, so deep enough into the blend the
+-- facing is remapped to how the pose looks from THERE -- walk behind an
+-- NPC and their card wears the back sprite. Used by the camera draw and
+-- the sun pass BOTH: the card the sun stored and the transform a lit card
+-- reads its own shadowing with must describe the same frame, or the
+-- mirror-flip half of the pair asks the map about texels the sun filed
+-- under the other cheek.
+local function viewFacing(p)
+  if FirstPerson.cardBlend() > 0.5 then
+    return FirstPerson.apparentFacing(p.facing, p.px + 8, p.py + 8)
+  end
+  return p.facing
+end
+
 -- FALLBACK ONLY (see castShadows below). Draw one entity's drop shadow as
 -- a decal: its current sprite frame as a single quad, flattened onto the
 -- ground along the sun line (Voxel3D.shadowMatrix). Runs inside
@@ -234,17 +255,40 @@ end
 -- Shared by the solid draw and the silhouette below, so the two can never
 -- drift apart -- a silhouette standing anywhere but exactly behind the
 -- figure would read as a second character.
+--
+-- IN FIRST PERSON the card stops leaning and starts TURNING: upright, yawed
+-- about its feet to face the eye (cylindrical billboarding). A south-facing
+-- card is invisible edge-on to an eye standing east of it, which no orbit
+-- camera could ever do and a first-person one does constantly. The blend
+-- carries one pose into the other -- the lean eases out as the yaw eases in
+-- -- and cardBlend is zero for every camera that is not the first-person
+-- rig, the battle's placed shot included, so nothing else moves.
+-- The pitch the sprite cards lean back by -- normally the rung's own
+-- camera angle, overridable in radians. VR sets the override to the top
+-- rung's 75 degrees for every diorama and battle frame: a table watched
+-- from a freely moving head has no one camera pitch for the cards to
+-- match, and the near-upright top-rung lean is the pose that reads as
+-- "standing" from anywhere around it. nil (the default, and the flat
+-- screen always) leans with the rung as ever.
+VoxelScene.spriteLean = nil
+
+local function leanAngle()
+  return VoxelScene.spriteLean or V.require("VoxelState").angle
+end
+
 local function billboardMatrix(px, py, y, mirror)
-  local Voxel = V.require("VoxelState")
-  local m = Mat4.mul(Mat4.translate(px + 8, y, py + 8),
-                     Mat4.rotateX(Voxel.angle - math.pi / 2))
+  local b = FirstPerson.cardBlend()
+  local m = Mat4.translate(px + 8, y, py + 8)
+  if b > 0 then
+    m = Mat4.mul(m, Mat4.rotateY(FirstPerson.cardYaw(px + 8, py + 8) * b))
+  end
+  m = Mat4.mul(m, Mat4.rotateX((leanAngle() - math.pi / 2) * (1 - b)))
   if mirror then m = Mat4.mul(m, Mat4.scale(-1, 1, 1)) end
   return Mat4.mul(m, Mat4.translate(-8, 0, 0))
 end
 
 local function billboardPull()
-  local Voxel = V.require("VoxelState")
-  return VoxelScene.pull(math.max(Voxel.angle, 0.05))
+  return VoxelScene.pull(math.max(leanAngle(), 0.05))
 end
 
 -- An authored FIGURE's card -- a person the tileset draws INTO a piece of
@@ -256,10 +300,23 @@ end
 -- the Pokemon Center couch reads face-on at every tilt like the NPCs
 -- around him. No cell centring: unlike a character he is not standing on a
 -- cell, he is standing where he was drawn, which may straddle two.
+--
+-- First person turns him at the eye like the walkers (see billboardMatrix)
+-- -- about his own middle, because unlike a character card his local space
+-- starts at x = 0 rather than being anchored by a -8 shift, and a yaw about
+-- his edge would swing him off his seat. The width rode in on the record
+-- for exactly this (ChunkMesher.buildFigureMeshes).
 local function figureMatrix(f, offX, offZ)
-  local Voxel = V.require("VoxelState")
-  return Mat4.mul(Mat4.translate(f.wx + (offX or 0), f.y, f.wz + (offZ or 0)),
-                  Mat4.rotateX(Voxel.angle - math.pi / 2))
+  local b = FirstPerson.cardBlend()
+  local wx, wz = f.wx + (offX or 0), f.wz + (offZ or 0)
+  local m = Mat4.translate(wx, f.y, wz)
+  if b > 0 and f.w and f.w > 0 then
+    local half = f.w / 2
+    m = Mat4.mul(m, Mat4.translate(half, 0, 0))
+    m = Mat4.mul(m, Mat4.rotateY(FirstPerson.cardYaw(wx + half, wz) * b))
+    m = Mat4.mul(m, Mat4.translate(-half, 0, 0))
+  end
+  return Mat4.mul(m, Mat4.rotateX((leanAngle() - math.pi / 2) * (1 - b)))
 end
 
 -- What the sun sees: the same card UNLEANED and flattened, exactly as
@@ -331,7 +388,7 @@ VoxelScene.drawEntity = drawEntity
 -- mesh for it.
 local function drawGhost(p)
   local def = p.sprite.def
-  local frame, mirror = frameFor(def, p.facing, p.phase, p.flip)
+  local frame, mirror = frameFor(def, viewFacing(p), p.phase, p.flip)
   local mesh = SpriteBillboards.shadowQuad(def, frame)
   if not mesh then return end
   local tex = p.sprite:resolveImage()
@@ -404,17 +461,25 @@ function VoxelScene.prefetch(state)
   -- crossing demotes the map just left, and it must not vanish from
   -- behind the player while its body variant builds; its ring is
   -- already masked out under this map's body, so the stand-in is safe.
-  local terrain = ChunkMesher.request(state.map, false, masks, true)
+  -- The water surface rides along with whichever variant answers: it was
+  -- cut out of that build's own geometry (ChunkMesher.pair), so the two
+  -- always come from the same slot and a lake is never drawn twice or left
+  -- as a hole.
+  ChunkMesher.request(state.map, false, masks, true)
+  local terrain, water = ChunkMesher.pair(state.map, false)
   if not terrain then
-    terrain = ChunkMesher.peek(state.map, true)
+    terrain, water = ChunkMesher.pair(state.map, true)
   end
-  local nbMesh = {}
+  local nbMesh, nbWater = {}, {}
   for i, nb in ipairs(state.neighbors or {}) do
-    nbMesh[i] = ChunkMesher.request(nb.map, true)
-                or ChunkMesher.peek(nb.map, false)
+    ChunkMesher.request(nb.map, true)
+    nbMesh[i], nbWater[i] = ChunkMesher.pair(nb.map, true)
+    if not nbMesh[i] then
+      nbMesh[i], nbWater[i] = ChunkMesher.pair(nb.map, false)
+    end
   end
   Voxel.ready = terrain ~= nil
-  return terrain, nbMesh
+  return terrain, nbMesh, water, nbWater
 end
 
 -- Capture every entity's pose for this frame. pose() advances the hop /
@@ -452,7 +517,13 @@ local function posesOf(state, spriteColors)
         gh = groundAt(state.map, e.cellX, e.cellY),
         lift = e.py - vy, colors = colors,
       }
-      if e == state.player then me = posed[#posed] end
+      if e == state.player then
+        me = posed[#posed]
+        -- marked so the camera draw can leave the card out in first
+        -- person, where it would fill the lens from inside; the SUN pass
+        -- reads the same list and deliberately does not check the mark
+        me.isPlayer = true
+      end
     end
   end
   return posed, me
@@ -490,6 +561,175 @@ end
 
 local glint = {}
 
+-- ------- the cast
+--
+-- Everybody standing on the map: the walkers, and the authored FIGURES the
+-- tileset draws into its own furniture (they ARE characters as far as the
+-- artwork is concerned, just ones drawn by the tileset instead of by a
+-- sprite sheet, so they get the same lean and the same camera-ward pull).
+--
+-- One function because it is drawn TWICE and the two must be identical: once
+-- into the frame, and once into the water's reflection copy (see drawWater --
+-- Gen 1 draws people over the world, and water is world, so the cast cannot
+-- be composited before the water it has to appear in).
+--
+-- Characters carry no wireframe out here, whatever the V-GRID row says. The
+-- seams are what makes the WORLD read as built out of voxels, and the people
+-- walking around in it are the one thing that should read as drawn instead --
+-- a grid over a 16x16 sprite lands a line every couple of display pixels and
+-- turns a face into a mesh. (The battle pass makes the opposite call for its
+-- own combatants, deliberately -- see BattleBillboard.)
+--
+-- Sprite sheets until the figure pass: their texture coordinates mean
+-- nothing to the tileset-shaped glass mask, so the glass is off or the
+-- panes' atlas positions stripe the cast with lamplight at night.
+local function drawCast(state, posed, atlasFor)
+  Voxel3D.glass(false)
+  Voxel3D.seams(false)
+  -- Characters, normally depth-tested: the camera-ward pull inside
+  -- drawEntity resolves the lean-over-the-wall-in-front case, and a
+  -- character genuinely behind a building is far deeper and loses the
+  -- test, so buildings and trees really occlude.
+  --
+  -- In first person two of them change: the player's own card is left out
+  -- (the eye is standing in it), and every other card wears the frame its
+  -- pose SHOWS this eye (viewFacing) rather than the one it shows the
+  -- south. Both run through here, so the water's reflection copy -- drawn
+  -- by this same function -- agrees with the frame to the pixel.
+  local hideMe = FirstPerson.hidePlayer()
+  for _, p in ipairs(posed) do
+    if not (p.isPlayer and hideMe) then
+      drawEntity(p.sprite, p.px, p.py, viewFacing(p), p.phase, p.flip, p.gh,
+                 p.colors, p.lift)
+    end
+  end
+  -- back on for everything textured from the atlas again -- figures, grass
+  -- and flowers all sample it, where the mask's coordinates are honest
+  Voxel3D.glass(true)
+  -- Figures after the walkers, so a player standing in front of the couch
+  -- wins the overlap -- the order the flat game draws them in.
+  local figPull = billboardPull()
+  eachFigure(state.map, 0, 0, function(mesh, model, caster)
+    Voxel3D.draw(mesh, atlasFor(state.map), model, figPull,
+                 ShadowMap.snug(caster))
+  end)
+  for _, nb in ipairs(state.neighbors or {}) do
+    eachFigure(nb.map, nb.ox, nb.oy, function(mesh, model, caster)
+      Voxel3D.draw(mesh, atlasFor(nb.map), model, figPull,
+                   ShadowMap.snug(caster))
+    end)
+  end
+  -- and the seams are back on for the terrain art that follows: grass and
+  -- flowers are the world's own drawing, not people
+  Voxel3D.seams(true)
+end
+
+-- ------- the water pass
+--
+-- Between the terrain and everything that stands on it, because water is a
+-- MIRROR and a mirror can only reflect what is already down: the ground, the
+-- shoreline, the trees and buildings behind it, and the sky the frame opened
+-- with.
+--
+-- THE CAST IS THE AWKWARD ONE, and it is settled by drawing it twice. Gen 1
+-- draws people over the world and water is world, so a surfing player has to
+-- composite OVER the water they are sitting on -- which puts them after it,
+-- and a reflection can only hold what came before it. So `cast` is painted
+-- into the reflection copy alone (Voxel3D.beginWater), where it is in the
+-- picture the water reflects and not yet in the picture the water is drawn
+-- into. Both draws go through drawCast, so they cannot come out different.
+--
+-- The ray march finds them the honest way round: a sprite is not in the
+-- DEPTH buffer at that point, so a ray aimed at one passes through to the
+-- terrain standing behind it and reads the copy there -- where the sprite is
+-- already painted. The reflection lands a hair off the sprite's own depth
+-- and exactly on its colour, which at a lake's worth of ripple is the same
+-- picture.
+--
+-- `draws` is a list of { mesh, texture, model }. Nothing is a special case:
+-- with the row OFF, no depth texture to read, or a shader that would not
+-- build, the same meshes go through the ordinary scene shader and come out
+-- as the flat animated water this mode always drew.
+-- The overworld's alone: the staged battle draws its water plain, always --
+-- its placed camera reads this pass wrong, and a stage set wants painted
+-- water anyway (see BattleScene, where the choice is argued).
+-- ------- and why the flat draw happens FIRST while the world is curved
+--
+-- The reflective pass writes no depth -- it cannot, the depth canvas is
+-- detached for the length of it so the shader can READ it -- and it does its
+-- own depth test against that texture instead. That test asks whether
+-- something opaque is in front, and it answers correctly for every case but
+-- one: WATER IN FRONT OF WATER. Nothing puts water in the depth buffer, so
+-- no lake can hide another, and the pass simply paints them in mesh order.
+--
+-- On a flat world that never matters: every surface lies in the one plane
+-- at its own recessed height, and a farther sheet always lands farther down
+-- the screen. THE WORLD CURVE ENDS THAT. The bend drops the world by the
+-- square of its distance, so the far side of the map swings down and back
+-- up into the near field of view -- and a sheet of sea a hundred and fifty
+-- tiles away, drawn later in the same mesh, paints straight over the pond
+-- at the player's feet. Not a reflection of the far shore: the far shore
+-- itself, rasterised on top of the water in front of you.
+--
+-- So WHILE THE CURVE IS ON, the meshes go down flat first, through the
+-- ordinary scene shader with depth writes on, and the reflective pass draws
+-- over the top of what survived: the depth buffer now holds the water
+-- surface, so the pass's own test throws the far sheet away, and the
+-- reflection COPY holds it too, so a ray grazing another part of the lake
+-- reads water rather than the void behind it.
+--
+-- With the curve OFF the prepass is not just unnecessary, it is a LIABILITY,
+-- and it stays off -- the reflective pass tests only against terrain, as it
+-- always did. Painting the surface into the depth texture turns the pass's
+-- test into a comparison of the surface against ITSELF, which asks the two
+-- rasterisations to agree to within interpolation error -- and on mobile
+-- GPUs they don't reliably (that fight is what put the Android port back on
+-- flat water). Confined to the curve there is no regression to reach: the
+-- flat world never had the far-shore bug in the first place.
+function VoxelScene.drawWater(draws, cast)
+  -- prepass only under the bend; see the header
+  local curved = (Voxel3D.curveK or 0) > 0
+  if curved then
+    for _, d in ipairs(draws) do
+      Voxel3D.draw(d[1], d[2], d[3])
+    end
+  end
+  local plain = not curved
+  if Water.enabled() and Voxel3D.depthReadable() then
+    local mirror, depth = Voxel3D.beginWater(cast)
+    local w, h = Voxel3D.size()
+    local ok = mirror and depth and Water.begin({
+      reflect = mirror, depth = depth,
+      vp = Voxel3D.vp, eye = Voxel3D.eye, curve = { Voxel3D.curveX or 0,
+                                                    Voxel3D.curveZ or 0,
+                                                    Voxel3D.curveK or 0 },
+      screen = { w, h }, cell = Voxel3D.cell, fov = Voxel3D.fovY,
+      skyEdge = Voxel3D.skyEdge, grid = VoxelGrid.enabled(),
+      lookFlat = Voxel3D.lookFlat, descent = Voxel3D.descent,
+    })
+    if ok then
+      for _, d in ipairs(draws) do
+        Water.draw(d[1], d[2], d[3])
+      end
+      Water.finish()
+      plain = false
+    end
+    -- Unconditionally, and OUTSIDE the success branch: beginWater unbinds
+    -- the shader and the depth mode BEFORE it can discover it cannot go on,
+    -- so a frame that bails halfway through has to be put back together
+    -- exactly like one that succeeded -- otherwise every pass after it runs
+    -- with no shader and no depth test.
+    Voxel3D.endWater()
+  end
+  -- the fallback flat draw -- unless the curve's prepass already put the
+  -- same meshes down, in which case a bailed frame is already whole
+  if plain then
+    for _, d in ipairs(draws) do
+      Voxel3D.draw(d[1], d[2], d[3])
+    end
+  end
+end
+
 -- A stamp of everything the sun pass depends on. Nothing in it moving
 -- means the shadow map it produced last frame is still exactly right, and
 -- redrawing the whole world from the sun would buy nothing -- which is
@@ -517,6 +757,10 @@ local function shadowSignature(terrain, nbMesh, posed, cx, cy, vw, vh)
   -- few times a minute rather than every frame.
   put(math.floor(ShadowMap.KX * 128))
   put(math.floor(ShadowMap.KZ * 128))
+  -- and the first-person head: the box is fitted around wherever it looks
+  -- and the sprite cards swap frames as it circles them, so a turn on the
+  -- spot re-fits and redraws exactly like a camera move ("" outside 1ST)
+  put(FirstPerson.signature())
   put(tostring(terrain))
   for i = 1, #nbMesh do put(tostring(nbMesh[i])) end
   for _, p in ipairs(posed) do
@@ -540,9 +784,12 @@ end
 -- left out on purpose: thousands of tufts would cast a speckle no bigger
 -- than the pixels it lands on, at the cost of the mesh being drawn twice.
 local function castShadows(state, terrain, nbMesh, posed, cx, cy, vw, vh,
-                           atlasFor)
+                           atlasFor, water, nbWater, battleCards, battleToken)
   if not ShadowMap.available() then return end
   local sig = shadowSignature(terrain, nbMesh, posed, cx, cy, vw, vh)
+  -- a staged fight's pics move every frame the animation does, and the sun
+  -- has to follow them (VR frames only; see render)
+  if battleToken then sig = sig .. "|btl" .. tostring(battleToken) end
   if not ShadowMap.stale(sig) then return end
   if not ShadowMap.begin(cx, cy, vw, vh) then return end
 
@@ -551,6 +798,15 @@ local function castShadows(state, terrain, nbMesh, posed, cx, cy, vw, vh,
     ShadowMap.draw(nbMesh[i], atlasFor(nb.map),
                    Mat4.translate(nb.ox, 0, nb.oy))
   end
+  -- The water surface, which the terrain mesh no longer carries (it is its
+  -- own reflective pass now -- see Water). The sun still has to see it, or
+  -- the map the light records has a hole at every lake and the frustum's
+  -- far plane answers for the surface a shoreline tree's shadow falls on.
+  ShadowMap.draw(water, atlasFor(state.map), nil)
+  for i, nb in ipairs(state.neighbors or {}) do
+    ShadowMap.draw(nbWater and nbWater[i], atlasFor(nb.map),
+                   Mat4.translate(nb.ox, 0, nb.oy))
+  end
   -- flower billboards live outside the terrain mesh (they draw after the
   -- characters, pulled -- see render), but the sun still sees them: a
   -- handful of cutouts per meadow, unlike the grass left out below.
@@ -563,6 +819,11 @@ local function castShadows(state, terrain, nbMesh, posed, cx, cy, vw, vh,
     ShadowMap.draw(ChunkMesher.flowers(nb.map), atlasFor(nb.map),
                    ShadowMap.snug(Mat4.translate(nb.ox, 0, nb.oy)))
   end
+  -- From here down it is the CAST, marked as such in the map (see
+  -- ShadowMap.sprites) so water can decline them: everything the world casts
+  -- still shades a lake, a silhouette of somebody standing beside it does
+  -- not. Ground, roofs and the characters themselves take them as before.
+  ShadowMap.sprites(true)
   -- authored figures cast too, for the same reason the flowers do: a
   -- handful of cards per map, and a person with no shadow reads as pasted on
   eachFigure(state.map, 0, 0, function(mesh, _, caster)
@@ -575,7 +836,12 @@ local function castShadows(state, terrain, nbMesh, posed, cx, cy, vw, vh,
   end
   for _, p in ipairs(posed) do
     local def = p.sprite.def
-    local frame, mirror = frameFor(def, p.facing, p.phase, p.flip)
+    -- viewFacing, exactly as the camera draw picks it (see viewFacing for
+    -- why the two passes must agree): in first person the sun's card
+    -- swaps frame as the eye circles, which costs a redraw the signature
+    -- already charges for (FirstPerson.signature) and keeps a card from
+    -- fringing against a mirror-flipped record of itself
+    local frame, mirror = frameFor(def, viewFacing(p), p.phase, p.flip)
     local mesh = SpriteBillboards.shadowQuad(def, frame)
     if mesh then
       ShadowMap.draw(mesh, p.sprite:resolveImage(),
@@ -584,16 +850,29 @@ local function castShadows(state, terrain, nbMesh, posed, cx, cy, vw, vh,
                                             mirror)))
     end
   end
+  -- a staged fight's mons (VR frames only): the same cards the eye pass
+  -- stands on the arena, snugged like every thin card, marked as the cast
+  -- so the water can decline them like everybody else's silhouette
+  for _, card in ipairs(battleCards or {}) do
+    ShadowMap.draw(BattleBillboard.mesh(), card.tex, ShadowMap.snug(card.model))
+  end
+  ShadowMap.sprites(false)
 
   ShadowMap.finish(sig)
 end
 
-function VoxelScene.render(state, w, h, vw, vh, paletteFor)
+-- Render the world. Without `eyes`, one frame into one canvas -- the flat
+-- path every rung has always taken. With `eyes` -- a list of
+-- { camera, w, h, slot, adopt } records, plus optional cx/cy for the
+-- scene centre -- the same frame is drawn once per entry and the list of
+-- canvases comes back: the VR path, two eyes over one shared shadow map,
+-- pose capture and glint step.
+function VoxelScene.render(state, w, h, vw, vh, paletteFor, eyes)
   -- With nothing cached at all (the first frame of a fresh toggle),
   -- return nil: the engine keeps the 2D path for the frame and
   -- Voxel.ready holds the camera tween at flat, so the switch waits
   -- invisibly instead of freezing or tilting an empty stage.
-  local terrain, nbMesh = VoxelScene.prefetch(state)
+  local terrain, nbMesh, water, nbWater = VoxelScene.prefetch(state)
   if not terrain then return nil end
 
   local cam = state.camera
@@ -630,12 +909,53 @@ function VoxelScene.render(state, w, h, vw, vh, paletteFor)
   end
 
   local posed, me = posesOf(state, spriteColors)
-  castShadows(state, terrain, nbMesh, posed, cx, cy, vw, vh, atlasFor)
 
-  if not Voxel3D.beginScene(w, h, cx, cy, vw, vh, skyFor(state.map)) then
-    return nil
+  -- The first-person rig, built (or blended) for this frame and handed to
+  -- Voxel3D BEFORE either pass runs: the sun's box is fitted around this
+  -- camera, and every card matrix asks it which way to turn. With the
+  -- blend fully out the call clears the placed camera and the orbit is
+  -- exactly what it always was. The scene centre it returns walks from
+  -- the orbit's view centre into the head, so the curve's focus and the
+  -- depth reference follow the camera actually in charge.
+  --
+  -- A VR frame skips all of it: the caller brought its own cameras, and
+  -- its own idea of the scene centre with them.
+  if not eyes then
+    local fpRig, fpCx, fpCy = FirstPerson.frame(me, cx, cy, vw, vh)
+    if fpRig then cx, cy = fpCx, fpCy end
+  elseif eyes.cx then
+    cx, cy = eyes.cx, eyes.cy
   end
 
+  -- A staged fight, seen by the VR eyes: the flat screen draws the battle
+  -- SCREEN while one is up (this pass never runs), but the headset keeps
+  -- looking at the world, so the world had better have the fight on it.
+  -- Fetched per frame for the sun, and again per EYE in drawScene, because
+  -- the cards yaw toward whichever eye is asking.
+  local battleCards, battleTex, battleToken = nil, nil, nil
+  if eyes then
+    local okB, cards, tex, token = pcall(function()
+      return V.require("OverworldBattle").worldCards()
+    end)
+    if okB and cards then
+      battleCards, battleTex, battleToken = cards, tex, token
+    end
+  end
+
+  -- The sun's box, pushed along the first-person look so it covers the
+  -- ground THIS camera sees (a no-op at blend zero): the orbit's fit
+  -- reaches far north and barely south, which is right for every rung
+  -- but a head free to face south.
+  local shCx, shCy = FirstPerson.shadowCenter(cx, cy, vh)
+  castShadows(state, terrain, nbMesh, posed, shCx, shCy, vw, vh, atlasFor,
+              water, nbWater, battleCards, battleToken)
+
+  -- Everything between beginScene and endScene, as one function: the flat
+  -- path runs it once, a VR frame runs it once PER EYE -- same posed
+  -- list, same shadow map, same glint, so the two eyes can never disagree
+  -- about anything but their viewpoint.
+  local function drawScene()
+
   Voxel3D.draw(terrain, atlasFor(state.map), nil)
   for i, nb in ipairs(state.neighbors or {}) do
     Voxel3D.draw(nbMesh[i], atlasFor(nb.map),
@@ -652,12 +972,40 @@ function VoxelScene.render(state, w, h, vw, vh, paletteFor)
   if not Voxel3D.shadowsActive() then
     Voxel3D.beginShadows()
     for _, p in ipairs(posed) do
-      drawShadow(p.sprite, p.px, p.py, p.facing, p.phase, p.flip, p.gh,
+      drawShadow(p.sprite, p.px, p.py, viewFacing(p), p.phase, p.flip, p.gh,
                  p.lift)
     end
     Voxel3D.endShadows()
   end
 
+  -- and the water over the top of it, reflecting everything just drawn plus
+  -- the sky the frame opened with (see drawWater).
+  --
+  -- After the fallback decals deliberately: those are the stand-in drop
+  -- shadows for a frame with no shadow map, they write no depth, and a
+  -- lake would otherwise wear one as a black smear. Water covers them,
+  -- which is the same answer the shadow map's own pass gives (see
+  -- ShadowMap.sprites) -- people do not shadow water either way.
+  local waterDraws = {}
+  if water then
+    waterDraws[#waterDraws + 1] = { water, atlasFor(state.map), nil }
+  end
+  for i, nb in ipairs(state.neighbors or {}) do
+    if nbWater and nbWater[i] then
+      waterDraws[#waterDraws + 1] = { nbWater[i], atlasFor(nb.map),
+                                      Mat4.translate(nb.ox, 0, nb.oy) }
+    end
+  end
+  -- the cast goes into the reflection copy only -- see drawWater for why it
+  -- cannot be composited yet and why it is drawn through the same function
+  -- the real pass below uses
+  if #waterDraws > 0 then
+    VoxelScene.drawWater(waterDraws, function()
+      drawCast(state, posed, atlasFor)
+    end)
+  end
+
+
   -- Sprite sheets from here to the figure pass: their texture coordinates
   -- mean nothing to the tileset-shaped glass mask, so the glass is off or
   -- the panes' atlas positions stripe the cast with lamplight at night
@@ -670,7 +1018,11 @@ function VoxelScene.render(state, w, h, vw, vh, paletteFor)
   -- wrote it, so the silhouette would paint over the player at all times.
   -- Every character then draws on top as usual, which leaves the silhouette
   -- showing in exactly one situation: where the world hides them.
-  if me then
+  --
+  -- Not in first person: the card it silhouettes is the one the camera is
+  -- standing inside, and "the world is in front of the player" is every
+  -- wall the player faces.
+  if me and not FirstPerson.hidePlayer() then
     Voxel3D.beginGhost()
     drawGhost(me)
     Voxel3D.endGhost()
@@ -689,41 +1041,55 @@ function VoxelScene.render(state, w, h, vw, vh, paletteFor)
   -- drawEntity resolves the lean-over-the-wall-in-front case, and a
   -- character genuinely behind a building is far deeper and loses the
   -- test, so buildings and trees really occlude.
-  Voxel3D.seams(false)
-  for _, p in ipairs(posed) do
-    drawEntity(p.sprite, p.px, p.py, p.facing, p.phase, p.flip, p.gh,
-               p.colors, p.lift)
-  end
-  -- back on for everything textured from the atlas again -- figures, grass
-  -- and flowers all sample it, where the mask's coordinates are honest
-  Voxel3D.glass(true)
-  -- Authored figures, alongside the characters and with the same lean and
-  -- the same camera-ward pull -- they ARE characters as far as the artwork
-  -- is concerned, just ones the tileset draws instead of a sprite sheet.
-  -- Drawn after the walkers so a player standing in front of the couch
-  -- wins the overlap, which is the order the flat game draws them in.
-  local figPull = billboardPull()
-  eachFigure(state.map, 0, 0, function(mesh, model, caster)
-    Voxel3D.draw(mesh, atlasFor(state.map), model, figPull,
-                 ShadowMap.snug(caster))
-  end)
-  for _, nb in ipairs(state.neighbors or {}) do
-    eachFigure(nb.map, nb.ox, nb.oy, function(mesh, model, caster)
-      Voxel3D.draw(mesh, atlasFor(nb.map), model, figPull,
-                   ShadowMap.snug(caster))
+  drawCast(state, posed, atlasFor)
+  -- The staged fight's mons, standing on their arena cells in THIS eye's
+  -- view (VR frames only; battleTex is nil otherwise). Rebuilt per eye
+  -- because the cards yaw toward the eye that is looking. No wireframe
+  -- and no glass on them for the reasons BattleBillboard and the battle
+  -- pass each argue: the cards are not on the voxel grid, and their
+  -- texcoords mean nothing to the tileset's pane mask. The hit flash
+  -- rides the same flatten the battle pass uses, held short of solid.
+  if battleTex then
+    local okB, cards = pcall(function()
+      return V.require("OverworldBattle").worldCards()
     end)
+    if okB and cards then
+      local BattleScene = V.require("BattleScene")
+      Voxel3D.glass(false)
+      Voxel3D.seams(false)
+      if battleTex.flash then
+        Voxel3D.flatten(BattleScene.FLASH_COLOR, BattleScene.FLASH_STRENGTH)
+      end
+      for _, card in ipairs(cards) do
+        Voxel3D.draw(BattleBillboard.mesh(), card.tex, card.model,
+                     BattleBillboard.PULL)
+      end
+      if battleTex.flash then Voxel3D.flatten(nil) end
+      -- and the MOVE ANIMATIONS, standing on the same arena: the
+      -- engine's own effects layer on the plane through both cells
+      -- (BattleScene.fxCard), pulled a little harder than the mons so
+      -- a burst plays over the card it is bursting on
+      local okA, fxTex, fxModel = pcall(function()
+        return V.require("OverworldBattle").worldAnim()
+      end)
+      if okA and fxTex and fxModel then
+        Voxel3D.draw(BattleBillboard.mesh(), fxTex, fxModel,
+                     BattleBillboard.PULL + 6)
+      end
+      Voxel3D.seams(true)
+      Voxel3D.glass(true)
+    end
   end
-  -- and the seams are back on for the terrain art that follows: grass and
-  -- flowers are the world's own drawing, not people
-  Voxel3D.seams(true)
   -- tall grass last, pulled camera-ward exactly as far as the characters
   -- were (same per-vertex shader bias, so grass never drifts either):
   -- relative depth between a walker and the tuft row south of their feet
   -- is preserved, so the row still overdraws feet -- the 3D version of
   -- the GB's grass-over-feet trick -- while grass keeps losing to the
   -- buildings it genuinely stands behind (far deeper than the pull).
-  local Voxel = V.require("VoxelState")
-  local pull = VoxelScene.pull(math.max(Voxel.angle, 0.05))
+  -- the same angle the cards leaned by (leanAngle honours VR's override),
+  -- so the tuft rows keep exactly the characters' own depth handicap
+  local lean = math.max(leanAngle(), 0.05)
+  local pull = VoxelScene.pull(lean)
   Voxel3D.draw(ChunkMesher.grass(state.map), atlasFor(state.map), nil, pull)
   for _, nb in ipairs(state.neighbors or {}) do
     Voxel3D.draw(ChunkMesher.grass(nb.map), atlasFor(nb.map),
@@ -739,7 +1105,7 @@ function VoxelScene.render(state, w, h, vw, vh, paletteFor)
   -- lands behind the card and the player obscures the patch they stand
   -- ON, while the nearest flower of the cell south (+20) stays in front
   -- and keeps overdrawing their feet.
-  local fpull = math.max(0, pull - 8 * math.sin(math.max(Voxel.angle, 0.05)))
+  local fpull = math.max(0, pull - 8 * math.sin(lean))
   -- flowers are snugged casters too, so they read their own shadowing
   -- through the same snugged transform the sun stored them with
   Voxel3D.draw(ChunkMesher.flowers(state.map), atlasFor(state.map), nil,
@@ -750,7 +1116,48 @@ function VoxelScene.render(state, w, h, vw, vh, paletteFor)
                  ShadowMap.snug(Mat4.translate(nb.ox, 0, nb.oy)))
   end
 
-  return Voxel3D.endScene()
+  -- The VR pokedex in the player's left hand, last of all: a prop over
+  -- the world drawn with real depth, so leaning it into a wall still
+  -- occludes honestly. Its frame only exists while a session is live and
+  -- the left hand is tracked (VR.lua sets it), so every flat frame skips
+  -- this in one field read. No wireframe and no glass, like the cast:
+  -- the device is a drawing riding the scene, not part of the terrain.
+  if Pokedex.frame then
+    Voxel3D.glass(false)
+    Voxel3D.seams(false)
+    Pokedex.draw()
+    Voxel3D.seams(true)
+    Voxel3D.glass(true)
+  end
+
+  end   -- drawScene
+
+  if not eyes then
+    if not Voxel3D.beginScene(w, h, cx, cy, vw, vh, skyFor(state.map)) then
+      return nil
+    end
+    drawScene()
+    return Voxel3D.endScene()
+  end
+
+  -- The VR frame: the same scene once per eye, each into its own named
+  -- canvas slot under its own placed camera. `adopt` hands the eye's
+  -- record to FirstPerson as the live rig, which is what turns the
+  -- billboards toward THIS eye in first person (cardBlend keys on rig
+  -- identity -- see FirstPerson) and leaves them leaning in the diorama,
+  -- where the blend is zero.
+  local out = {}
+  for i, eye in ipairs(eyes) do
+    Voxel3D.camera = eye.camera
+    if eye.adopt then FirstPerson.adoptVReye(eye.camera) end
+    if not Voxel3D.beginScene(eye.w, eye.h, cx, cy, vw, vh,
+                              skyFor(state.map), eye.slot) then
+      return nil
+    end
+    drawScene()
+    out[i] = Voxel3D.endScene()
+  end
+  return out
 end
 
 return VoxelScene

lib/VoxelState.lua

@@ -32,8 +32,18 @@ local Voxel = {}
 -- Its ANGLE is 35 degrees, the same as the rung of that name. The duplicate
 -- in the table is deliberate: the ladder is a list of what each rung LOOKS
 -- like, and two rungs may look the same while meaning different things.
-Voxel.ANGLES_DEG = { 0, 35, 15, 35, 50, 75 }
-Voxel.ANGLE_LABELS = { "OFF", "FULL", "15", "35", "50", "75" }
+--
+-- 1ST is the other rung that is more than an angle: the camera steps off its
+-- orbit entirely and stands in the player's own eyes (lib/FirstPerson.lua),
+-- with free look and free movement. Its ANGLE entry is 75 -- the orbit rung
+-- it hands over from -- because the tween in and out of first person starts
+-- from whatever the orbit shows, and the lowest rung is the one a dive into
+-- a head should start from. Everything angle-derived (the sky's fade, the
+-- billboard lean the blend eases away) reads that 75 while the first-person
+-- rig owns the actual camera.
+Voxel.ANGLES_DEG = { 0, 35, 15, 35, 50, 75, 75 }
+Voxel.ANGLE_LABELS = { "OFF", "FULL", "15", "35", "50", "75",
+                       "1ST (EXPERIMENTAL)" }
 Voxel.MAX_LEVEL = #Voxel.ANGLES_DEG - 1
 
 -- the rung FULL sits on, so nothing has to hunt for it by label
@@ -43,6 +53,13 @@ function Voxel.isFull(level)
   return (level or Voxel.level) == Voxel.FULL_LEVEL
 end
 
+-- the rung the first-person camera sits on, likewise
+Voxel.FP_LEVEL = 6
+
+function Voxel.isFirstPerson(level)
+  return (level or Voxel.level) == Voxel.FP_LEVEL
+end
+
 -- ------- what the hotkey walks
 --
 -- The ANGLE rungs only, with FULL left out. The key is a display-mode
@@ -51,7 +68,12 @@ end
 -- mid-walk, would silently turn the blur to maximum and flatten the horizon
 -- with no indication that a keypress had done so. FULL stays on the OPTIONS
 -- row, which is where a preset that changes other rows belongs.
-Voxel.HOTKEY_ORDER = { 0, 2, 3, 4, 5 }   -- OFF, 15, 35, 50, 75
+--
+-- 1ST is on the path: it changes the camera and only the camera, which is
+-- exactly what the key promises -- and the key is also the way back OUT of
+-- first person on a keyboard, where the mouse is captured and the OPTIONS
+-- menu is a trip.
+Voxel.HOTKEY_ORDER = { 0, 2, 3, 4, 5, 6 }   -- OFF, 15, 35, 50, 75, 1ST
 
 -- The rung a press moves to from `level`.
 --

main.lua

@@ -23,9 +23,16 @@
 -- the engine's TILT mode -- is engine plumbing driven by the records
 -- below.  This file declares; lib/ draws.
 --
--- Nothing here reaches collision, movement, triggers or scripts.  Voxel
--- mode is purely presentational: it changes what the world LOOKS like and
--- nothing about what it IS.
+-- Voxel mode is presentational: it changes what the world LOOKS like and
+-- nothing about what it IS.  ONE rung is the deliberate exception. 1ST --
+-- the first-person camera -- replaces the grid WALK with a free,
+-- camera-relative one while it is selected (lib/FreeMove.lua), because a
+-- head you can steer with a mouse demands feet that go where it looks.
+-- Even there the game is untouched: the walk asks the engine's own
+-- collision the same questions a grid step asks, keeps the player's
+-- logical cell synced, and fires the engine's own landing pipeline per
+-- cell crossed -- warps, encounters, ledges, gates and scripts all run
+-- exactly as themselves. Step off the rung and the grid walk is back.
 
 local mod = ...
 
@@ -80,6 +87,12 @@ local WorldCurve = V.require("WorldCurve")
 local OverworldBattle = V.require("OverworldBattle")
 local BattleExit = V.require("BattleExit")
 local DayNight = V.require("DayNight")
+local DayTint = V.require("DayTint")
+local Water = V.require("Water")
+local AntiAlias = V.require("AntiAlias")
+local FirstPerson = V.require("FirstPerson")
+local FreeMove = V.require("FreeMove")
+local VR = V.require("VR")
 
 -- Forward declaration: the voxel pipeline's update hook (registered below)
 -- calls this, and it is defined further down with the settings it drives.
@@ -159,6 +172,11 @@ mod.content.render_pipelines:register("voxel", {
     -- would fight anyone who changed one deliberately.
     applyFull(level)
     Voxel.update(dt, level)
+    -- the first-person head, on the same tick: its blend in and out of the
+    -- orbit, the mouse capture lifecycle, and the frame's stick-rate look.
+    -- Unconditional like Voxel.update, because the blend has to keep easing
+    -- OUT after the rung is left
+    FirstPerson.update(dt)
     -- the day/night clock, on the same always-running tick: Pipelines.update
     -- runs whatever the level, so time passes with the mode off, through
     -- battles and menus, and a CYCLE evening falls mid-fight exactly as it
@@ -183,6 +201,13 @@ mod.content.render_pipelines:register("voxel", {
     -- them announces it. Ahead of the active() gate, so switching it
     -- while voxel mode is OFF still invalidates what is cached.
     voidFill.check()
+    -- The whole VR frame -- session lifecycle, xrWaitFrame's pacing, both
+    -- eye renders, the layer submit -- rides this hook, because it is the
+    -- one tick that runs through menus, dialogs and battles, which is
+    -- what a headset needs the world (or at least the UI panel) to do.
+    -- Ahead of the active() gate: with the mode off, the headset still
+    -- shows the flat screen on the floating panel.
+    VR.update(dt)
     if not Voxel.active() then return end
     local Game = require("src.core.Game")
     local ow = Game and Game.overworld
@@ -194,6 +219,19 @@ mod.content.render_pipelines:register("voxel", {
   end,
 
   drawWorld = function(ctx)
+    -- the palette closure, stashed for the VR frame: it renders from the
+    -- update hook, where no ctx exists to carry one
+    VR.paletteFor = ctx.paletteFor
+    -- With a headset running, the window's world pass becomes the MIRROR
+    -- -- the left eye, fitted to the window -- rather than a third full
+    -- render of the scene. Everything else about the frame (the UI the
+    -- engine composites over this) is unchanged, which is exactly what
+    -- the headset's floating panel photographs.
+    if VR.active() then
+      local sw, sh = sceneSize(ctx)
+      local m = VR.mirror(sw, sh)
+      if m then return m end
+    end
     -- Terrain and characters are geometry; the field FX stay ordinary 2D
     -- draws composited on top, anchored through the same camera the 3D
     -- pass used (ctx.drawFx below).  The scene renders at the window's
@@ -201,21 +239,36 @@ mod.content.render_pipelines:register("voxel", {
     -- a magnified low-res image, while the FX closures keep drawing in
     -- world-pixel units.
     local sw, sh = sceneSize(ctx)
-    local canvas = VoxelScene.render(ctx.state, sw, sh,
+    -- With AA on, the whole pass runs into a canvas BIGGER than the window
+    -- and is folded back down at the end (see AntiAlias).  Nothing between
+    -- these two lines knows: every pass in the frame measures itself in the
+    -- canvas it was handed, so the sky's dither, the water's march and the
+    -- camera itself all come out the same picture at a higher sample rate.
+    local rw, rh = AntiAlias.expand(sw, sh)
+    local canvas = VoxelScene.render(ctx.state, rw, rh,
                                      ctx.vw, ctx.vh, ctx.paletteFor)
     if not canvas then return nil end   -- fall back to the 2D path
     if Voxel3D.beginOverlay() then
+      -- the FX closures are ordinary 2D draws sized in DISPLAY pixels, and
+      -- they are drawing into the supersampled canvas alongside everything
+      -- else -- so the scale goes up with it, or the "!" bubble lands the
+      -- right place at half the size.  project() already answers in canvas
+      -- pixels, so only the scale needs saying.
       ctx.drawFx(function(wx, wy) return Voxel3D.project(wx, 0, wy) end,
-                 ctx.scale)
+                 ctx.scale * AntiAlias.factor())
       Voxel3D.endOverlay()
     end
-    return canvas
+    -- and back to the window's own size, which is what the engine composites
+    -- one canvas pixel to one display pixel.  A pass-through when AA is off.
+    return AntiAlias.resolve(canvas, sw, sh, "world")
   end,
 
   invalidate = function()
     Voxel3D.invalidate()
     OverworldBattle.invalidate()
+    AntiAlias.invalidate()
     ChunkMesher.invalidate()   -- no map id = every cached mesh
+    VR.invalidate()            -- the mirror, and FBO ids of dead canvases
   end,
 })
 
@@ -281,13 +334,22 @@ applyFull = function(level)
   -- the horizon flat. The curve bends the world away from a walking player,
   -- which fights a fixed diorama framing
   WorldCurve.setting:setIndex(1, Game)
+  -- and the water reflecting everything it can: FULL is the diorama at its
+  -- most photographed, and a lake with the sky and the shoreline in it is
+  -- most of what makes the model read as being outdoors
+  Water.setting:setIndex(1, Game)
   -- and the view fitted to the window
   opts.zoom = 0
   Zoom.applyOptions(opts)
   -- battles on the map too: FULL means the whole mode, and a fight is where
-  -- half of it is spent. Set rather than forced -- the row is gone from the
-  -- menu while FULL is on, but a save that already had it off gets it on.
+  -- half of it is spent. Set and then LET GO of -- unlike the rows above, both
+  -- battle rows stay on the menu under FULL (see the rows hook), so this is
+  -- where the preset puts them and not where they are held.
   OverworldBattle.setting:setIndex(1, Game)
+  -- with both mons out there on it: BACK SPRITES keeps the player's own on the
+  -- menu, which is the one part of the old screen FULL is least about. Set the
+  -- same way, and changed back on the same row a keypress later.
+  OverworldBattle.backSetting:setIndex(1, Game)
   -- and the battle screen the staged fight is composed for. WIDE re-lays that
   -- screen out on a 304x144 surface, which moves every anchor the arena camera
   -- is solved against (OverworldBattle.forceOG); FULL has just switched staged
@@ -302,34 +364,97 @@ applyFull = function(level)
 end
 
 -- Whether a fight can be staged on the map, as far as the OPTIONS menu is
--- concerned: 3D-BTL is on, or FULL is selected -- which owns that row and
--- switches it on. Deliberately NOT gated on Voxel3D.available(): the engine
--- offers a pipeline's row whether or not the hardware can run it
--- (Pipelines.rows), so this mode's rows say ON on a machine without a depth
--- buffer too, and a menu that claims 3D battles are on must not also offer the
--- layout they cannot be drawn in.
+-- concerned: the 3D-BTL row, and nothing else.
+--
+-- It used to answer yes under FULL as well, on the grounds that FULL owned
+-- that row and switched it on. FULL no longer owns it -- the row stays on the
+-- menu under FULL and can be switched off there (see the rows hook) -- so that
+-- clause would now claim staged battles for a preset the player had just
+-- turned them off inside, pinning BATTLE LAYOUT to OG for a fight that is
+-- never staged. The row is the only thing that decides, which is what every
+-- other reader of this setting already believed: OverworldBattle.begin and
+-- wantsFront both gate on enabled() alone.
+--
+-- Deliberately NOT gated on Voxel3D.available(): the engine offers a
+-- pipeline's row whether or not the hardware can run it (Pipelines.rows), so
+-- this mode's rows say ON on a machine without a depth buffer too, and a menu
+-- that claims 3D battles are on must not also offer the layout they cannot be
+-- drawn in.
 local function stagedBattles()
-  local Pipelines = require("src.render.Pipelines")
-  return OverworldBattle.enabled() or Voxel.isFull(Pipelines.level("voxel"))
+  return OverworldBattle.enabled()
 end
 
 local SETTINGS = {
   { VoxelGrid.setting, "One-pixel wireframe along every voxel edge." },
   { WorldCurve.setting,
     "Bend the world down over the horizon, Animal Crossing style." },
+  { Water.setting,
+    "Reflections on water. FULL adds screen-space reflections of the "
+    .. "shoreline, the trees and the buildings behind it; SKY is the sky, "
+    .. "the sun and the moon alone, which is most of the look for a "
+    .. "fraction of the cost." },
+  -- `full` marks a row FULL does not take away. FULL owns the diorama's own
+  -- knobs; what a battle is drawn over, and how it is framed, are not that.
+  -- Off the OPTIONS menu while VR is on: the headset REQUIRES staged
+  -- battles (OverworldBattle.enabled answers true regardless of this row)
+  -- and forbids back sprites (backPinned answers false), so both rows
+  -- decide nothing there and a dead switch on the menu reads as broken.
   { OverworldBattle.setting,
     "Fight on the map: the battle draws over the nearest clear ground, "
-    .. "shot over the shoulder with a slow parallax drift." },
+    .. "shot over the shoulder with a slow parallax drift.",
+    when = function() return not VR.enabled() end, full = true },
+  -- Only offered while a fight can actually be staged on the map: with 3D-BTL
+  -- off the engine draws the classic screen, which is this row's ON already,
+  -- and a row that no longer decides anything is worse than no row.
+  { OverworldBattle.backSetting,
+    "Keep your own Pokemon on the battle menu, seen from behind in its "
+    .. "original slot, instead of standing it on the map facing the foe. "
+    .. "The foe is still out there on its own tile.",
+    when = function() return stagedBattles() and not VR.enabled() end,
+    full = true },
   { DayNight.setting,
     "What time it is outdoors: pin the sky to DAY, NIGHT, DUSK or DAWN, "
     .. "let CYCLE run it -- ten minutes of sun, ten of moon, with the "
     .. "shadows, the sky and the light following -- or SYNC it to the "
     .. "clock on the wall, so Kanto's evening falls when yours does." },
+  -- Marked `full` for the opposite reason the battle rows are: this is not a
+  -- knob on the look at all, it is what the look COSTS. FULL is a preset for
+  -- the diorama, not a licence to spend four times the fill rate on the
+  -- machine it happens to be running on, so it neither sets this nor takes
+  -- the row away -- the player decides what their hardware can carry, from
+  -- inside FULL like anywhere else.
+  { AntiAlias.setting,
+    "Smooth the stair-stepped edges of the 3D world -- roof ridges, ledge "
+    .. "lips, a tree against the sky -- by rendering the diorama larger than "
+    .. "the window and folding it back down. Every edge in the picture "
+    .. "softens with them, the tileset's own texels included, so the diorama "
+    .. "reads smoother rather than sharper. 2X costs half again as many "
+    .. "pixels in each direction and 4X twice, which makes this the most "
+    .. "expensive row in the mod.",
+    full = true },
+  -- `full` for the same reason as AA: not a knob on the look, a question
+  -- about the hardware on the desk.
+  { VR.setting,
+    "PCVR through OpenXR (SteamVR, Oculus, WMR). The diorama becomes a "
+    .. "tabletop model your head moves around; the 1ST rung stands you "
+    .. "inside the world at life size, looking where the headset looks. "
+    .. "Menus and dialogs float on a panel. Needs a Windows OpenXR runtime "
+    .. "and the mod running from a real folder; without them the row stays "
+    .. "and the game stays flat, with the reason on the console.",
+    -- on Windows the row stays even when a runtime is missing (the console
+    -- says why); off Windows -- mobile above all -- there is no VR to have
+    -- and the row does not exist
+    when = function() return VR.supported() end, full = true },
 }
 
 local schema = {}
-for i, entry in ipairs(SETTINGS) do
-  schema[i] = entry[1]:schema(entry[2])
+for _, entry in ipairs(SETTINGS) do
+  -- the VR row is absent from the mod manager's page too where the
+  -- platform cannot do VR at all -- the OPTIONS menu's `when` gates are
+  -- situational (a row hidden for now), this one is existential
+  if entry[1] ~= VR.setting or VR.supported() then
+    schema[#schema + 1] = entry[1]:schema(entry[2])
+  end
 end
 mod.options:define(schema)
 
@@ -340,6 +465,7 @@ mod.options:define(schema)
 --   6  T-SHIFT  cycle the blur ladder        (was 9)
 --   7  V-CURVE  cycle the horizon bend       (new)
 --   8  3D-BTL   toggle overworld battles     (new)
+--   9  WATER    cycle the water reflections  (new; 9 was T-SHIFT's old key)
 --
 -- Only 6 arrives by the documented route. Game:keypressed answers the
 -- engine's own display keys FIRST and returns -- 2 COLORS, 3 TILT, 4 ZOOM,
@@ -354,9 +480,12 @@ mod.options:define(schema)
 -- AND the engine's TILT on the same press.
 --
 -- Consequences worth being explicit about: while this mod is enabled, TILT
--- (3) and GBC FX (5) are unreachable by key. Both are still reachable on
--- the OPTIONS menu, and TILT is the one this mode supersedes anyway -- the
--- registry already forces it off whenever a world pipeline takes the pass.
+-- (3) and GBC FX (5) are unreachable by key -- and unreachable on the OPTIONS
+-- menu too, where both rows are taken away and both values held at zero (see
+-- pinEngineFx). Nothing is being hidden that still does something: TILT is the
+-- flat fake of what this mode does for real, the registry already forces it
+-- off whenever a world pipeline takes the pass, and GBC FX is a full-screen
+-- present pass over the top of the diorama. Uninstalling puts both back.
 --
 -- Everything the engine does around a pipeline hotkey has to happen here
 -- too, so the work is DELEGATED rather than reimplemented: Pipelines.hotkey
@@ -369,8 +498,37 @@ local HOTKEYS = {
   ["5"] = VoxelGrid.setting,
   ["7"] = WorldCurve.setting,
   ["8"] = OverworldBattle.setting,
+  ["9"] = Water.setting,
 }
 
+-- One step of the VOXEL angle ladder: everything a "3" press does, named
+-- so the pad's SELECT button (below) can make exactly the same step. The
+-- gate is the registry's own; the tilt/GBC FX clearing is the engine work
+-- the key has always delegated (see the wrap below for why).
+local function cycleVoxel(game)
+  local Pipelines = require("src.render.Pipelines")
+  local top = game.stack and game.stack:top()
+  if not Pipelines.canToggle("voxel", top, game.overworld) then return false end
+  Pipelines.setLevel("voxel", Voxel.nextHotkeyLevel(Pipelines.level("voxel")))
+  Pipelines.syncOptions(game.save.options)
+  -- 3 is the key that used to turn TILT on and sits next to the one that
+  -- used to turn GBC FX on, and this mod has taken both away. A player who
+  -- left either running before enabling the mod would otherwise have no
+  -- way back to off, and both fight the diorama -- so the VOXEL step
+  -- clears them on EVERY press, not just the press that switches on.
+  game.save.options.tilt = 0
+  game.save.options.gbcfx = 0
+  require("src.render.GBCFX").setLevel(0)
+  require("src.render.Tilt").setLevel(game.save.options.tilt or 0)
+  game:writeOptions()
+  return true
+end
+
+-- The VR stick click makes this same step (VR.stepView): the function is
+-- a local of this file, so the handoff is explicit rather than a
+-- reimplementation drifting out of date in lib/VR.lua.
+VR.cycleVoxel = cycleVoxel
+
 do
   local Game = require("src.core.Game")
   local Pipelines = require("src.render.Pipelines")
@@ -387,50 +545,30 @@ do
         -- 3 walks the ANGLE rungs and steps over FULL (Voxel.HOTKEY_ORDER),
         -- so the registry's plain "advance one and wrap" is not what it
         -- wants; 6 still is. The gate is the registry's own either way.
-        local stepped = false
+        -- The whole of 3's step lives in cycleVoxel, because the pad's
+        -- SELECT button makes the same step (see the handleInput wrap).
         if key == "3" then
-          if Pipelines.canToggle("voxel", top, self.overworld) then
-            Pipelines.setLevel("voxel",
-              Voxel.nextHotkeyLevel(Pipelines.level("voxel")))
-            stepped = true
-          end
-        else
-          stepped = Pipelines.hotkey(key, top, self.overworld) and true
-        end
-        if stepped then
+          if cycleVoxel(self) then return end
+        elseif Pipelines.hotkey(key, top, self.overworld) then
           Pipelines.syncOptions(self.save.options)
-          -- 3 is the key that used to turn TILT on and sits next to the one
-          -- that used to turn GBC FX on, and this mod has taken both away.
-          -- A player who left either running before enabling the mod would
-          -- otherwise have no way back to off, and both fight the diorama:
-          -- TILT is the flat fake of what this mode does for real, and GBC
-          -- FX is a full-screen present pass over the top of it. So the
-          -- VOXEL key clears them on EVERY press, not just the press that
-          -- switches the mode on -- cycling back round to OFF leaves them
-          -- off too, which is the state the key is now the only route to.
-          if key == "3" then
-            self.save.options.tilt = 0
-            self.save.options.gbcfx = 0
-            require("src.render.GBCFX").setLevel(0)
-          end
           require("src.render.Tilt").setLevel(self.save.options.tilt or 0)
           self:writeOptions()
           return
         end
       elseif Pipelines.canToggle("voxel", top, self.overworld) then
-        -- All three answer to the voxel pass's own free-roam gate --
+        -- All four answer to the voxel pass's own free-roam gate --
         -- borrowed from the registry rather than restated, so a press
         -- mid-warp or mid-cutscene is refused for the wireframe exactly when
-        -- it would be for the mode itself. Two of them parameterise that
-        -- pass; the third (3D-BTL) decides what a battle is drawn over, and
+        -- it would be for the mode itself. Three of them parameterise that
+        -- pass; the fourth (3D-BTL) decides what a battle is drawn over, and
         -- wants the same gate for a different reason: the answer is read
         -- when the fight starts, so flipping it from inside one would be a
         -- switch that appeared to do nothing.
         claim:cycle(self)
         -- 8 is one of the two ways staged battles get switched on, and they
-        -- pin BATTLE LAYOUT to OG (see the rows hook). The other two keys
+        -- pin BATTLE LAYOUT to OG (see the rows hook). The other keys
         -- parameterise the pass and leave the layout alone; the guard answers
-        -- for all three, so nothing here has to know which key it was.
+        -- for all of them, so nothing here has to know which key it was.
         if stagedBattles() then OverworldBattle.forceOG(self) end
         return
       end
@@ -464,10 +602,12 @@ local function insertGrouped(out, extra)
   return out
 end
 
--- FULL owns every one of those settings, so while it is selected they are
--- taken off the menu rather than left to be changed under it -- including
--- T-SHIFT, which is a pipeline row the engine put there. A row that no
--- longer decides anything is worse than no row.
+-- FULL owns the settings that describe the LOOK, so while it is selected those
+-- are taken off the menu rather than left to be changed under it -- including
+-- T-SHIFT, which is a pipeline row the engine put there. A row that no longer
+-- decides anything is worse than no row.
+--
+-- The battle rows are the exception and they stay; see the rows hook.
 local function dropRow(out, id)
   for i = #out, 1, -1 do
     if type(out[i]) == "table" and out[i].id == id then table.remove(out, i) end
@@ -475,12 +615,50 @@ local function dropRow(out, id)
   return out
 end
 
+-- ------- TILT and GBC FX are gone while this mod is installed
+--
+-- Both fight the diorama, and both were already half-taken: the mode's own key
+-- (3) forces them off on every press, and the registry switches TILT off
+-- whenever a world pipeline takes the pass. What was left was two rows the
+-- player could set and watch get reverted -- TILT is the flat fake of what
+-- this mode does for real, and GBC FX is a full-screen present pass over the
+-- top of the whole thing.
+--
+-- So they come OFF the menu, and are HELD at zero rather than merely dropped.
+-- Hiding a live setting is a trap: a save written before the mod was installed
+-- can carry TILT 3, and a row that is not there is a row that cannot turn it
+-- back off. Pinned wherever the value could have arrived from -- the menu
+-- opening, a save being loaded or begun -- so there is no route by which one
+-- of them is on and unreachable.
+--
+-- Everything they did is still reachable: uninstall the mod and both rows are
+-- back, at whatever they were last set to.
+local function pinEngineFx(game)
+  game = game or require("src.core.Game")
+  local opts = game and game.save and game.save.options
+  local Tilt = require("src.render.Tilt")
+  local GBCFX = require("src.render.GBCFX")
+  local changed = false
+  if opts then
+    changed = (opts.tilt or 0) ~= 0 or (opts.gbcfx or 0) ~= 0
+    opts.tilt, opts.gbcfx = 0, 0
+  end
+  pcall(Tilt.setLevel, 0)
+  pcall(GBCFX.setLevel, 0)
+  if changed and game.writeOptions then pcall(game.writeOptions, game) end
+end
+
 -- call next() first and decorate what comes back, so every other mod's
 -- rows survive this one
 mod.hooks:wrap("ui.options.rows", function(next, game, rows)
   local out = next(game, rows)
   if type(out) ~= "table" then return out end
   local Pipelines = require("src.render.Pipelines")
+  -- ahead of every branch below, including FULL's early return: these two are
+  -- off the menu whatever else this mod is or is not doing
+  pinEngineFx(game)
+  dropRow(out, "tilt")
+  dropRow(out, "gbcfx")
   -- BATTLE LAYOUT is the ENGINE's row, and this is the one place the mod takes
   -- one away. While a fight can be staged on the map, OG is the only layout it
   -- can be composed in (OverworldBattle.forceOG), so the value is pinned there
@@ -492,14 +670,32 @@ mod.hooks:wrap("ui.options.rows", function(next, game, rows)
     OverworldBattle.forceOG(game)
     dropRow(out, "battleLayout")
   end
-  if Voxel.isFull(Pipelines.level("voxel")) then
-    -- FULL keeps every mod row off the menu (the early return skips the
-    -- insert below), and holds DAYTIME at SYNC while the row is unreachable
+  local full = Voxel.isFull(Pipelines.level("voxel"))
+  if full then
+    -- FULL owns the rows that PARAMETERISE the diorama -- the wireframe, the
+    -- horizon bend, the blur, the hour -- so those come off the menu and
+    -- DAYTIME is held at SYNC while its row is unreachable.
     DayNight.forceSync(game)
-    return dropRow(out, "pipeline:tiltshift")
+    dropRow(out, "pipeline:tiltshift")
   end
   local extra = {}
-  for _, entry in ipairs(SETTINGS) do extra[#extra + 1] = entry[1]:row() end
+  for _, entry in ipairs(SETTINGS) do
+    -- Two things decide whether a row is offered.
+    --
+    -- FULL: a preset that owns the look, so the rows that describe the look go
+    -- with it. The BATTLE rows are not that -- 3D-BTL decides what a fight is
+    -- drawn OVER and BACK SPRITES how it is framed, and neither is a knob on
+    -- the diorama FULL is a preset for. FULL still SETS them on arrival (see
+    -- applyFull); it does not hold them, so leaving them on the menu is the
+    -- difference between a preset and a lock.
+    --
+    -- And a row whose own switch is off the table this frame (BACK SPRITES,
+    -- which needs a staged fight to be about) is left off with it. The mod
+    -- manager's page carries every one of them either way.
+    local offered = (entry.full or not full)
+                    and (not entry.when or entry.when())
+    if offered then extra[#extra + 1] = entry[1]:row() end
+  end
   return insertGrouped(out, extra)
 end)
 
@@ -629,12 +825,16 @@ do
     function OptionsMenu:update(dt)
       local before = Pipelines.level("voxel")
       local hadBattles = OverworldBattle.enabled()
+      -- the VR row hides the two battle rows while it is on, so stepping
+      -- it changes the LIST exactly the way 3D-BTL does
+      local hadVR = VR.enabled()
       local wasOn = idAt(self, self.index)
       inner(self, dt)
       local after = Pipelines.level("voxel")
       local crossedFull = after ~= before
                           and (Voxel.isFull(before) or Voxel.isFull(after))
-      if crossedFull or OverworldBattle.enabled() ~= hadBattles then
+      if crossedFull or OverworldBattle.enabled() ~= hadBattles
+         or VR.enabled() ~= hadVR then
         local rebuilt = OptionsMenu.new(self.game)
         self.rows = rebuilt.rows
         -- Follow the row the cursor was ON rather than the slot it was in:
@@ -660,6 +860,89 @@ end
 -- so this file keeps naming every engine seam the mod touches.
 OverworldBattle.install()
 
+-- ------- the first-person rung's inputs and its walk
+--
+-- 1ST needs two things no other rung does, and each is a named seam:
+--
+-- FirstPerson.install claims the LOOK inputs the engine ignores: the right
+-- stick's axes (Game:gamepadaxis passes them to Input, which returns early
+-- on anything but the left pair), relative mouse motion (love.mousemoved --
+-- there is no Game handler to wrap; the engine's own callback only feeds
+-- the mouse-as-touch debug path, which stays untouched), the mouse buttons
+-- while the cursor is captured (A and B -- there is no cursor to click UI
+-- with), and any touch that lands off the overlay's controls (a drag on
+-- open screen is the look; the d-pad and buttons still go to
+-- TouchControls, whose own d-pad finger is also read back analog as the
+-- move vector). Every wrap forwards whatever it does not claim, and claims
+-- only while 1ST is actually driving.
+--
+-- FreeMove.install wraps OverworldState:handleInput -- the one choke point
+-- where the grid walk reads the pad, and the same seam the engine's own
+-- Cycling Road pull lives behind. While 1ST drives, the walk is continuous
+-- and camera-relative; the player's logical cell stays synced and every
+-- per-cell consequence still runs through the engine's own machinery
+-- (onStepComplete, checkEdgeExit, checkLedgeHop, checkBoulderPush). The
+-- file argues the whole arrangement.
+FirstPerson.install()
+FreeMove.install()
+
+-- ------- SELECT walks the angle ladder
+--
+-- The same step the "3" key makes, on the pad's own button: a phone (and
+-- a controller) has no number row, and SELECT has no overworld job in
+-- Gen 1 -- its work is all in-menu, which this wrap never sees. The seam
+-- is OverworldState:handleInput, the same choke point the free walk
+-- replaced: every gate above it -- menus, dialogs, scripted moves,
+-- transitions -- already decided the overworld owns the buttons, so a
+-- SELECT here is free-roam by construction, exactly like the key. When
+-- the step is refused (mid-warp, no 3D pass) the press falls through to
+-- the engine's own handling, which is a no-op, as ever.
+--
+-- Installed AFTER FreeMove.install, deliberately: its wrap must sit
+-- OUTSIDE the free walk's, or first person -- where FreeMove.tick takes
+-- the frame and never calls further in -- would eat the button, and the
+-- one rung SELECT could not step off of would be 1ST itself.
+do
+  local OverworldState = require("src.world.OverworldController")
+  if not OverworldState.dramaticShapeSelectHook then
+    local inner = OverworldState.handleInput
+    function OverworldState:handleInput(...)
+      local Game = require("src.core.Game")
+      local input = Game.input
+      if input and input.wasPressed and input:wasPressed("select") then
+        if cycleVoxel(Game) then return end
+      end
+      return inner(self, ...)
+    end
+    OverworldState.dramaticShapeSelectHook = true
+  end
+end
+
+-- ------- edge-anchored menus stay in the GB frame while a headset is live
+--
+-- The engine's zoom-aware anchoring (Renderer:setUIAnchor) docks the START
+-- menu to the WINDOW's top-right edge. Both VR screens -- the floating
+-- panel and the Pokedex -- crop the window to the GB frame, so a menu at
+-- the window's edge is cropped away with the border it docked to. The
+-- engine's own answer to "a state composes its screen, keep every element
+-- inside it" is uiAnchorHold, computed per frame from this predicate; a
+-- live headset is exactly that situation for the WHOLE window, so the
+-- predicate answers yes for as long as one is. Held menus blit where they
+-- were drawn in the 160x144 canvas -- the START menu's 9,0 x 11 slot is
+-- already flush with the frame's right edge, which is the right edge of
+-- what the headset sees. Off-headset frames fall through untouched.
+do
+  local Game = require("src.core.Game")
+  if not Game.dramaticShapeAnchorHold then
+    local inner = Game.uiAnchorsHeldInStack
+    function Game.uiAnchorsHeldInStack(stack)
+      if VR.active() then return true end
+      return inner(stack)
+    end
+    Game.dramaticShapeAnchorHold = true
+  end
+end
+
 -- The overworld's own pushBattle is the choke point for a wild encounter or
 -- a trainer, and it is wrapped. A battle that arrives some other way -- a
 -- link battle, a script pushing a BattleState directly -- reaches this
@@ -714,6 +997,16 @@ mod.content.transitions:register(BattleExit.ID, {
 
 BattleExit.install()
 
+-- ------- and the hour on the flat world
+--
+-- The clock reaches the diorama through the voxel shader's own tint uniform,
+-- which the 2D tile path never runs -- so with the mode off, the same evening
+-- that fell on the diorama left the flat world at permanent noon. One clock,
+-- two worlds, one of them ignoring it. DayTint paints the same multiply over
+-- the composited flat world, between the world blit and the UI blit; the
+-- reasoning for that exact instant is in the file.
+DayTint.install()
+
 -- ------- what time it is
 --
 -- The cycle's clock rides the SAVE SLOT (save.modData, via mod.save): what
@@ -728,10 +1021,16 @@ end)
 
 mod.events:on("save.loaded", function()
   DayNight.restore()
+  -- a save written before this mod was installed can carry TILT or GBC FX
+  -- switched on, and their rows are not there to switch them back off (see
+  -- pinEngineFx). Answered here rather than only when the menu opens, so a
+  -- player who never opens it is not left playing under one.
+  pinEngineFx()
 end)
 
 mod.events:on("save.created", function()
   DayNight.restore()
+  pinEngineFx()
 end)
 
 -- The engine's own time-of-day seam. OverworldState:timeOfDay() is an
@@ -745,7 +1044,7 @@ mod.hooks:wrap("world.tod", function(next, tod, ctx)
   return DayNight.tod()
 end)
 
-mod.exports.version = "1.2.0"
+mod.exports.version = "1.5.2"
 -- exposed so a companion mod can pin its own tiles' shapes or read the
 -- camera without reaching into this mod's file layout
 mod.exports.lib = V

manifest.json

@@ -1,7 +1,7 @@
 {
   "id": "DRAMATIC_SHAPE",
   "name": "Dramatic Shape Voxel Mod",
-  "version": "1.2.0",
+  "version": "1.5.2",
   "api": 2,
   "entry": "main.lua",
   "profile": "content",
@@ -15,5 +15,6 @@
     "engine_internals"
   ],
   "affects_link": false,
-  "description": "A full 3D diorama overworld: extruded terrain, depth-buffered occlusion, voxel characters and a tilt-shift miniature pass -- and battles fought on the map itself, shot over the shoulder at the nearest clear ground with a slow parallax drift and a depth-of-field pass. Registers two render pipelines and claims hotkeys 3, 5, 6, 7 and 8 -- 3 and 5 displace the engine's TILT and GBC FX keys, both still reachable on the OPTIONS menu. Presentational only: it changes what a battle is drawn over, never where anybody stands."
+  "description": "A full 3D diorama overworld: extruded terrain, depth-buffered occlusion, voxel characters and a tilt-shift miniature pass -- and battles fought on the map itself, shot over the shoulder at the nearest clear ground with a slow parallax drift and a depth-of-field pass. Water reflects the sky, the sun, the moon and -- through a screen-space ray march -- the shoreline standing behind it. Registers two render pipelines and claims hotkeys 3, 5, 6, 7, 8 and 9 -- 3 and 5 displace the engine's TILT and GBC FX keys, both still reachable on the OPTIONS menu. Presentational only: it changes what a battle is drawn over, never where anybody stands.",
+  "github": "DramaticShape/DramaticShapeVoxelMod"
 }

mod.card

@@ -11,32 +11,53 @@ return {
       "with VOXEL on, the overworld draws as 3D geometry instead of flat tiles",
       "occlusion comes from a depth buffer rather than a y-sort, so buildings really hide what is behind them",
       "with 3D-BTL on, a battle draws over the map's nearest clear ground instead of over a white field",
+      "the battle's text box and menu are frosted glass over that ground rather than an opaque white slab, on the same panels the HUDs sit on",
       "the map's NPCs are culled for the length of a battle, so the wipe plays over an empty map",
       "a battle's letterbox voids go black rather than white, because the battle canvas is no longer white",
-      "VOXEL and the engine's TILT are mutually exclusive -- turning one on switches the other off",
-      "hotkeys 3 and 5 are taken over from the engine's TILT and GBC FX; both remain on the OPTIONS menu",
-      "the VOXEL key (3) turns TILT and GBC FX off on every press -- both fight the diorama, and 3 is now the only key that reaches either",
+      "the engine's TILT and GBC FX rows are taken OFF the OPTIONS menu and held at off for as long as this mod is installed -- TILT is the flat fake of what this mode does for real, GBC FX is a full-screen pass over the top of it; uninstalling puts both rows back",
+      "hotkeys 3 and 5 are taken over from those two, which have no key and no row while this is loaded",
+      "SELECT in free roam steps the VOXEL ladder exactly as hotkey 3 does -- the button has no overworld job in Gen 1, and phones and pads have no number row; menus keep it untouched",
+      "on the 1ST rung ONLY, the grid walk is replaced by free camera-relative movement: collision, warps, ledges, encounters and scripts still run through the engine's own machinery, and every other rung leaves movement untouched",
+      "on the 1ST rung the mouse cursor is captured for free look; left click is A, right click is B, and any touch off the overlay's controls drags the view",
     },
     added = {
-      "VOXEL options row and hotkey 3 (OFF / 15 / 35 / 50 / 75 degrees)",
+      "VOXEL options row and hotkey 3 (OFF / 15 / 35 / 50 / 75 degrees / 1ST, a first-person camera with free look and free movement)",
       "T-SHIFT options row and hotkey 6 (OFF / 1 / 2 / 3), the miniature blur",
       "V-GRID on hotkey 5 and V-CURVE on hotkey 7",
+      "WATER on hotkey 9 (FULL / SKY / OFF, FULL by default): the water surface becomes a field of pixel-tall voxel columns rising and falling as waves, reflecting the sky, the sun, the moon and the cast standing beside it -- and, on FULL, the shoreline, trees and buildings behind it, by a screen-space ray march",
       "3D-BTL on hotkey 8 (ON / OFF, on by default), battles fought on the world map",
+      "BACK SPRITES options row (OFF / ON, off by default), which keeps your own Pokemon on the battle menu in its classic slot while the foe stands out on the map",
+      "VR options row (OFF / ON, off by default): PCVR through OpenXR on Windows -- the diorama as a head-tracked tabletop model presented at the rung's own angle and framing on the orbit rungs, life-size first person on 1ST, a staged battle snapping the headset (through a fade to black) into the flat game's own over-the-shoulder seat at life scale, a voxel Pokedex flush along the left controller in first person and in battles (menus, dialogs and the 2D battle screen on its screen; the diorama does without it), the sky and its sun and moon anchored in space (bands, GBC dither and twilight glow alike -- nothing in the sky reacts to the head), the floating panel wearing the GB frame near-square rather than the whole monitor-wide window (scaled into the headset, so the picture and its ratio are identical at every window size, fullscreen included), the window as mirror; needs a runtime (SteamVR/Oculus/WMR) and the mod on a real folder",
+      "VR controllers (Touch/Index/WMR, rebindable in the runtime): left stick moves, A/B are A/B, either trigger is START, left stick click steps the VOXEL angle ladder exactly as the 3 key and SELECT do; in 1ST the right stick snap-turns 45 degrees a flick; in the diorama the right stick zooms and a squeezed grip drags the table's height; no controller button leaves VR -- that is the VR row's job",
+      "a day/night clock that reaches the flat 2D overworld as well as the diorama -- outdoor maps only, and only when the hour is not midday",
       "an over-the-shoulder battle camera on a slow parallax orbit, with a depth-of-field pass that holds both mons sharp",
       "a sky behind the diorama at the 75-degree rung, outdoor maps only, coloured by the active palette mode",
       "a hand-authored tile shape profile (data/voxel_heights.lua) a mod can extend",
     },
     known = {
       "needs shader and depth-canvas support; without them the rows still cycle but the world stays 2D and battles draw plainly",
+      "water reflections additionally need a READABLE depth canvas; a driver without one draws the flat animated water this mode always drew",
+      "WATER on FULL ray-marches the depth buffer per water pixel, so a map that is mostly sea costs real fill rate on a weak GPU -- SKY is the same look minus the ray march, and OFF is the flat water",
+      "a screen-space reflection can only reflect what is in the frame: a tree just off the top edge is not in the water below it, and a ray that runs off the side fades into the sky rather than ending on a line",
       "a map with no 3x6 clearing falls back to a 1x4 one, and a map with neither draws the plain battle screen",
       "the arena is where the CAMERA goes -- nobody is moved, so a fight staged across the map is a shot of that ground, not a trip to it",
       "the battle backdrop renders at the GB's 160x144 to match the pics composited over it, so it is chunkier than the free-roam pass",
       "menus and cutscenes are unaffected -- outside a battle the mode only draws the free-roam overworld",
       "terrain meshes are cached per map, so the first frame after entering a large map costs a build",
+      "1ST needs the 3D pass like every rung; without it the level still persists but the world stays 2D and the grid walk stays in charge",
+      "in 1ST, scripted walks, ledge hops and spinner slides play out as the grid moves they are, with the camera riding along; free control resumes when they land",
+      "rooms have no ceilings, so a first-person look over an interior wall shows the void the diorama always had behind it",
+      "VR is Windows x64 only (the shipped loader and the Win32 GL binding): on any other platform -- mobile above all -- the VR row is absent from the OPTIONS menu and the manager's page both, and a stored vr=true carried over in a save is ignored. On Windows it renders the scene once per eye (heavy with WATER FULL or AA up); pad/keyboard/mouse keep working alongside the XR controllers. The loader DLL is found wherever the mod was put -- the dev tree, an installed release's save directory, or an imported archive, from which it is copied once into the save directory so the FFI has a real disk path",
+      "VR on and off are both the VR row's job (options menu or manager); no controller button does either",
+      "the Pokedex needs a TRACKED left controller; without one there is no device in hand and the floating panel carries the UI as before",
+      "while the VR row is ON, 3D-BTL is held ON and BACK SPRITES held OFF (the headset's battle staging assumes both), and both rows leave the OPTIONS menu until VR goes off -- their stored values come back with them",
+      "while a headset is live the battle HUDs keep their classic in-frame slots instead of snapping to the window's edges, and the engine's edge-anchored menus (the START menu above all) are held inside the frame the same way, on the flat mirror too -- both VR screens crop to the GB frame, and a block at the window's edge would be cropped away with it",
+      "VR swapchains prefer plain RGBA8; a runtime that only offers sRGB shows slightly lifted colours",
     },
   },
   credits = {
     { who = "pret/pokered", for_ = "the tile and sprite data the geometry is derived from" },
+    { who = "The Khronos Group", for_ = "the OpenXR loader shipped unmodified in assets/vr (Apache-2.0; full license text alongside the DLL)" },
   },
   compat = { engine = ">=0.1.37 <2.0.0", modApi = 2 },
 }

oxr/OpenXR.Loader.nuspec

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<package xmlns="http://schemas.microsoft.com/packaging/2013/05/nuspec.xsd">
+  <metadata>
+    <id>OpenXR.Loader</id>
+    <version>1.0.10.2</version>
+    <authors>Khronos Group</authors>
+    <owners>Khronos Group</owners>
+    <requireLicenseAcceptance>false</requireLicenseAcceptance>
+    <license type="expression">Apache-2.0</license>
+    <licenseUrl>https://licenses.nuget.org/Apache-2.0</licenseUrl>
+    <projectUrl>https://github.com/KhronosGroup/OpenXR-SDK</projectUrl>
+    <description>Khronos OpenXR loader and headers required to build a Win32 or UWP OpenXR application</description>
+    <tags>native khronos openxr loader headers</tags>
+    <dependencies>
+      <dependency id="OpenXR.Headers" version="1.0.10.2" />
+    </dependencies>
+  </metadata>
+</package>

oxr/[Content_Types].xml

@@ -0,0 +1,10 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Types xmlns="http://schemas.openxmlformats.org/package/2006/content-types">
+  <Default Extension="rels" ContentType="application/vnd.openxmlformats-package.relationships+xml" />
+  <Default Extension="psmdcp" ContentType="application/vnd.openxmlformats-package.core-properties+xml" />
+  <Default Extension="props" ContentType="application/octet" />
+  <Default Extension="targets" ContentType="application/octet" />
+  <Default Extension="dll" ContentType="application/octet" />
+  <Default Extension="lib" ContentType="application/octet" />
+  <Default Extension="nuspec" ContentType="application/octet" />
+</Types>

oxr/_rels/.rels

@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">
+  <Relationship Type="http://schemas.microsoft.com/packaging/2010/07/manifest" Target="/OpenXR.Loader.nuspec" Id="R0D169365D22F5E6F" />
+  <Relationship Type="http://schemas.openxmlformats.org/package/2006/relationships/metadata/core-properties" Target="/package/services/metadata/core-properties/948f85fa57f345119150f5525085c62c.psmdcp" Id="R10D7CDDCA5670667" />
+</Relationships>

oxr/build/native/OpenXR.Loader.props

@@ -0,0 +1,5 @@
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <PropertyGroup>
+    <OpenXRLoaderPackageRoot>$(MSBuildThisFileDirectory)..\..\</OpenXRLoaderPackageRoot>
+  </PropertyGroup>
+</Project>

oxr/build/native/OpenXR.Loader.targets

@@ -0,0 +1,35 @@
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+
+    <Choose>
+        <When Condition="'$(ApplicationType)|$(ApplicationTypeRevision)' == 'Windows Store|10.0'">
+            <PropertyGroup>
+                <OpenXRLoaderBinaryRoot>$(OpenXRLoaderPackageRoot)native\$(Platform)_uwp\release</OpenXRLoaderBinaryRoot>
+            </PropertyGroup>
+        </When>
+        <Otherwise>
+            <PropertyGroup>
+                <OpenXRLoaderBinaryRoot>$(OpenXRLoaderPackageRoot)native\$(Platform)\release</OpenXRLoaderBinaryRoot>
+            </PropertyGroup>
+        </Otherwise>
+    </Choose>
+
+    <ItemDefinitionGroup>
+        <Link>
+            <AdditionalDependencies>%(AdditionalDependencies);$(OpenXRLoaderBinaryRoot)\lib\openxr_loader.lib</AdditionalDependencies>
+        </Link>
+    </ItemDefinitionGroup>
+
+    <!-- Copy the OpenXR loader DLL to the output directory and include in packaging -->
+    <ItemGroup Condition="'$(OpenXRSkipLoaderCopy)'!='true'">
+        <None Include="$(OpenXRLoaderBinaryRoot)\bin\openxr_loader.dll">
+            <Link>%(Filename)%(Extension)</Link>
+            <CopyToOutputDirectory>PreserveNewest</CopyToOutputDirectory>
+            <DeploymentContent>true</DeploymentContent>
+        </None>
+    </ItemGroup>
+
+    <Target Name="EnsurePropsImported" BeforeTargets="PrepareForBuild">
+        <Error Condition="'$(OpenXRLoaderPackageRoot)'==''" Text="OpenXRLoaderPackageRoot property missing. Project is malformed. Try removing and re-adding the NuGet reference." />
+    </Target>
+
+</Project>

oxr/package/services/metadata/core-properties/948f85fa57f345119150f5525085c62c.psmdcp

@@ -0,0 +1,9 @@
+<?xml version="1.0" encoding="utf-8"?>
+<coreProperties xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.openxmlformats.org/package/2006/metadata/core-properties">
+  <dc:creator>Khronos Group</dc:creator>
+  <dc:description>Khronos OpenXR loader and headers required to build a Win32 or UWP OpenXR application</dc:description>
+  <dc:identifier>OpenXR.Loader</dc:identifier>
+  <version>1.0.10.2</version>
+  <keywords>native khronos openxr loader headers</keywords>
+  <lastModifiedBy>NuGet, Version=5.4.0.3, Culture=neutral, PublicKeyToken=31bf3856ad364e35;Microsoft Windows NT 6.2.9200.0;.NET Framework 4.7.2</lastModifiedBy>
+</coreProperties>

tests/aa_shots.lua

@@ -0,0 +1,195 @@
+-- Driver: one scene, once per rung of the AA row.
+--
+-- The AA row is the one setting in this mod whose whole effect is a pixel
+-- wide, so it is also the one that cannot be judged from a description. This
+-- renders the SAME frame at each rung and writes one PNG per rung; put two of
+-- them side by side, magnified, and the row is either doing something or it
+-- is not.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/aa_shots.lua \
+--   SHOT_DIR=<dir> lovec.exe .
+--
+-- knobs (env):
+--   SHOT_DIR   output directory (created if missing)  (default "shots/aa")
+--   AA_MAP     map id                                 (default VIRIDIAN_CITY)
+--   AA_SPOT    "x,y[,facing]"                         (default 20,26,up)
+--   AA_RUNG    the voxel camera rung                  (default 5, the 75 one)
+--
+-- The scene defaults to a town at the LOW camera on purpose: roof ridges, the
+-- diagonal of a fence and a tree's silhouette against the sky are the edges
+-- that stair-step, and 75 degrees is the rung that puts the most of them at an
+-- angle to the pixel grid.
+--
+-- Determinism matters here for the same reason it does in voxel_shots_ab: the
+-- three shots differ ONLY by the row under test, or comparing them means
+-- nothing. The clock is pinned, the animated tile slots are frozen, the
+-- townsfolk are stopped where they stand, and the tilt-shift is held at zero
+-- (a gaussian over the frame would smear away the very edges being looked at).
+--
+-- Nothing here writes the player's options: the row is moved with
+-- ModSetting:sync, which moves the cached index and persists nothing.
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+  local OverworldState = require("src.world.OverworldController")
+
+  local ROOT = os.getenv("SHOT_DIR") or "shots/aa"
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[aa] DRAMATIC_SHAPE mod not loaded -- nothing to shoot")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local AntiAlias = V.require("AntiAlias")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+  local ShadowMap = V.require("ShadowMap")
+
+  local MAP = os.getenv("AA_MAP") or "VIRIDIAN_CITY"
+  local SPOT = os.getenv("AA_SPOT") or "20,26,up"
+  local RUNG = math.floor(tonumber(os.getenv("AA_RUNG")) or 5)
+  local sx, sy, sf = SPOT:match("^(%-?%d+),%s*(%-?%d+),?%s*(%a*)$")
+  sx, sy = tonumber(sx) or 20, tonumber(sy) or 26
+  if sf == "" then sf = "up" end
+
+  OverworldState.rollEncounter = function() return nil end
+
+  local NPC = require("src.world.NPC")
+  if not NPC.dramaticShapeAaFreeze then
+    local inner = NPC.update
+    function NPC:update(...)
+      self.frozen = true
+      return inner(self, ...)
+    end
+    NPC.dramaticShapeAaFreeze = true
+  end
+  pcall(love.math.setRandomSeed, 20260801)
+
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function cameraStill()
+    local o = game.overworld
+    local c = o and o.camera
+    if not c then return true end
+    local lx, ly, held = nil, nil, 0
+    for _ = 1, 300 do
+      if c.x == lx and c.y == ly then
+        held = held + 1
+        if held >= 10 then return true end
+      else
+        held = 0
+        lx, ly = c.x, c.y
+      end
+      U.wait(1)
+    end
+    return false
+  end
+
+  -- The camera PITCH, which is the one that caught this driver out. The tween
+  -- runs on wall-clock dt and Voxel.t reaching 1 is not the same instant the
+  -- angle stops moving, so the first shot of a run came out at 67 degrees
+  -- while the two after it were at 75 -- three frames that differ by the
+  -- camera, in a comparison whose entire subject is a pixel.
+  local function angleStill()
+    local last, held = nil, 0
+    for _ = 1, 600 do
+      if Voxel.angle == last then
+        held = held + 1
+        if held >= 10 then return true end
+      else
+        held = 0
+        last = Voxel.angle
+      end
+      U.wait(1)
+    end
+    return false
+  end
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    angleStill()
+    cameraStill()
+    -- the sun map is only redrawn when its inputs move, and the AA row is not
+    -- one of them -- so force one pass at the settled camera rather than
+    -- comparing a frame against a map fitted a few hundredths of a pixel ago
+    if ShadowMap.forget then ShadowMap.forget() end
+    U.wait(20)
+  end
+
+  DayNight.setting:sync("day")
+  U.teleport(game, MAP, sx, sy, sf)
+  Pipelines.setLevel("voxel", RUNG)
+  Pipelines.setLevel("tiltshift", 0)
+
+  -- Warm up before the FIRST shot, not just between them.
+  --
+  -- Neighbour maps are requested from inside the render itself
+  -- (VoxelScene.prefetch), so an empty build queue right after a teleport
+  -- means "nothing has been asked for yet", not "everything is here". The
+  -- first capture of a run came out with the map beyond Viridian missing --
+  -- a whole tree line absent from one frame of a three-way comparison, which
+  -- looks exactly like the row under test doing something enormous. Settling
+  -- twice lets the first render request the neighbourhood and the second
+  -- drain it.
+  settle()
+  settle()
+
+  local shots, missed = 0, 0
+  for _, samples in ipairs({ 0, 2, 4 }) do
+    AntiAlias.setting:sync(samples)
+    settle()
+    -- AA_TRACE=1 prints the state each shot was taken in. When two shots of a
+    -- run disagree by more than the row could account for, this is what says
+    -- which input moved -- it is how the camera-tween and the neighbour-mesh
+    -- settles above were both found.
+    if os.getenv("AA_TRACE") == "1" then
+      local Voxel3D = V.require("Voxel3D")
+      local o = game.overworld
+      local cw, chh = Voxel3D.size()
+      print(("[aa] trace samples=%d angle=%.6f fov=%.6f cell=%.4f canvas=%dx%d cam=(%.3f,%.3f) eye=(%.2f,%.2f,%.2f) factor=%.4f")
+        :format(samples, Voxel.angle or -1, Voxel3D.fovY or -1,
+                Voxel3D.cell or -1, cw or 0, chh or 0,
+                o and o.camera and o.camera.x or -1,
+                o and o.camera and o.camera.y or -1,
+                (Voxel3D.eye or {})[1] or 0, (Voxel3D.eye or {})[2] or 0,
+                (Voxel3D.eye or {})[3] or 0, AntiAlias.factor()))
+    end
+    local path = ("%s/aa_%d.png"):format(ROOT, samples)
+    game.capturePath = path
+    U.wait(6)
+    local f = io.open(path, "rb")
+    if f then
+      f:close()
+      shots = shots + 1
+      print(("[aa] %s  samples=%d"):format(path, samples))
+    else
+      missed = missed + 1
+      print("[aa] capture did not reach disk: " .. path)
+    end
+  end
+  -- left where it was found, so a run cannot leak a rung into the next one
+  AntiAlias.setting:sync(0)
+
+  print(("[aa] %d shots into %s (%d failed to reach disk)")
+    :format(shots, ROOT, missed))
+end

tests/bike_shop_shots.lua

@@ -0,0 +1,79 @@
+-- Scratch driver: shots of the Bike Shop showroom, for the bicycle
+-- voxelization.  Two viewpoints -- the north wall (the two bikes drawn
+-- INTO the wall band) and the showroom floor (the six standing bikes).
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/bike_shop_shots.lua \
+--   SHOT_DIR=.scratchpad/bikes AB_TAG=before lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/bikes")
+    .. "/" .. (os.getenv("AB_TAG") or "before")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[bike] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  -- cells: wall bikes ride cell row 0 (tile cols 1-3 and 6-8); the six
+  -- floor bikes stand in cell columns 0 and 2, rows 1-2 and 4-5
+  local SCENES = {
+    { x = 2, y = 2, face = "up",   label = "wall" },
+    { x = 3, y = 3, face = "up",   label = "room" },
+    { x = 2, y = 4, face = "left", label = "floor" },
+    { x = 3, y = 6, face = "up",   label = "wide" },
+    -- the two toolboxes, cells (6,6) and (7,7)
+    { x = 5, y = 6, face = "right", label = "tools" },
+    { x = 6, y = 4, face = "down",  label = "tools2" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    for _, rung in ipairs({ 3, 5 }) do
+      U.teleport(game, "BIKE_SHOP", s.x, s.y, s.face)
+      Pipelines.setLevel("voxel", rung)
+      Pipelines.setLevel("tiltshift", 0)
+      settle()
+      local path = ("%s/%s_v%d.png"):format(ROOT, s.label, rung)
+      game.capturePath = path
+      U.wait(6)
+      local f = io.open(path, "rb")
+      if f then f:close() shots = shots + 1
+      else print("[bike] capture missed: " .. path) end
+    end
+  end
+  print(("[bike] %d shots into %s"):format(shots, ROOT))
+end

tests/bills_desk_shots.lua

@@ -0,0 +1,77 @@
+-- Scratch driver: shots of Bill's desk, for the `bills_desk`
+-- voxelization.  The desk fills cells (1,4) and (2,4) of Bill's house
+-- with its chair in the walkable cell (1,5) below it, so these are the
+-- angles you can actually stand at: head-on from the floor two cells
+-- south, and from either flank.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/bills_desk_shots.lua \
+--   SHOT_DIR=.scratchpad/billsdesk AB_TAG=after lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/billsdesk")
+    .. "/" .. (os.getenv("AB_TAG") or "after")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[bills] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  local SCENES = {
+    { x = 1, y = 6, face = "up",    label = "headon" },
+    { x = 2, y = 6, face = "up",    label = "headon_e" },
+    { x = 4, y = 5, face = "left",  label = "east" },
+    { x = 0, y = 5, face = "right", label = "west" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    for _, rung in ipairs({ 3, 5 }) do
+      U.teleport(game, "BILLS_HOUSE", s.x, s.y, s.face)
+      Pipelines.setLevel("voxel", rung)
+      Pipelines.setLevel("tiltshift", 0)
+      settle()
+      local path = ("%s/%s_v%d.png"):format(ROOT, s.label, rung)
+      game.capturePath = path
+      U.wait(6)
+      local f = io.open(path, "rb")
+      if f then f:close() shots = shots + 1
+      else print("[bills] capture missed: " .. path) end
+    end
+  end
+  print(("[bills] %d shots into %s"):format(shots, ROOT))
+  love.event.quit()
+end

tests/chief_house_shots.lua

@@ -0,0 +1,81 @@
+-- Scratch driver: shots of the Celadon chief's house, for the display
+-- cabinet and long table voxelizations.  Three viewpoints -- the
+-- cabinet rank along the north wall, the long table in the middle of
+-- the room, and a wide shot with both in frame.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/chief_house_shots.lua \
+--   SHOT_DIR=.scratchpad/chief AB_TAG=after lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/chief")
+    .. "/" .. (os.getenv("AB_TAG") or "after")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[chief] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  -- the cabinets occupy cells 2..5 of rows 0-1; the long table cells
+  -- 2..5 of rows 3-4; the player walks rows 2 and 5
+  local SCENES = {
+    { x = 3, y = 2, face = "up",    label = "cabinets" },
+    { x = 5, y = 2, face = "up",    label = "bookcase" },
+    { x = 3, y = 5, face = "up",    label = "table" },
+    { x = 1, y = 5, face = "right", label = "wide" },
+    -- the same rank on CELADON_MANSION_1F, where it stands against the
+    -- interior partition and the grids start on an ODD tile row
+    { map = "CELADON_MANSION_1F", x = 2, y = 4, face = "up",
+      label = "mansion1f" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    for _, rung in ipairs({ 3, 5 }) do
+      U.teleport(game, s.map or "CELADON_CHIEF_HOUSE", s.x, s.y, s.face)
+      Pipelines.setLevel("voxel", rung)
+      Pipelines.setLevel("tiltshift", 0)
+      settle()
+      local path = ("%s/%s_v%d.png"):format(ROOT, s.label, rung)
+      game.capturePath = path
+      U.wait(6)
+      local f = io.open(path, "rb")
+      if f then f:close() shots = shots + 1
+      else print("[chief] capture missed: " .. path) end
+    end
+  end
+  print(("[chief] %d shots into %s"):format(shots, ROOT))
+end

tests/fp_shots.lua

@@ -0,0 +1,159 @@
+-- Scratch driver: shots of the 1ST (first-person) rung -- the rig standing
+-- in the player's head, billboards yawing to face it, the sky meeting the
+-- horizon, the shadow box following the look, water seen from eye level,
+-- and an interior with its figures.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/fp_shots.lua \
+--   SHOT_DIR=.scratchpad/fpshots lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/fp")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[fp] DRAMATIC_SHAPE mod not loaded")
+    return love.event.quit()
+  end
+  local V = handle.lib
+  local FirstPerson = V.require("FirstPerson")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+  local DayNight = V.require("DayNight")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 0
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if FirstPerson.blend >= 1 and Voxel.ready
+         and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  -- Teleport to the nearest WALKABLE cell: a guessed coordinate inside a
+  -- building footprint buries the eye in the geometry, which is what the
+  -- first cut of every Pallet shot did.
+  local function place(mapId, x, y)
+    U.teleport(game, mapId, x, y, "down")
+    local ow = game.stack:top()
+    local map = ow and ow.map
+    if not map or map:isWalkableCell(x, y) then return end
+    for r = 1, 8 do
+      for dy = -r, r do
+        for dx = -r, r do
+          if math.max(math.abs(dx), math.abs(dy)) == r then
+            local cx, cy = x + dx, y + dy
+            if map:inBounds(cx, cy) and map:isWalkableCell(cx, cy) then
+              U.teleport(game, mapId, cx, cy, "down")
+              print(("[fp] (%d,%d) not walkable; standing at (%d,%d)")
+                    :format(x, y, cx, cy))
+              return
+            end
+          end
+        end
+      end
+    end
+  end
+
+  -- yaw is a world bearing: 0 south, pi/2 east, pi north, -pi/2 west
+  local SCENES = {
+    -- Pallet Town, mid-street: houses, the lab, NPCs -- the town seen
+    -- from inside it, in each compass direction plus a diagonal
+    { map = "PALLET_TOWN", x = 13, y = 14, yaw = math.pi, label = "pallet_north" },
+    { map = "PALLET_TOWN", x = 13, y = 14, yaw = 0, label = "pallet_south" },
+    { map = "PALLET_TOWN", x = 9, y = 7, yaw = math.pi / 2, label = "pallet_east" },
+    { map = "PALLET_TOWN", x = 9, y = 7, yaw = 3 * math.pi / 4,
+      label = "pallet_diag" },
+    -- the shoreline: water at eye level, which is where the battle pass
+    -- says a low placed camera reads the reflection wrong -- the shot
+    -- decides whether 1ST keeps it
+    { map = "PALLET_TOWN", x = 9, y = 12, yaw = 0, label = "pallet_water" },
+    -- looking up: the sky's bands and the horizon line
+    { map = "PALLET_TOWN", x = 13, y = 14, yaw = math.pi,
+      pitch = -math.rad(25), label = "pallet_skyward" },
+    -- and down: the ground, the feet-level shadow
+    { map = "PALLET_TOWN", x = 13, y = 14, yaw = math.pi,
+      pitch = math.rad(45), label = "pallet_down" },
+    -- Route 1: grass rows and ledges from inside them
+    { map = "ROUTE_1", x = 10, y = 28, yaw = math.pi, label = "route1_north" },
+    -- an interior: the Center's counter, machines and couch figures
+    { map = "VIRIDIAN_POKECENTER", x = 3, y = 5, yaw = math.pi,
+      label = "center_north" },
+    { map = "VIRIDIAN_POKECENTER", x = 6, y = 4, yaw = -math.pi / 2,
+      label = "center_west" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    place(s.map, s.x, s.y)
+    Pipelines.setLevel("voxel", Voxel.FP_LEVEL)
+    Pipelines.setLevel("tiltshift", 0)
+    settle()
+    FirstPerson.yaw = s.yaw
+    FirstPerson.pitch = s.pitch or FirstPerson.PITCH_DEFAULT
+    U.wait(20)
+    if U.shot(game, ("%s/%s.png"):format(ROOT, s.label)) then
+      shots = shots + 1
+    end
+  end
+
+  -- one mid-blend shot: step the ladder onto 1ST from 75 and catch the
+  -- dive halfway
+  place("PALLET_TOWN", 13, 14)
+  Pipelines.setLevel("voxel", 5)
+  settle()
+  Pipelines.setLevel("voxel", Voxel.FP_LEVEL)
+  for _ = 1, 300 do
+    if FirstPerson.blend >= 0.5 then break end
+    U.wait(1)
+  end
+  if U.shot(game, ROOT .. "/blend_mid.png") then shots = shots + 1 end
+
+  -- ------- the free walk, exercised
+  --
+  -- Hold forward with the head yawed off-grid and confirm the player
+  -- GLIDES: the position moves along the look direction, lands off the
+  -- 16px grid (which no grid step can do), and the logical cell follows.
+  place("PALLET_TOWN", 13, 14)
+  Pipelines.setLevel("voxel", Voxel.FP_LEVEL)
+  settle()
+  local ow = game.stack:top()
+  local p = ow.player
+  FirstPerson.yaw = 3 * math.pi / 4       -- northeast, deliberately off-grid
+  FirstPerson.pitch = FirstPerson.PITCH_DEFAULT
+  local x0, y0, c0x, c0y = p.px, p.py, p.cellX, p.cellY
+  U.hold(game, "up", 90)
+  U.wait(5)
+  local moved = math.abs(p.px - x0) + math.abs(p.py - y0)
+  print(("[fp] walk: (%.1f,%.1f) cell(%d,%d) -> (%.1f,%.1f) cell(%d,%d)")
+        :format(x0, y0, c0x, c0y, p.px, p.py, p.cellX, p.cellY))
+  print(("[fp] walk moved %.1f px; off-grid: %s; diagonal: %s")
+        :format(moved,
+                tostring(p.px % 16 ~= 0 or p.py % 16 ~= 0),
+                tostring(math.abs(p.px - x0) > 8
+                         and math.abs(p.py - y0) > 8)))
+  if U.shot(game, ROOT .. "/walked.png") then shots = shots + 1 end
+
+  print(("[fp] %d shots into %s"):format(shots, ROOT))
+  love.event.quit()
+end

tests/heal_machine_shots.lua

@@ -0,0 +1,78 @@
+-- Scratch driver: shots of the Pokemon Center healing machines behind
+-- the counter, for the center_heal_machine voxelization.  The pair
+-- stands at cells (1,0):(2,1) and (6,0):(7,1) of every Center; the
+-- nurse aisle (row 2) is the row you can actually face them from, and
+-- the public floor south of the counter gives the wide view.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/heal_machine_shots.lua \
+--   SHOT_DIR=.scratchpad/healshots AB_TAG=after lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/healmachine")
+    .. "/" .. (os.getenv("AB_TAG") or "after")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[heal] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  local SCENES = {
+    { x = 1, y = 2, face = "up",   label = "west_head" },
+    { x = 2, y = 2, face = "up",   label = "west_keyboard" },
+    { x = 3, y = 2, face = "left", label = "west_side" },
+    { x = 6, y = 2, face = "up",   label = "east_head" },
+    { x = 3, y = 4, face = "up",   label = "wide" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    for _, rung in ipairs({ 3, 5 }) do
+      U.teleport(game, "VIRIDIAN_POKECENTER", s.x, s.y, s.face)
+      Pipelines.setLevel("voxel", rung)
+      Pipelines.setLevel("tiltshift", 0)
+      settle()
+      local path = ("%s/%s_v%d.png"):format(ROOT, s.label, rung)
+      game.capturePath = path
+      U.wait(6)
+      local f = io.open(path, "rb")
+      if f then f:close() shots = shots + 1
+      else print("[heal] capture missed: " .. path) end
+    end
+  end
+  print(("[heal] %d shots into %s"):format(shots, ROOT))
+  love.event.quit()
+end

tests/house_furniture_shots.lua

@@ -0,0 +1,98 @@
+-- Scratch driver: shots of the house dining tables and stools, for the
+-- band-table + no-desk-part voxelization.  Every generic home places the
+-- table at cells (3,3):(4,4) with four stools around it (Blue's house has
+-- Daisy seated at hers); Red's and the Copycat's ground floors place the
+-- same furniture one cell lower, with the potted plant CUTOUT standing on
+-- the tabletop -- the standee the table template must support, not
+-- swallow.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/house_furniture_shots.lua \
+--   SHOT_DIR=.scratchpad/housefurn AB_TAG=after lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/housefurn")
+    .. "/" .. (os.getenv("AB_TAG") or "after")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[housefurn] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  local SCENES = {
+    -- head on: below Blue's table looking north over a stool at it,
+    -- Daisy seated at the left one
+    { map = "BLUES_HOUSE", x = 3, y = 5, face = "up", label = "blues_front" },
+    -- from the east, table and both east stools in profile
+    { map = "BLUES_HOUSE", x = 6, y = 3, face = "left", label = "blues_side" },
+    -- from the north wall looking south down over the tabletop
+    { map = "BLUES_HOUSE", x = 4, y = 2, face = "down", label = "blues_over" },
+    -- close beside a stool: seat top, legs and the gap between them
+    { map = "BLUES_HOUSE", x = 2, y = 5, face = "up", label = "stool_close" },
+    -- Red's table head on from the south: the plant cutout standing on
+    -- the modelled tabletop
+    { map = "REDS_HOUSE_1F", x = 4, y = 6, face = "up", label = "reds_front" },
+    -- and from the east along the stool row, plant in profile
+    { map = "REDS_HOUSE_1F", x = 6, y = 4, face = "left", label = "reds_side" },
+    -- the Fan Club's four members' chairs round the boardroom table:
+    -- from the south of the west pair, both stools stacked in profile
+    { map = "POKEMON_FAN_CLUB", x = 1, y = 5, face = "up",
+      label = "club_west_pair" },
+    -- across the table from the west, both pairs and the octagon between
+    { map = "POKEMON_FAN_CLUB", x = 0, y = 3, face = "right",
+      label = "club_across" },
+    -- close on the east pair from the north, looking down over the seats
+    { map = "POKEMON_FAN_CLUB", x = 6, y = 2, face = "down",
+      label = "club_over" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    for _, rung in ipairs({ 3, 5 }) do
+      U.teleport(game, s.map, s.x, s.y, s.face)
+      Pipelines.setLevel("voxel", rung)
+      Pipelines.setLevel("tiltshift", 0)
+      settle()
+      local path = ("%s/%s_v%d.png"):format(ROOT, s.label, rung)
+      game.capturePath = path
+      U.wait(6)
+      local f = io.open(path, "rb")
+      if f then f:close() shots = shots + 1
+      else print("[housefurn] capture missed: " .. path) end
+    end
+  end
+  print(("[housefurn] %d shots into %s"):format(shots, ROOT))
+end

tests/mart_shots.lua

@@ -0,0 +1,76 @@
+-- Scratch driver: shots of a Poke Mart's clerk counter, for the cash
+-- register voxelization.  The register is drawn at cell (1,5) of the 4x4
+-- shop layout every Mart shares, in the middle of the counter's east arm,
+-- so these are the three angles you can actually stand at: head-on from
+-- the aisle, side-on from the east, and over the counter's south arm.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/mart_shots.lua \
+--   SHOT_DIR=.scratchpad/register AB_TAG=after lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/register")
+    .. "/" .. (os.getenv("AB_TAG") or "after")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[mart] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  local SCENES = {
+    { x = 1, y = 7, face = "up",   label = "aisle" },
+    { x = 2, y = 5, face = "left", label = "side" },
+    { x = 2, y = 6, face = "left", label = "over" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    for _, rung in ipairs({ 3, 5 }) do
+      U.teleport(game, "VIRIDIAN_MART", s.x, s.y, s.face)
+      Pipelines.setLevel("voxel", rung)
+      Pipelines.setLevel("tiltshift", 0)
+      settle()
+      local path = ("%s/%s_v%d.png"):format(ROOT, s.label, rung)
+      game.capturePath = path
+      U.wait(6)
+      local f = io.open(path, "rb")
+      if f then f:close() shots = shots + 1
+      else print("[mart] capture missed: " .. path) end
+    end
+  end
+  print(("[mart] %d shots into %s"):format(shots, ROOT))
+  love.event.quit()
+end

tests/mon_shots.lua

@@ -0,0 +1,71 @@
+-- Driver: one overworld-battle screenshot per species, the mon fighting
+-- ITSELF -- its back pic on the player's mark and its front pic on the
+-- enemy's, so a single frame shows both sprites the 3D mode draws for it.
+--
+-- The point is a visual sweep for pic glitches (holes the paper-fill missed,
+-- a silhouette cut wrong, a pin that leaves the mon floating), so every shot
+-- is staged identically: same map, same cells, same beat -- the battle menu,
+-- both HUD panels up. Whatever differs between two shots is the mon.
+--
+--   SHOT_DIR=.scratchpad/mon_shots \
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/mon_shots.lua love .
+--
+-- Files land as NNN_species.png in dex order.
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local DIR = os.getenv("SHOT_DIR") or ".scratchpad/mon_shots"
+  local Pokemon = require("src.pokemon.Pokemon")
+  local BattleState = require("src.battle.BattleState")
+
+  -- every real species the merged data carries, walked in dex order
+  local species = {}
+  for id, def in pairs(game.data.pokemon) do
+    if type(id) == "string" and type(def) == "table"
+       and def.dex and def.dex >= 1 and def.dex <= 151 then
+      species[#species + 1] = { id = id, dex = def.dex }
+    end
+  end
+  table.sort(species, function(a, b) return a.dex < b.dex end)
+  U.log(("%d species"):format(#species))
+
+  game.save.player.name = "RED"
+
+  for _, s in ipairs(species) do
+    -- level 50 both sides: high enough that nothing about the staging is
+    -- species-specific, and a wild battle never awards exp off a menu shot
+    game.save.party = { Pokemon.new(game.data, s.id, 50) }
+
+    U.teleport(game, "ROUTE_1", 5, 8, "down")
+    -- let the neighbourhood's meshes land so the first battle frame is the
+    -- real arena rather than the flat fallback
+    U.wait(60)
+
+    local battle = BattleState.newWild(game, s.id, 50)
+    battle.onFinish = function() end
+    game.overworld:pushBattle(battle)
+
+    -- the wipe, then tap through "Wild X appeared!" and the send-out until
+    -- the battle MENU is actually up -- a fixed tap count lands on whatever
+    -- beat the intro happened to be on, which is how a shot ends up with the
+    -- trainer still standing where the mon should be
+    U.wait(70)
+    for _ = 1, 200 do
+      if battle.phase == "menu" then break end
+      U.tap(game, "a")
+      U.wait(6)
+    end
+    if battle.phase ~= "menu" then
+      U.log(("STUCK before menu: %s (phase %s)"):format(s.id, tostring(battle.phase)))
+    end
+    -- let the send-out slide/ball beat finish so the mon is standing still
+    U.wait(40)
+    U.shot(game, ("%s/%03d_%s.png"):format(DIR, s.dex, s.id:lower()))
+
+    while game.stack:top() and game.stack:top() ~= game.overworld do
+      game.stack:pop()
+    end
+    U.wait(10)
+  end
+
+  U.log("done -- " .. DIR)
+end

tests/pic_dump.lua

@@ -0,0 +1,63 @@
+-- Driver: dump the exact pic textures a live 3D battle draws, per stage --
+-- the sprite as loaded (raw) and what picImage hands the billboard after the
+-- palette bake and BattlePics' paper fill (final). Diagnostic for pics that
+-- render with holes: whichever stage the transparency first appears in is
+-- the stage that made it.
+--
+--   SHOT_DIR=.scratchpad/pic_dump \
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/pic_dump.lua love .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local DIR = os.getenv("SHOT_DIR") or ".scratchpad/pic_dump"
+  local Pokemon = require("src.pokemon.Pokemon")
+  local BattleState = require("src.battle.BattleState")
+
+  local function save(img, path)
+    if not img then U.log("NIL image for " .. path) return end
+    local w, h = img:getDimensions()
+    local g = love.graphics
+    local prev = g.getCanvas()
+    local canvas = g.newCanvas(w, h, { dpiscale = 1 })
+    g.setCanvas(canvas)
+    g.clear(0, 0, 0, 0)
+    g.setBlendMode("replace", "premultiplied")
+    g.setColor(1, 1, 1, 1)
+    g.draw(img, 0, 0)
+    g.setCanvas(prev)
+    g.setBlendMode("alpha")
+    local f = assert(io.open(path, "wb"))
+    f:write(canvas:newImageData():encode("png"):getString())
+    f:close()
+  end
+
+  local SPECIES = os.getenv("PIC_SPECIES")
+  local list = {}
+  if SPECIES then
+    for id in SPECIES:gmatch("[^,%s]+") do list[#list + 1] = id:upper() end
+  else
+    list = { "PIKACHU", "SEEL", "BULBASAUR", "MEWTWO" }
+  end
+
+  for _, id in ipairs(list) do
+    game.save.party = { Pokemon.new(game.data, id, 50) }
+    U.teleport(game, "ROUTE_1", 5, 8, "down")
+    U.wait(30)
+    local battle = BattleState.newWild(game, id, 50)
+    battle.onFinish = function() end
+    game.overworld:pushBattle(battle)
+    U.wait(80)
+    local lo = id:lower()
+    save(battle.enemy.sprite, ("%s/%s_front_raw.png"):format(DIR, lo))
+    save(battle:picImage(battle.enemy.sprite), ("%s/%s_front_final.png"):format(DIR, lo))
+    save(battle.player.sprite, ("%s/%s_back_raw.png"):format(DIR, lo))
+    save(battle:picImage(battle.player.sprite), ("%s/%s_back_final.png"):format(DIR, lo))
+    U.log("dumped " .. id)
+    while game.stack:top() and game.stack:top() ~= game.overworld do
+      game.stack:pop()
+    end
+    U.wait(5)
+  end
+
+  U.log("done -- " .. DIR)
+  love.event.quit()
+end

tests/potted_plant_shots.lua

@@ -0,0 +1,91 @@
+-- Scratch driver: shots of the potted plants, for the plant standee
+-- voxelization.  Every Center places three side-by-side pairs on its
+-- bottom row -- crowns at cells (0,6)/(1,6), (6,6)/(7,6), (12,6)/(13,6),
+-- pots below at y=7 -- and INDIGO_PLATEAU_LOBBY (the MART tileset id,
+-- same atlas) lines four of them along its hall at cells (12,10)..(15,10).
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/potted_plant_shots.lua \
+--   SHOT_DIR=.scratchpad/plants AB_TAG=after lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/plants")
+    .. "/" .. (os.getenv("AB_TAG") or "after")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[plant] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  local SCENES = {
+    -- east of the left pair, looking west along the bottom row: both
+    -- plants in profile, crown overhang and pot silhouette side-on
+    { map = "VIRIDIAN_POKECENTER", x = 3, y = 6, face = "left",
+      label = "pair_side" },
+    -- north of the left pair, looking south down over the crowns
+    { map = "VIRIDIAN_POKECENTER", x = 1, y = 5, face = "down",
+      label = "pair_over" },
+    -- head on: standing below the middle pair looking north at it
+    { map = "VIRIDIAN_POKECENTER", x = 6, y = 7, face = "up",
+      label = "pair_front" },
+    -- close up beside the east pair's pot
+    { map = "VIRIDIAN_POKECENTER", x = 11, y = 7, face = "right",
+      label = "close" },
+    -- the Plateau lobby's row of four (MART tileset id), along the row
+    { map = "INDIGO_PLATEAU_LOBBY", x = 11, y = 10, face = "right",
+      label = "lobby_row" },
+    -- and head on from the hall below
+    { map = "INDIGO_PLATEAU_LOBBY", x = 13, y = 12, face = "up",
+      label = "lobby_front" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    for _, rung in ipairs({ 3, 5 }) do
+      U.teleport(game, s.map, s.x, s.y, s.face)
+      Pipelines.setLevel("voxel", rung)
+      Pipelines.setLevel("tiltshift", 0)
+      settle()
+      local path = ("%s/%s_v%d.png"):format(ROOT, s.label, rung)
+      game.capturePath = path
+      U.wait(6)
+      local f = io.open(path, "rb")
+      if f then f:close() shots = shots + 1
+      else print("[plant] capture missed: " .. path) end
+    end
+  end
+  print(("[plant] %d shots into %s"):format(shots, ROOT))
+end

tests/roof_curve_shots.lua

@@ -0,0 +1,80 @@
+-- Scratch driver: the Cerulean gym and the houses beside it, shot at
+-- several camera rungs with V-CURVE walked OFF..3, to see what the world
+-- bend does to a building's roof.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/roof_curve_shots.lua \
+--   SHOT_DIR=.scratchpad/roofcurve AB_TAG=before lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/roofcurve")
+    .. "/" .. (os.getenv("AB_TAG") or "after")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[roof] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+  local WorldCurve = V.require("WorldCurve")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(30)
+  end
+
+  -- the gym door is CERULEAN_CITY (30,19); the bike shop and the row of
+  -- houses along the west side give a second, smaller roof in frame
+  local SCENES = {
+    { map = "CERULEAN_CITY", x = 30, y = 20, face = "up",   label = "gym" },
+    { map = "CERULEAN_CITY", x = 27, y = 21, face = "up",   label = "gymwide" },
+    { map = "PALLET_TOWN",   x = 5,  y = 6,  face = "up",   label = "house" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    for _, rung in ipairs({ 3, 5 }) do
+      for _, curve in ipairs({ 0, 3 }) do
+        U.teleport(game, s.map, s.x, s.y, s.face)
+        Pipelines.setLevel("voxel", rung)
+        Pipelines.setLevel("tiltshift", 0)
+        WorldCurve.setting:setIndex(curve + 1, game)
+        settle()
+        local path = ("%s/%s_v%d_c%d.png"):format(ROOT, s.label, rung, curve)
+        game.capturePath = path
+        U.wait(8)
+        local f = io.open(path, "rb")
+        if f then f:close() shots = shots + 1
+        else print("[roof] capture missed: " .. path) end
+      end
+    end
+  end
+  print(("[roof] %d shots into %s"):format(shots, ROOT))
+  love.event.quit()
+end

tests/roof_span_probe.lua

@@ -0,0 +1,47 @@
+-- Scratch probe: how long do a building model's merged quads get?
+--
+-- A quad's longest world-space edge is what decides how far its CHORD
+-- falls below the world curve's parabola, so this is the number that says
+-- whether the bend can crack the mesh open.
+--
+--   BUILD_MAP=CERULEAN_CITY POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/roof_span_probe.lua lovec .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local mapId = os.getenv("BUILD_MAP") or "CERULEAN_CITY"
+  U.teleport(game, mapId, tonumber(os.getenv("BUILD_X") or "30"),
+             tonumber(os.getenv("BUILD_Y") or "20"), "up")
+  U.wait(30)
+
+  local V = game.mods.exports["DRAMATIC_SHAPE"]
+  V = V and V.lib
+  local Structures = V and V.require("Structures")
+  local ow = game.overworld
+  if not (Structures and ow and ow.map) then
+    print("[span] mod or map unavailable")
+    love.event.quit()
+    return
+  end
+  local S = Structures.forMap(ow.map)
+  local hist, worst = {}, 0
+  for _, q in ipairs(S.objectQuads) do
+    local dx = math.max(q[1][1], q[2][1], q[3][1], q[4][1])
+             - math.min(q[1][1], q[2][1], q[3][1], q[4][1])
+    local dz = math.max(q[1][3], q[2][3], q[3][3], q[4][3])
+             - math.min(q[1][3], q[2][3], q[3][3], q[4][3])
+    local dy = math.max(q[1][2], q[2][2], q[3][2], q[4][2])
+             - math.min(q[1][2], q[2][2], q[3][2], q[4][2])
+    local span = math.max(dx, dz, dy)
+    local bucket = span <= 8 and "<=8" or (span <= 16 and "<=16"
+                  or (span <= 32 and "<=32" or (span <= 64 and "<=64" or ">64")))
+    bucket = bucket .. (q.own and " bld" or " prop")
+    hist[bucket] = (hist[bucket] or 0) + 1
+    if span > worst then worst = span end
+  end
+  print(("[span] %d object quads, longest edge %d px"):format(#S.objectQuads, worst))
+  for _, b in ipairs({ "<=8", "<=16", "<=32", "<=64", ">64" }) do
+    for _, kind in ipairs({ " bld", " prop" }) do
+      print(("[span]   %-10s %d"):format(b .. kind, hist[b .. kind] or 0))
+    end
+  end
+  love.event.quit()
+end

tests/round_regress_shots.lua

@@ -0,0 +1,75 @@
+-- Scratch driver: one shot of every OTHER user of the round-hull builder
+-- (tree canopies, boulders, hedges, stumps, the Center planter), to check
+-- that the `can` class's base cut is the identity it is supposed to be for
+-- everything that does not ask for it.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/round_regress_shots.lua \
+--   SHOT_DIR=.scratchpad/round AB_TAG=after lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/round")
+    .. "/" .. (os.getenv("AB_TAG") or "after")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then return end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  local SCENES = {
+    { map = "VIRIDIAN_FOREST", x = 16, y = 20, face = "up",   label = "forest" },
+    { map = "PEWTER_GYM",      x = 4,  y = 10, face = "up",   label = "boulders" },
+    { map = "CELADON_GYM",     x = 4,  y = 8,  face = "up",   label = "hedges" },
+    { map = "VIRIDIAN_POKECENTER", x = 6, y = 5, face = "up", label = "planter" },
+    { map = "PALLET_TOWN",     x = 5,  y = 8,  face = "up",   label = "trees" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    local ok = pcall(U.teleport, game, s.map, s.x, s.y, s.face)
+    if ok then
+      Pipelines.setLevel("voxel", 5)
+      Pipelines.setLevel("tiltshift", 0)
+      settle()
+      local path = ("%s/%s.png"):format(ROOT, s.label)
+      game.capturePath = path
+      U.wait(6)
+      local f = io.open(path, "rb")
+      if f then f:close() shots = shots + 1
+      else print("[round] capture missed: " .. path) end
+    else
+      print("[round] teleport failed: " .. s.map)
+    end
+  end
+  print(("[round] %d shots into %s"):format(shots, ROOT))
+end

tests/route1_candidates.lua

@@ -0,0 +1,218 @@
+-- Driver: propose and photograph several battle arenas for ONE map.
+--
+-- data/battle_arenas.lua holds a single authored spot per area, chosen by
+-- arena_pick's nearest-to-the-middle search and then looked at. This is the
+-- other half of that job: when the shipped spot is up for review, it lays out
+-- the ALTERNATIVES -- every arena on the map both mons can be seen in, spread
+-- along the map so the shortlist is places rather than neighbours -- and
+-- stages a real battle in each so they can be compared by eye.
+--
+--   SHOT_DIR=.scratchpad/route1_candidates CAND_MAP=ROUTE_1 CAND_N=5 \
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/route1_candidates.lua love .
+--
+-- CAND_MAP is the map id (default ROUTE_1), CAND_N how many to photograph.
+-- One `CAND` line per shot, ready to paste into the data file, plus a PNG
+-- named for its corner and shape.
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local DIR = os.getenv("SHOT_DIR") or ".scratchpad/route1_candidates"
+  local MAP = os.getenv("CAND_MAP") or "ROUTE_1"
+  local WANT = tonumber(os.getenv("CAND_N") or "") or 5
+  local Pokemon = require("src.pokemon.Pokemon")
+  local BattleState = require("src.battle.BattleState")
+
+  game.save.party = { Pokemon.new(game.data, "CHARIZARD", 45) }
+  game.save.player.name = "RED"
+
+  local exports = game.mods and game.mods.exports
+  local lib = exports and exports.DRAMATIC_SHAPE and exports.DRAMATIC_SHAPE.lib
+  if not lib then
+    U.log("DRAMATIC_SHAPE is not loaded -- enable it and run again")
+    return
+  end
+  local Arena = lib.require("BattleArena")
+  local Battles = lib.require("OverworldBattle")
+
+  U.teleport(game, MAP, 1, 1, "down")
+  local map = game.overworld.map
+  U.log(("%s is %dx%d cells"):format(MAP, map.widthCells, map.heightCells))
+
+  -- ------- every arena the map can offer
+  --
+  -- BattleArena.search answers "the nearest one", which is the wrong question
+  -- for a shortlist -- it returns one spot and hides the rest. So walk the
+  -- same grid ourselves and keep them all, tagged with whether the pair would
+  -- actually be SEEN there (Arena.clearance), because an obstructed spot is
+  -- not a candidate no matter how good the ground looks.
+  --
+  -- The map's outermost cells are its CONNECTION BORDER -- the strip the
+  -- neighbouring map is drawn into, walkable so the player can step across.
+  -- Ground there passes every test and is still the wrong answer: a fight
+  -- staged on it happens at the edge of the world with the border ring's tree
+  -- wall at the mons' backs, and every spot in the strip looks like every
+  -- other one. CAND_MARGIN keeps the shortlist on the route proper.
+  local MARGIN = tonumber(os.getenv("CAND_MARGIN") or "") or 2
+  local cands = {}
+  for _, shape in ipairs(Arena.SHAPES) do
+    for y = MARGIN, map.heightCells - shape.h - MARGIN do
+      for x = MARGIN, map.widthCells - shape.w - MARGIN do
+        local fits = true
+        for cy = y, y + shape.h - 1 do
+          for cx = x, x + shape.w - 1 do
+            if not Arena.openCell(map, cx, cy, false) then fits = false break end
+          end
+          if not fits then break end
+        end
+        if fits then
+          local a = Arena.at(x, y, shape.id)
+          if a and Arena.clearance(map, a) then
+            cands[#cands + 1] = { x = x, y = y, shape = shape.id,
+                                  mx = x + (shape.w - 1) / 2,
+                                  my = y + (shape.h - 1) / 2 }
+          end
+        end
+      end
+    end
+  end
+  U.log(("%d clear arenas on %s"):format(#cands, MAP))
+  if #cands == 0 then U.log("done -- nothing to propose") return end
+
+  for _, c in ipairs(cands) do
+    U.log(("  fit  %d,%d %s"):format(c.x, c.y, c.shape))
+  end
+
+  -- CAND_AT=x,y,shape;x,y,shape;... photographs an explicit shortlist instead
+  -- of the spread one. The spread is a first pass over ground the clearance
+  -- test approved, and that test measures terrain height along the sightline
+  -- only -- it has no opinion on a hedge sitting in the apron row between the
+  -- camera and the near mon, which is the failure that keeps turning up. So
+  -- the loop is: spread, look, then re-shoot the survivors and the
+  -- replacements by hand.
+  local explicit = os.getenv("CAND_AT")
+  if explicit and explicit ~= "" then
+    local list = {}
+    for spot in explicit:gmatch("[^;]+") do
+      local x, y, s = spot:match("^%s*(%-?%d+)%s*,%s*(%-?%d+)%s*,%s*(%a+)%s*$")
+      if x then
+        list[#list + 1] = { x = tonumber(x), y = tonumber(y), shape = s }
+      else
+        U.log("BAD CAND_AT entry: " .. spot)
+      end
+    end
+    cands = list
+    WANT = #list
+    U.log(("%d spots given explicitly"):format(#list))
+  end
+
+  local function shapeOf(id)
+    for _, s in ipairs(Arena.SHAPES) do if s.id == id then return s end end
+  end
+  for _, c in ipairs(cands) do
+    local s = shapeOf(c.shape)
+    c.mx = c.x + ((s and s.w or 1) - 1) / 2
+    c.my = c.y + ((s and s.h or 1) - 1) / 2
+  end
+
+  -- ------- thin them down to a shortlist that is actually a CHOICE
+  --
+  -- Adjacent corners are the same patch of ground shifted a cell, so a naive
+  -- top-N is five photographs of one place, and pure farthest-point selection
+  -- goes straight to the extremes -- which on a route means the ends, where
+  -- the ground is emptiest and the shots are least distinguishable.
+  --
+  -- So: spread along the route's LONG AXIS, one pick per band, and within a
+  -- band take the spot nearest the middle of the road. The road is measured
+  -- rather than assumed -- the median cross-axis position of everywhere a
+  -- fight fits IS the lane, on a map whose walkable ground is mostly lane.
+  local horizontal = map.widthCells > map.heightCells
+  local function along(c) return horizontal and c.mx or c.my end
+  local function across(c) return horizontal and c.my or c.mx end
+
+  local xs = {}
+  for _, c in ipairs(cands) do xs[#xs + 1] = across(c) end
+  table.sort(xs)
+  local road = xs[math.ceil(#xs / 2)]
+  U.log(("road runs %s, centre of the lane is %s = %.1f")
+        :format(horizontal and "east-west" or "north-south",
+                horizontal and "y" or "x", road))
+
+  local lo, hi = math.huge, -math.huge
+  for _, c in ipairs(cands) do
+    lo, hi = math.min(lo, along(c)), math.max(hi, along(c))
+  end
+
+  -- an explicit shortlist is already the answer; the spread below would only
+  -- thin it, and its overlap rule would silently drop two spots deliberately
+  -- asked for a cell apart
+  local picked, taken = {}, {}
+  for band = 1, (explicit and explicit ~= "") and 0 or WANT do
+    -- band centres, not band edges: the first and last picks sit inside the
+    -- route rather than on its two connection mouths
+    local target = lo + (hi - lo) * (band - 0.5) / WANT
+    local best, bestScore
+    for _, c in ipairs(cands) do
+      if not taken[c] then
+        local da = along(c) - target
+        local dr = across(c) - road
+        -- distance from the band centre, plus a heavier penalty for being off
+        -- the lane; wide arenas are worth a detour, being the shot this mode
+        -- is framed for
+        local score = da * da + 4 * dr * dr - (c.shape == "wide" and 100 or 0)
+        if not bestScore or score < bestScore then best, bestScore = c, score end
+      end
+    end
+    if best then
+      picked[#picked + 1] = best
+      -- everything overlapping the pick is off the table, so two bands whose
+      -- best spots touch cannot return the same patch of ground twice
+      for _, c in ipairs(cands) do
+        if math.abs(along(c) - along(best)) < 3
+           and math.abs(across(c) - across(best)) < 3 then
+          taken[c] = true
+        end
+      end
+    end
+  end
+
+  if #picked == 0 then picked = cands end
+
+  -- north to south (or west to east), so the filenames read along the route
+  table.sort(picked, function(a, b)
+    if along(a) ~= along(b) then return along(a) < along(b) end
+    return across(a) < across(b)
+  end)
+
+  for i, c in ipairs(picked) do
+    U.log(("CAND %d  [%q] = { x = %d, y = %d, shape = %q },")
+          :format(i, MAP, c.x, c.y, c.shape))
+    -- forced through the authored-entry seam, so what gets staged is exactly
+    -- this spot rather than whatever the search would pick from the player's
+    -- cell
+    Arena.setOverride(MAP, { x = c.x, y = c.y, shape = c.shape })
+    local staged = Arena.find(map, 0, 0, false)
+    if not staged then
+      U.log(("SKIP %d -- override did not stage"):format(i))
+    else
+      game.overworld.player.cellX = staged.playerCell[1]
+      game.overworld.player.cellY = staged.playerCell[2]
+      U.wait(90)                              -- let the meshes land
+      local battle = BattleState.newWild(game, "NIDORINO", 20)
+      battle.onFinish = function() end
+      game.overworld:pushBattle(battle)
+      U.wait(70)
+      for _ = 1, 14 do U.tap(game, "a"); U.wait(8) end
+      local got = Battles.arena()
+      U.log(("SHOT %d  staged at %s,%s"):format(i, tostring(got and got.x),
+                                                tostring(got and got.y)))
+      U.shot(game, ("%s/%d_%s_x%d_y%d_%s.png")
+                   :format(DIR, i, MAP:lower(), c.x, c.y, c.shape))
+      while game.stack:top() and game.stack:top() ~= game.overworld do
+        game.stack:pop()
+      end
+      U.wait(6)
+    end
+  end
+  Arena.setOverride(MAP, nil)
+
+  U.log("done -- " .. DIR)
+end

tests/shelf_relief_shots.lua

@@ -0,0 +1,92 @@
+-- Scratch driver: shots of the `bookcase` class across the tilesets that
+-- pin it, for the shelf-front relief.  Two of them are NOT shelves --
+-- the League's gate walls and the terraces on PLATEAU -- and are here as
+-- the control: their courses run edge to edge, so nothing should sink.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/shelf_relief_shots.lua \
+--   SHOT_DIR=.scratchpad/shelves AB_TAG=before lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/shelves")
+    .. "/" .. (os.getenv("AB_TAG") or "before")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[shelf] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  local SCENES = {
+    { map = "OAKS_LAB",           x = 7, y = 2, face = "up", label = "dojo_lab" },
+    { map = "CELADON_MANSION_2F", x = 2, y = 4, face = "up", label = "mansion_2f" },
+    { map = "CELADON_MART_2F",    x = 5, y = 5, face = "up", label = "lobby_mart" },
+    { map = "MUSEUM_1F",          x = 2, y = 4, face = "up", label = "museum" },
+    { map = "VIRIDIAN_MART",      x = 3, y = 5, face = "up", label = "mart" },
+    { map = "SS_ANNE_CAPTAINS_ROOM", x = 5, y = 2, face = "up", label = "ship" },
+    -- the controls, both of them tilesets that borrow the collapse for
+    -- something that is NOT a shelf and say so with `bookcase_relief =
+    -- false`: the League's masonry gate walls, and Bill's transporter
+    -- drums.  Nothing in either may move.
+    { map = "INDIGO_PLATEAU",     x = 2, y = 5, face = "up", label = "plateau" },
+    { map = "BILLS_HOUSE",        x = 2, y = 3, face = "up", label = "bills" },
+    -- the house shelves: pinned `desk`, NOT `bookcase`, so they go
+    -- through the world mesher's box fold and this relief never reaches
+    -- them.  Here to show the gap.
+    { map = "REDS_HOUSE_1F",      x = 1, y = 2, face = "up", label = "reds" },
+    { map = "BLUES_HOUSE",        x = 1, y = 2, face = "up", label = "blues" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    local ok = pcall(U.teleport, game, s.map, s.x, s.y, s.face)
+    -- twice: the first load of the session has no mesh to settle against
+    pcall(U.teleport, game, s.map, s.x, s.y, s.face)
+    if ok then
+      Pipelines.setLevel("voxel", 5)
+      Pipelines.setLevel("tiltshift", 0)
+      settle()
+      local path = ("%s/%s.png"):format(ROOT, s.label)
+      game.capturePath = path
+      U.wait(6)
+      local f = io.open(path, "rb")
+      if f then f:close() shots = shots + 1
+      else print("[shelf] capture missed: " .. path) end
+    else
+      print("[shelf] teleport failed: " .. s.map)
+    end
+  end
+  print(("[shelf] %d shots into %s"):format(shots, ROOT))
+end

tests/ship_can_shots.lua

@@ -0,0 +1,78 @@
+-- Scratch driver: shots of the SS Anne's galley barrels, which are Lt.
+-- Surge's trash can redrawn on the ship atlas.  Three down the kitchen's
+-- east wall at cells (13,5)/(13,7)/(13,9), one in the captain's room at
+-- (4,1), and one each in the two ship-interior houses at (7,7).
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/ship_can_shots.lua \
+--   SHOT_DIR=.scratchpad/ssanne AB_TAG=after lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/ssanne")
+    .. "/" .. (os.getenv("AB_TAG") or "after")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[ship] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  local SCENES = {
+    { map = "SS_ANNE_KITCHEN",       x = 12, y = 11, face = "up",    label = "galley_up" },
+    { map = "SS_ANNE_KITCHEN",       x = 12, y = 3,  face = "down",  label = "galley_down" },
+    { map = "SS_ANNE_KITCHEN",       x = 11, y = 7,  face = "right", label = "galley_side" },
+    { map = "SS_ANNE_CAPTAINS_ROOM", x = 4, y = 4,   face = "up",    label = "captain" },
+    { map = "CERULEAN_BADGE_HOUSE",  x = 6, y = 7,   face = "right", label = "house" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    local ok = pcall(U.teleport, game, s.map, s.x, s.y, s.face)
+    if ok then
+      Pipelines.setLevel("voxel", 5)
+      Pipelines.setLevel("tiltshift", 0)
+      settle()
+      local path = ("%s/%s.png"):format(ROOT, s.label)
+      game.capturePath = path
+      U.wait(6)
+      local f = io.open(path, "rb")
+      if f then f:close() shots = shots + 1
+      else print("[ship] capture missed: " .. path) end
+    else
+      print("[ship] teleport failed: " .. s.map)
+    end
+  end
+  print(("[ship] %d shots into %s"):format(shots, ROOT))
+end

tests/sky_ramp_probe.lua

@@ -0,0 +1,55 @@
+-- Driver: prove the banded sky still paints from the ramp texture.
+--
+-- The bands used to reach the shader as `uniform vec3 bands[8]`, which on
+-- Android delivered only its first few slots and painted the rest of the sky
+-- black (see lib/Sky.lua, rampFor).  They are a texture now.  This checks the
+-- three things that swap could have broken, on the machine it CAN be checked
+-- on: that the shader still compiles, that the ramp is built and is one texel
+-- per band, and that what lands on screen is still a gradient that pales
+-- downward rather than a flat plate or a black one.
+--
+--   SHOT_DIR=.scratchpad/skyramp POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/sky_ramp_probe.lua love .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local DIR = os.getenv("SHOT_DIR") or ".scratchpad/skyramp"
+
+  local exports = game.mods and game.mods.exports
+  local lib = exports and exports.DRAMATIC_SHAPE and exports.DRAMATIC_SHAPE.lib
+  if not lib then
+    U.log("DRAMATIC_SHAPE is not loaded -- enable it and run again")
+    return
+  end
+  local Sky = lib.require("Sky")
+  local DayNight = lib.require("DayNight")
+
+  -- which copy of the mod is actually live: only the ramp build has this
+  U.log("live copy has _rampFor:", tostring(Sky._rampFor ~= nil))
+  U.log("shader compiled:", tostring(Sky._getShader() ~= nil))
+
+  U.teleport(game, "PALLET_TOWN", 12, 10, "up")
+  require("src.render.Pipelines").setLevel("voxel", 5)
+  U.wait(150)
+
+  for _, phase in ipairs({ "day", "dusk", "night" }) do
+    DayNight.setting:sync(phase)
+    DayNight.update(0)
+    U.wait(30)
+
+    local bands = Sky.bands()
+    local ramp = Sky._rampFor and Sky._rampFor(bands)
+    local w = ramp and ramp:getWidth() or -1
+    U.log(("%s: %d bands, ramp %dx%d"):format(
+      phase, #bands, w, ramp and ramp:getHeight() or -1))
+    -- one texel per band is the whole contract: the shader divides by `count`
+    -- and samples texel centres, so a ramp of any other width samples between
+    -- bands or off the end
+    if w ~= #bands then U.log("FAIL ramp width does not match band count") end
+    -- and the ramp is the ramp: the same table gives the same image back
+    if ramp ~= Sky._rampFor(bands) then U.log("FAIL ramp rebuilt per call") end
+
+    U.shot(game, ("%s/%s.png"):format(DIR, phase))
+  end
+
+  DayNight.setting:sync("day")
+  U.log("done -- " .. DIR)
+end

tests/trash_can_shots.lua

@@ -0,0 +1,80 @@
+-- Scratch driver: shots of Vermilion Gym's trash cans, for the trash can
+-- voxelization.  The fifteen cans stand on odd cell columns 1..9 in cell
+-- rows 7, 9 and 11; the sixteenth is up at cell (6,1) beside the leader's
+-- platform.  Even columns are open floor, so the player can be parked
+-- between two cans and look along a row.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/trash_can_shots.lua \
+--   SHOT_DIR=.scratchpad/cans AB_TAG=before lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/cans")
+    .. "/" .. (os.getenv("AB_TAG") or "before")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[can] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync("day")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  local SCENES = {
+    -- head on into the middle of the field, cans left, right and ahead
+    { x = 4, y = 12, face = "up",    label = "field" },
+    -- close up: standing between two cans of the bottom row
+    { x = 2, y = 11, face = "left",  label = "close" },
+    -- along the row, so the cans line up in depth
+    { x = 4, y = 13, face = "up",    label = "row" },
+    -- from the north, looking back down over all three rows
+    { x = 4, y = 6,  face = "down",  label = "over" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    for _, rung in ipairs({ 3, 5 }) do
+      U.teleport(game, "VERMILION_GYM", s.x, s.y, s.face)
+      Pipelines.setLevel("voxel", rung)
+      Pipelines.setLevel("tiltshift", 0)
+      settle()
+      local path = ("%s/%s_v%d.png"):format(ROOT, s.label, rung)
+      game.capturePath = path
+      U.wait(6)
+      local f = io.open(path, "rb")
+      if f then f:close() shots = shots + 1
+      else print("[can] capture missed: " .. path) end
+    end
+  end
+  print(("[can] %d shots into %s"):format(shots, ROOT))
+end

tests/voxel_bench.lua

@@ -0,0 +1,246 @@
+-- Driver: the A/B performance benchmark.
+--
+-- One scripted, deterministic session that exercises the three things the
+-- mod is slow at, and writes the numbers to a JSON file so two runs can be
+-- diffed:
+--
+--   1. LOADING IN      -- engaging the mode from flat: shader compiles,
+--                         canvas allocations, the first map's mesh, its
+--                         atlas bakes and its glass mask, all at once.
+--   2. A NEW AREA      -- walking Pallet -> Route 1 -> Viridian with cold
+--                         caches, then walking the SAME route again with
+--                         them warm. The gap between the two is the
+--                         complaint; closing it is the fix.
+--   3. A LOW CAMERA    -- standing still at each pitch rung. The 75 degree
+--                         rung puts the horizon in frame, which triples the
+--                         sun frustum and hands the sky its disc to draw.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/voxel_bench.lua \
+--   DS_PERF=1 BENCH_TAG=baseline lovec.exe .
+--
+-- knobs (env):
+--   DS_PERF     must be set, or lib/Perf.lua stays dark and measures nothing
+--   BENCH_TAG   output name, ds_bench/<tag>.json     (default "run")
+--   BENCH_HOLD  frames to walk per leg              (default 900)
+--
+-- THREE THINGS THIS RUN CONTROLS FOR, because a benchmark that does not is
+-- measuring the weather:
+--
+--   * VSYNC OFF. With it on every frame costs exactly one refresh interval
+--     and the whole exercise reads as 16.7ms flat, saving or no saving.
+--   * THE CLOCK PINNED to day. The day/night cycle changes the sky, the sun
+--     angle, the shadow frustum and whether windows are lit -- so an
+--     unpinned run compares two different scenes.
+--   * ENCOUNTERS OFF. A wild battle mid-walk derails the route and charges
+--     its frames to whichever map the script thought it was on. Stubbed on
+--     the state class for this process only; nothing is written to disk.
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+  local OverworldState = require("src.world.OverworldController")
+
+  local TAG = os.getenv("BENCH_TAG") or "run"
+  -- Route 1 is 36 cells tall and a walk step is 16 frames, so a leg that
+  -- means to reach Viridian needs about 1200 -- short of that the "new
+  -- area" the benchmark is named for never gets entered.
+  local HOLD = math.floor(tonumber(os.getenv("BENCH_HOLD")) or 1300)
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[bench] DRAMATIC_SHAPE mod not loaded -- nothing to measure")
+    return
+  end
+  local V = handle.lib
+  local Perf = V.require("Perf")
+  if not Perf.enabled then
+    print("[bench] DS_PERF is not set -- run with DS_PERF=1 or this measures nothing")
+    return
+  end
+  local loadBytes = V.loadBytes
+  local Structures = V.require("Structures")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Buildings = V.require("Buildings")
+  local DayNight = V.require("DayNight")
+  local VoxelScene = V.require("VoxelScene")
+
+  -- module internals worth naming that the mod does not time itself
+  Perf.wrap(Structures, "forMap", "Structures.forMap")
+  Perf.wrap(Buildings, "build", "Buildings.build")
+  Perf.wrap(ChunkMesher, "pump", "ChunkMesher.pump")
+  Perf.wrap(VoxelScene, "render", "VoxelScene.render")
+
+  if love.window and love.window.setVSync then
+    pcall(love.window.setVSync, 0)
+  end
+  DayNight.setting:sync("day")
+  OverworldState.rollEncounter = function() return nil end
+
+  -- ---- the run ------------------------------------------------------
+
+  local function seg(name)
+    Perf.setSegment(name)
+    -- the frame that STRADDLES a segment boundary belongs to neither: it
+    -- carries the teleport, the level change or the report print that
+    -- opened it, and charging that to the new segment libels it
+    Perf.resync()
+  end
+
+  local function settle(frames)
+    Perf.setSegment(nil)
+    U.wait(frames or 60)
+    Perf.resync()
+  end
+
+  -- Hold a direction, attributing each frame to the map the player is
+  -- STANDING ON as it lands. Crossing a seam mid-leg is the whole point of
+  -- the walk, so the segment has to follow the player rather than the
+  -- script's idea of where they are.
+  local function walk(dir, frames, prefix)
+    local last = nil
+    for _ = 1, frames do
+      local o = game.overworld
+      local id = o and o.map and o.map.id
+      if id ~= last then
+        last = id
+        seg(prefix .. ":" .. tostring(id))
+        print(("[bench] %s entered %s at frame %d"):format(prefix, tostring(id),
+                                                           U.frame()))
+      end
+      -- press and RELEASE each frame, the way tests/voxel_perf_probe's seam
+      -- crossing does: a direction left held accumulates in pressQueue and
+      -- the walk stalls where a single tap would have stepped
+      table.insert(game.input.pressQueue, dir)
+      game.input.state[dir] = true
+      coroutine.yield()
+      game.input.state[dir] = false
+    end
+    local o = game.overworld
+    print(("[bench] %s ended on %s at cell (%d,%d)"):format(
+      prefix, tostring(o and o.map and o.map.id),
+      o and o.player and o.player.cellX or -1,
+      o and o.player and o.player.cellY or -1))
+    Perf.setSegment(nil)
+  end
+
+  print("[bench] tag=" .. TAG .. " loadBytes=" .. tostring(loadBytes))
+
+  -- ORDER MATTERS. The cold walk has to be the first time this session
+  -- draws Route 1 and Viridian, so everything before it stays in Pallet
+  -- Town -- a map whose caches the walk does not depend on. Measuring a
+  -- "first entry" into a map an earlier segment already warmed is the one
+  -- way to make this whole benchmark lie.
+
+  -- 1. the flat reference: the game with this mod present but not
+  --    drawing. Every later number is only interesting against this one.
+  U.teleport(game, "PALLET_TOWN", 10, 8, "down")
+  Pipelines.setLevel("voxel", 0)
+  Pipelines.setLevel("tiltshift", 0)
+  settle(90)
+  seg("flat")
+  U.wait(180)
+
+  -- 2. loading in: FULL is what a player picks first and it is the most
+  --    expensive configuration there is (tilt-shift to maximum, 3D
+  --    battles on). Measured from the frame the level changes, so it
+  --    carries the shader compiles, the canvas allocations, the first
+  --    mesh, the first atlas bake and the first glass scan together.
+  settle(60)
+  seg("engage.full")
+  Pipelines.setLevel("voxel", 1)          -- FULL
+  U.wait(240)
+  Perf.setSegment(nil)
+
+  -- 3. the low camera. 75 degrees puts the horizon in frame; the rungs
+  --    below it are the control. Standing still, so what is measured is
+  --    the frame's own cost and not the walk's mesh streaming.
+  for _, rung in ipairs({ 2, 3, 4, 5 }) do   -- 15, 35, 50, 75 degrees
+    Pipelines.setLevel("voxel", rung)
+    settle(60)                                -- let the tween finish
+    seg("pitch:" .. tostring(V.require("VoxelState").ANGLE_LABELS[rung + 1]))
+    U.wait(180)
+    Perf.setSegment(nil)
+  end
+
+  -- 3b. the same low camera at DUSK, which is where the sky costs most:
+  --     the horizon is in frame, so the banded region is at its tallest,
+  --     and the sun is low enough to be in it -- the disc only draws at
+  --     all when it is above the horizon point, so a midday run never
+  --     touches that code and would report it as free.
+  for _, when in ipairs({ "dusk", "night" }) do
+    DayNight.setting:sync(when)
+    settle(60)
+    seg("pitch:75:" .. when)
+    U.wait(180)
+    Perf.setSegment(nil)
+  end
+  DayNight.setting:sync("day")
+  settle(30)
+
+  -- 4/5. arriving somewhere new, at the rung that hurts.
+  --
+  -- Arrival is measured by LOADING each map rather than by walking into
+  -- it. Walking would be more lifelike, but Route 1's ledges make a held
+  -- direction stall against geometry, so a fixed frame count buys a
+  -- different amount of travel on every run -- and a benchmark whose
+  -- route drifts cannot compare two runs at all. A load is the same
+  -- arrival stripped of the travel: the map swaps, and the next frames
+  -- pay for its mesh, its structure analysis, its atlas bake and its
+  -- glass mask exactly as they do behind a door fade.
+  --
+  -- Then the identical list a second time. Every cost in the gap between
+  -- the two passes is a cache that was cold, and that gap IS the
+  -- complaint.
+  Pipelines.setLevel("voxel", 5)             -- 75 degrees
+  local TOUR = { "ROUTE_1", "VIRIDIAN_CITY", "ROUTE_2", "ROUTE_22",
+                 "VIRIDIAN_FOREST", "PEWTER_CITY" }
+  local DWELL = math.max(60, math.floor(HOLD / #TOUR))
+
+  -- Stand in the middle of each map, derived from its own def rather than
+  -- written down: a hardcoded cell that falls outside a map teleports the
+  -- player nowhere and the segment silently measures the previous map.
+  local function centreOf(id)
+    local def = game.data.maps and game.data.maps[id]
+    if not def then return nil end
+    return math.floor(def.width), math.floor(def.height)
+  end
+
+  local function tour(prefix)
+    for _, id in ipairs(TOUR) do
+      local cx, cy = centreOf(id)
+      if cx then
+        U.teleport(game, id, cx, cy, "up")
+        -- the segment opens on the frame AFTER the teleport, so the load
+        -- itself is not charged to the arrival it caused
+        seg(prefix .. ":" .. id)
+        U.wait(DWELL)
+        Perf.setSegment(nil)
+      else
+        print("[bench] skipping unknown map " .. id)
+      end
+    end
+  end
+
+  tour("first")
+  tour("revisit")
+
+  -- 6. streaming while walking: the one crossing that is reliably
+  --    walkable (tests/voxel_perf_probe crosses the same seam) -- Route 1
+  --    south into Pallet, which pulls a neighbour's meshes in mid-stride.
+  U.teleport(game, "ROUTE_1", 10, 34, "down")
+  settle(120)
+  walk("down", 240, "walk")
+
+  -- ---- the report ---------------------------------------------------
+
+  Perf.setSegment(nil)
+  Perf.printReport("bench " .. TAG)
+  Perf.write(TAG, {
+    tag = TAG,
+    loadBytes = loadBytes,
+    hold = HOLD,
+    texturememory = Perf.texturememory or 0,
+    canvases = Perf.canvases or 0,
+    images = Perf.images or 0,
+  })
+  print("[bench] done")
+end

tests/voxel_figure_test.lua

@@ -214,6 +214,172 @@ Structures.buildFigures(twice, map, 0, 3, 8, 11)
 T.eq(#twice.figures, 1,
   "the repaint replaces the pattern, so a rescan cannot match it again")
 
+-- ------- a figure with a DEPTH is an object, not a card
+--
+-- The Marts' cash register: the same authored-mask escape, but a machine
+-- set down on a counter is a box seen from the front rather than a
+-- face-on icon, so it builds as a per-pixel solid.  Driven over a
+-- synthetic copy of the counter's east arm, as all nine maps on the MART
+-- id draw it at cell (1,5):
+--
+--     y=9    16 41      the work surface north of it
+--     y=10   14 15      the register: keypad and receipt curl
+--     y=11   30 31
+--     y=12   16 41      the work surface it stands on
+
+T.check(TileShape.figures("POKECENTER")[1].depth == nil,
+  "the seated man states no depth -- he stays a flat sprite card")
+
+local regs = TileShape.figures("MART")
+T.check(type(regs) == "table" and #regs == 1,
+  "MART carries exactly one figure")
+local reg = regs[1]
+T.eq(reg.w, 2, "the register is two tiles across")
+T.eq(reg.h, 2, "and two tall")
+T.eq(reg.n, 150, "the mask claims 150 pixels of the 256 it spans")
+T.eq(reg.depth, 12, "its body is 12 voxels deep -- three quarters of the cell")
+T.check(reg.thin and reg.thin.rows == 4 and reg.thin.depth == 2,
+  "the four rows above its drawn top edge are 2-voxel paper")
+T.check(reg.flat and reg.flat.x0 == 2 and reg.flat.x1 == 8
+        and reg.flat.r0 == 4 and reg.flat.r1 == 11,
+  "and the keypad is a TOP-VIEW rect, not a face")
+
+local MART_ROWS = { [9] = { 16, 41 }, [10] = { 14, 15 },
+                    [11] = { 30, 31 }, [12] = { 16, 41 } }
+local martS = { shapeAt = {}, tileAt = {}, figures = {}, skip = {},
+                ground = {}, runs = {}, objectQuads = {} }
+for ty, row in pairs(MART_ROWS) do
+  for i, tile in ipairs(row) do
+    martS.tileAt[keyOf(1 + i, ty)] = tile
+    martS.shapeAt[keyOf(1 + i, ty)] = COUNTER
+  end
+end
+local martMap = {
+  tileset = { id = "MART", tilesPerRow = 16,
+              imageWidth = 128, imageHeight = 48 },
+  isWalkableCell = function() return false end,
+}
+Structures.buildFigures(martS, martMap, 2, 3, 9, 12)
+
+T.eq(#martS.figures, 0, "no card was built -- it is a solid")
+T.eq(#martS.objectQuads, 351,
+  "and it landed in the standee channel as 351 quads")
+T.eq(martS.tileAt[keyOf(2, 10)], 16,
+  "its tiles wear the plain work surface now")
+T.eq(martS.tileAt[keyOf(3, 11)], 41, "all four of them")
+T.eq(martS.shapeAt[keyOf(2, 10)].class, "counter",
+  "and keep the counter box the machine stands on")
+
+local rx0, rx1, ry0, ry1, rz0, rz1
+for _, q in ipairs(martS.objectQuads) do
+  for c = 1, 4 do
+    local p = q[c]
+    rx0 = math.min(rx0 or p[1], p[1]); rx1 = math.max(rx1 or p[1], p[1])
+    ry0 = math.min(ry0 or p[2], p[2]); ry1 = math.max(ry1 or p[2], p[2])
+    rz0 = math.min(rz0 or p[3], p[3]); rz1 = math.max(rz1 or p[3], p[3])
+  end
+end
+T.eq(ry0, 8, "it stands ON the counter's 8px top plane, not the floor")
+T.eq(ry1, 24, "and is its drawn 16px tall")
+T.eq(rx0, 18, "west edge at the mask's column 2")
+T.eq(rx1, 30, "east edge at column 13, inside its own cell (16..32)")
+T.eq(rz1, 96, "its FRONT is the cell's own front edge, where it is drawn")
+T.eq(rz0, 84, "and it grows north from there, 4 short of the cell's back")
+
+-- the two thicknesses: the body at 8, the receipt curl at 2, the curl
+-- centred in the body's own band rather than flush with its front
+local bands = {}
+for _, q in ipairs(martS.objectQuads) do
+  for c = 1, 4 do bands[q[c][3]] = true end
+end
+for _, z in ipairs({ 84, 89, 91, 96 }) do
+  T.check(bands[z], "the model has a face at z = " .. z)
+end
+local curl = {}
+for _, q in ipairs(martS.objectQuads) do
+  local lo = math.min(q[1][2], q[2][2], q[3][2], q[4][2])
+  if lo >= 21 then for c = 1, 4 do curl[q[c][3]] = true end end
+end
+T.check(curl[89] and curl[91] and not curl[84] and not curl[96],
+  "clear of the arm's top only the 2-voxel paper band exists")
+
+-- THE L.  The base band (drawn rows 12-15) stands 4 above the counter and
+-- the keypad lies on it as a horizontal plate, so the whole machine is
+-- exactly three surfaces: a foot, an arm, and a deck in the notch.
+local plate, deckTop = {}, 0
+for _, q in ipairs(martS.objectQuads) do
+  local flatQuad = q[1][2] == q[2][2] and q[2][2] == q[3][2]
+                   and q[3][2] == q[4][2]
+  if flatQuad and q[1][2] == 13 then
+    plate[#plate + 1] = q
+  elseif flatQuad and q[1][2] == 12 then
+    deckTop = deckTop + 1
+  end
+end
+T.eq(#plate, 83,
+  "the keypad lies FLAT: one top quad per masked voxel of the deck")
+T.eq(deckTop, 7,
+  "on the base band's own top, which is 4 voxels up (drawn rows 12-15)")
+local dz0, dz1
+for _, q in ipairs(martS.objectQuads) do
+  if q[1][2] == 12 and q[3][2] == 12 then
+    for c = 1, 4 do
+      dz0 = math.min(dz0 or q[c][3], q[c][3])
+      dz1 = math.max(dz1 or q[c][3], q[c][3])
+    end
+  end
+end
+T.eq(dz0, 84, "and that deck runs the body's whole depth")
+T.eq(dz1, 96, "-- plain behind the panel, covered by it in front")
+
+local px0, px1, pz0, pz1
+for _, q in ipairs(plate) do
+  for c = 1, 4 do
+    px0 = math.min(px0 or q[c][1], q[c][1]); px1 = math.max(px1 or q[c][1], q[c][1])
+    pz0 = math.min(pz0 or q[c][3], q[c][3]); pz1 = math.max(pz1 or q[c][3], q[c][3])
+  end
+end
+T.eq(px0, 18, "the deck spans the mask's columns 2..8")
+T.eq(px1, 25, "-- the keypad panel and its own black rim")
+T.eq(pz1, 96, "the deck reaches the body's front edge")
+T.eq(pz0, 84, "and its back -- 8 drawn rows STRETCHED over 12 voxels")
+
+-- the stretch is by whole voxels, centre-sampled: 8 drawn rows over 12
+-- voxels of deck doubles every second one and blurs nothing
+local perRow16, atlasH16 = 16, 48
+local depthRow = {}
+for _, q in ipairs(plate) do
+  local z = math.min(q[1][3], q[2][3], q[3][3], q[4][3])
+  depthRow[z] = math.floor(q.v * atlasH16)
+end
+local seen = {}
+for z = 84, 95 do
+  T.check(depthRow[z] ~= nil, "deck voxel at z = " .. z .. " wears a texel")
+  seen[depthRow[z]] = (seen[depthRow[z]] or 0) + 1
+end
+T.eq(depthRow[95], 11, "the front voxel wears the keypad's own bottom rim")
+T.eq(depthRow[84], 4, "the back one wears its top rim")
+local doubled = 0
+for _, n in pairs(seen) do
+  T.check(n == 1 or n == 2, "no drawn row spreads over more than two voxels")
+  if n == 2 then doubled = doubled + 1 end
+end
+T.eq(doubled, 4, "exactly four of the eight rows double -- 8 into 12")
+
+
+-- and the arm still stands its drawn 8 rows above that deck, carrying
+-- the paper: nothing in the notch reaches higher than the plate
+local armTop, notchTop = 0, 0
+for _, q in ipairs(martS.objectQuads) do
+  for c = 1, 4 do
+    if q[c][1] >= 25 then armTop = math.max(armTop, q[c][2])
+    elseif q[c][1] <= 24 then notchTop = math.max(notchTop, q[c][2]) end
+  end
+end
+T.eq(armTop, 24, "the arm and its receipt curl reach the drawn 16px")
+T.eq(notchTop, 23,
+  "and west of it only the keys (13) and the paper overhanging them")
+
 -- ------- prop_bg: the shades a pinned prop treats as background
 --
 -- The potted plants needed this: their pot's olive base is drawn flush on

tests/voxel_shots_ab.lua

@@ -0,0 +1,346 @@
+-- Driver: the pixel-identity gate for performance work.
+--
+-- Every optimization in this mod's performance pass claims the frame comes
+-- out the same. This driver is what makes that claim checkable rather than
+-- asserted: it renders a fixed set of scenes -- several maps, indoors and
+-- out, at every camera rung, in every display mode -- and writes one PNG
+-- per scene. Run it before a change and after it, hash the two directories,
+-- and any file whose hash moved is a scene the change altered.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/voxel_shots_ab.lua \
+--   SHOT_DIR=<dir> AB_TAG=before lovec.exe .
+--
+-- knobs (env):
+--   SHOT_DIR   output directory (created if missing)   (default "shots/ab")
+--   AB_TAG     subdirectory under SHOT_DIR             (default "before")
+--   AB_MODES   display modes to sweep, comma list      (default all four)
+--
+-- DETERMINISM is the whole game here, because a shot that differs for a
+-- reason other than the change under test makes the gate useless:
+--
+--   * the day/night clock is PINNED (an unpinned sky is a different sky
+--     every second, and it drives the sun angle and the shadow frustum);
+--   * the animated tile slots ride the engine's 60Hz counter, so every
+--     scene is reached after the SAME number of frames from the same
+--     starting state, and the water is at the same point in its roll;
+--   * levels are set through Pipelines.setLevel, never the hotkey, so the
+--     run cannot write the player's options;
+--   * encounters are stubbed off -- a wild battle would replace the scene
+--     the shot is named for.
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+  local OverworldState = require("src.world.OverworldController")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/ab")
+    .. "/" .. (os.getenv("AB_TAG") or "before")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[ab] DRAMATIC_SHAPE mod not loaded -- nothing to compare")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+
+  OverworldState.rollEncounter = function() return nil end
+
+  -- NPCs roam on a random timer (src/world/NPC.lua), and LOVE's RNG is
+  -- seeded differently every launch -- so two runs of this driver put the
+  -- same townsfolk in different places and every shot with a person in it
+  -- differs for a reason that has nothing to do with the change under
+  -- test. Freeze them: `frozen` is the flag the NPC's own update already
+  -- honours, and an NPC mid-step still finishes it, so the settle below
+  -- lands on a still scene. They are still POSED and still drawn, so the
+  -- billboard, its lean and its shadow are all still under test.
+  local NPC = require("src.world.NPC")
+  if not NPC.dramaticShapeAbFreeze then
+    local inner = NPC.update
+    function NPC:update(...)
+      self.frozen = true
+      return inner(self, ...)
+    end
+    NPC.dramaticShapeAbFreeze = true
+  end
+  pcall(love.math.setRandomSeed, 20260730)
+
+  -- Freeze the tile-animation clock, on BOTH routes to it.
+  --
+  -- TileRenderer.tick consumes WALL-CLOCK dt (so the water rolls at the
+  -- same speed on a 60Hz and a 144Hz panel), which means the step a shot
+  -- catches depends on how fast the machine got there rather than on
+  -- anything the run did. Stubbing tick pins the counter the flat tile
+  -- layer reads.
+  --
+  -- The mod reads the SAME counter but through its own chain
+  -- (TerrainAtlas.animFrame): TileRenderer.animFrame if the build exports
+  -- one, else the local off tick's upvalues, else -- and this is the trap
+  -- -- wall-clock time. A stubbed tick has no upvalues, so stubbing it
+  -- ALONE knocks the mod onto the wall-clock fallback and makes the
+  -- flowers drift between two otherwise identical runs. Exporting a
+  -- constant animFrame takes the first branch and pins that route too.
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+
+  -- The scenes. Chosen for what each one can BREAK, not for looks:
+  --   ROUTE_1          open ground, grass billboards, a long view north --
+  --                    the case a shadow-frustum or culling change moves
+  --   VIRIDIAN_CITY    buildings, window panes (the glass mask), signs
+  --   PALLET_TOWN      the seam with Route 1: neighbour meshes and ring
+  --   VIRIDIAN_FOREST  dense round-tree hulls, heavy occlusion
+  --   REDS_HOUSE_1F    indoors: no sky, no sun, authored figures
+  --   PEWTER_CITY      a second tileset with its own atlas bake
+  local SCENES = {
+    { id = "ROUTE_1", x = 10, y = 20, face = "up", label = "open" },
+    { id = "VIRIDIAN_CITY", x = 20, y = 26, face = "up", label = "town" },
+    { id = "PALLET_TOWN", x = 10, y = 2, face = "up", label = "seam" },
+    { id = "VIRIDIAN_FOREST", x = 16, y = 24, face = "up", label = "trees" },
+    { id = "REDS_HOUSE_1F", x = 4, y = 4, face = "up", label = "indoor" },
+    { id = "PEWTER_CITY", x = 16, y = 20, face = "down", label = "pewter" },
+  }
+
+  -- OFF is in the list deliberately: a change that speeds the 3D path up
+  -- must not have touched the flat one either. Then the three camera
+  -- rungs, 75 last because it is the low camera this performance work is
+  -- aimed at.
+  --
+  -- FULL (rung 1) is NOT here, and cannot usefully be. It is a settings
+  -- PRESET, not a render path: it sets tilt-shift to maximum, flattens the
+  -- world curve, fits the zoom, switches 3D battles on -- and pins DAYTIME
+  -- to SYNC and HOLDS it there (main.lua's applyFull / DayNight.forceSync),
+  -- which overrides this driver's pinned clock and makes every shot after
+  -- it depend on the wall clock. It also persists all of that, so one run's
+  -- FULL changes the options the NEXT run starts from. What FULL renders is
+  -- 35 degrees with the blur at 3, which rung 3 plus AB_TSHIFT=3 covers
+  -- exactly.
+  local RUNGS = {}
+  for n in (os.getenv("AB_RUNGS") or "0,2,3,5"):gmatch("%d+") do
+    RUNGS[#RUNGS + 1] = tonumber(n)
+  end
+
+  local TSHIFT = math.floor(tonumber(os.getenv("AB_TSHIFT")) or 0)
+
+  -- AB_SHADOW=0 renders with the sun pass's contribution turned off
+  -- (SHADOW_ALPHA 0 short-circuits the lookup in the scene shader). A
+  -- bisection tool: when a set of shots will not reproduce, this says
+  -- whether what is moving is in the shadow map or somewhere else.
+  if os.getenv("AB_SHADOW") == "0" then
+    V.require("Voxel3D").SHADOW_ALPHA = 0
+  end
+
+  -- PaletteFX.MODES, minus the inverted novelties: `ogred` and `classic`
+  -- are the SGB paths this mod bakes an atlas for, `gbc` is the shared
+  -- default, and `redpp` is the one that rebakes an atlas PER MAP -- four
+  -- genuinely different routes through TerrainAtlas.
+  local MODES = {}
+  for m in (os.getenv("AB_MODES") or "ogred,classic,gbc,redpp"):gmatch("[^,]+") do
+    MODES[#MODES + 1] = m
+  end
+
+  -- Two times of day, because half the shader only runs in one of them:
+  -- the window lamps, the moon disc and the night tint are all dark-only,
+  -- and the glint sweep and the sun disc are day-only.
+  local TIMES = { "day", "night" }
+
+  local shots, missed = 0, 0
+
+  -- U.shot's own mkdir is the POSIX one, which cmd.exe does not
+  -- understand, and a missing directory makes every capture vanish
+  -- silently. Try both spellings once, up front.
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  -- A capture that always costs the SAME number of frames.
+  --
+  -- U.shot spins up to 120 frames waiting for the capture to land, which
+  -- is right for a screenshot and wrong for this: the animated tile slots
+  -- (water rolling, flowers opening) ride the engine's frames-since-boot
+  -- counter, so a scene reached after a different number of frames renders
+  -- its water at a different point in the roll and the shot differs for a
+  -- reason no change caused. A driver resume and a rendered frame are 1:1
+  -- here, so the capture lands on the next draw and a fixed budget is both
+  -- enough and constant.
+  local CAPTURE_FRAMES = 4
+
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+  local ShadowMap = V.require("ShadowMap")
+
+  -- Wait for the scene to actually BE the scene the shot is named for.
+  -- Two things are still in motion after a teleport, and both are timed in
+  -- wall-clock seconds rather than frames, so "wait N frames" settles them
+  -- by a different amount on every machine and every run:
+  --
+  --   the build queue -- meshes are built on a per-frame time budget, so a
+  --   slower run captures a half-built neighbour;
+  --   the camera tween -- Voxel.t runs on dt over TWEEN_TIME, so a shot
+  --     taken before it lands is at some arbitrary intermediate pitch.
+  --
+  -- Both are waited on by their own completion flag, then a short fixed
+  -- settle. The variable wait is harmless now that the animation clock is
+  -- frozen above -- otherwise it would move the water instead.
+  -- and the CAMERA, which is the subtle one. It eases toward the player
+  -- over wall-clock dt, so after a fixed wait it has covered a distance
+  -- that depends on how fast the machine ran -- and the sun pass is only
+  -- redrawn when the camera crosses a quarter-world-pixel (VoxelScene's
+  -- shadow signature), so a frame caught mid-ease carries a shadow map
+  -- fitted for a slightly different camera than the one it is drawn with.
+  -- That is a real and deliberate tolerance in the mod, but it makes the
+  -- gate compare two arbitrary points inside it. Waiting for the camera
+  -- to stop moving entirely puts every shot at the same steady state.
+  local function cameraStill()
+    local o = game.overworld
+    local c = o and o.camera
+    if not c then return true end
+    local lx, ly, held = nil, nil, 0
+    for _ = 1, 300 do
+      if c.x == lx and c.y == ly then
+        held = held + 1
+        if held >= 10 then return true end
+      else
+        held = 0
+        lx, ly = c.x, c.y
+      end
+      U.wait(1)
+    end
+    return false
+  end
+
+  local function settleBuild()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    cameraStill()
+    -- and then force one final sun pass at the settled camera. The map is
+    -- only redrawn when the camera crosses a quarter world pixel, so a
+    -- still camera holds whatever was drawn at the moment it last did --
+    -- correct to within that tolerance, but fitted from a position that
+    -- depends on where the easing happened to be, which differs by a few
+    -- hundredths of a pixel between runs and moves every shadow edge by a
+    -- shade or two. Forgetting the stamp redraws from the state the shot
+    -- is actually taken in, and two runs then agree exactly.
+    -- guarded so this driver can also be pointed at a build that predates
+    -- the seam, which is exactly what capturing a "before" reference means
+    if ShadowMap.forget then ShadowMap.forget() end
+    U.wait(20)
+  end
+
+  -- AB_TRACE=1 prints the state each shot was taken in. When two runs of
+  -- this driver disagree, this is what says which input moved.
+  local TRACE = os.getenv("AB_TRACE") == "1"
+
+  local function trace(name)
+    if not TRACE then return end
+    local o = game.overworld
+    local e = ShadowMap.extent or {}
+    print(("[ab] %-28s cam=(%.4f,%.4f) player=(%.3f,%.3f) res=%d extent=(%.3f,%.3f,%.3f) KX=%.6f KZ=%.6f angle=%.6f pend=%d")
+      :format(name,
+              o and o.camera and o.camera.x or -1,
+              o and o.camera and o.camera.y or -1,
+              o and o.player and o.player.px or -1,
+              o and o.player and o.player.py or -1,
+              ShadowMap.res or 0,
+              e[1] or 0, e[2] or 0, e[3] or 0,
+              ShadowMap.KX or 0, ShadowMap.KZ or 0,
+              Voxel.angle or 0,
+              ChunkMesher.pending()))
+  end
+
+  -- AB_SHADOWDUMP=1 also writes the packed depth map itself, into the save
+  -- directory. When the scene differs but every input to the sun pass is
+  -- identical, the map is the only place left to look.
+  local DUMP = os.getenv("AB_SHADOWDUMP") == "1"
+
+  local function dumpShadow(name)
+    if not DUMP then return end
+    local tex = ShadowMap.texture()
+    if not (tex and tex.newImageData) then return end
+    pcall(function()
+      love.filesystem.createDirectory("ab_shadow")
+      tex:newImageData():encode("png", "ab_shadow/" .. name .. ".png")
+    end)
+  end
+
+  local function capture(name)
+    trace(name)
+    dumpShadow(name)
+    local path = ("%s/%s.png"):format(ROOT, name)
+    game.capturePath = path
+    U.wait(CAPTURE_FRAMES)
+    local f = io.open(path, "rb")
+    if f then
+      f:close()
+      shots = shots + 1
+    else
+      missed = missed + 1
+      print("[ab] capture did not reach disk: " .. path)
+    end
+  end
+
+  local PaletteFX = require("src.render.PaletteFX")
+
+  local function setMode(mode)
+    local known = false
+    for _, m in ipairs(PaletteFX.MODES) do
+      if m == mode then known = true break end
+    end
+    if not known then return false end
+    return (pcall(PaletteFX.setMode, mode))
+  end
+
+  -- A fixed zoom, so the view size every shot is composed at is the same
+  -- one. Zoom is persisted, so without this a session that ever ran the
+  -- FULL preset (which fits the zoom to the window) leaves a different
+  -- view size behind for every later run.
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  for _, mode in ipairs(MODES) do
+    if setMode(mode) then
+      for _, when in ipairs(TIMES) do
+        DayNight.setting:sync(when)
+        for _, s in ipairs(SCENES) do
+          for _, rung in ipairs(RUNGS) do
+            U.teleport(game, s.id, s.x, s.y, s.face)
+            Pipelines.setLevel("voxel", rung)
+            -- pinned AFTER the voxel rung, because FULL is a preset that
+            -- reaches over and sets this row itself (main.lua's applyFull)
+            -- and persists it -- so without this, one run's FULL leaks a
+            -- blur level into the NEXT run's options.lua and every shot
+            -- differs for a reason no code change caused. Sharp by
+            -- default: a gaussian smears a one-pixel geometry difference
+            -- across the whole frame, which is exactly what a gate meant
+            -- to localise differences must not do. AB_TSHIFT=3 runs the
+            -- blur path deliberately.
+            Pipelines.setLevel("tiltshift", TSHIFT)
+            -- Wait for the build queue to drain rather than for a fixed
+            -- number of frames. Meshes are built on a per-frame time
+            -- budget, so how much of a map exists after N frames is a
+            -- property of the MACHINE -- a slower run captures a
+            -- half-built neighbour and the shot differs for no reason the
+            -- change caused. Draining first, then settling a fixed 40
+            -- frames for the camera tween, makes the scene the same
+            -- scene everywhere. (Safe now that the animation clock above
+            -- is frozen: a variable wait no longer moves the water.)
+            settleBuild()
+            capture(("%s_%s_%s_v%d"):format(mode, when, s.label, rung))
+          end
+        end
+      end
+    else
+      print("[ab] display mode " .. mode .. " unavailable, skipped")
+    end
+  end
+
+  print(("[ab] %d shots into %s (%d failed to reach disk)")
+    :format(shots, ROOT, missed))
+end

tests/vr_probe.lua

@@ -0,0 +1,61 @@
+-- Scratch driver: exercise the VR stack against the real machine -- the
+-- FFI cdefs compile, the loader DLL loads, LOVE's GL context and canvas
+-- framebuffers are discoverable, and the OpenXR instance either comes up
+-- (headset present) or reports exactly why not (no runtime / no HMD).
+-- With a headset connected and the runtime up, it holds a VR session open
+-- for ten seconds of frames: diorama first, then the 1ST rung.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/vr_probe.lua \
+--   lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[vr] DRAMATIC_SHAPE mod not loaded")
+    return love.event.quit()
+  end
+  local V = handle.lib
+  local VR = V.require("VR")
+  local VRGL = V.require("VRGL")
+  local Voxel = V.require("VoxelState")
+
+  U.teleport(game, "PALLET_TOWN", 10, 12, "down")
+  Pipelines.setLevel("voxel", 2)
+  U.wait(30)
+
+  -- the GL floor the whole thing stands on
+  local okGL = VRGL.load()
+  print("[vr] GL interop: " .. tostring(okGL) .. " -- " .. VRGL.status())
+  local hdc, hglrc = VRGL.contexts()
+  print("[vr] wgl contexts: " .. tostring(hdc) .. " / " .. tostring(hglrc))
+  local okC, c = pcall(love.graphics.newCanvas, 64, 64)
+  if okC then
+    print("[vr] canvas FBO discovery: " .. tostring(VRGL.canvasFBO(c)))
+  end
+
+  -- the OpenXR stack, driven by the same row the player would use
+  VR.setting:sync(true)
+  for _ = 1, 300 do
+    U.wait(1)
+    if VR.active() or VR.status():find("XR_ERROR") then break end
+  end
+  print("[vr] status: " .. VR.status())
+  print("[vr] active: " .. tostring(VR.active()))
+
+  if VR.active() then
+    print("[vr] holding a diorama session for ~5s of frames")
+    U.wait(450)
+    print("[vr] switching to 1ST for ~5s of frames")
+    Pipelines.setLevel("voxel", Voxel.FP_LEVEL)
+    U.wait(450)
+    print("[vr] still active: " .. tostring(VR.active())
+          .. " -- " .. VR.status())
+  end
+
+  VR.setting:sync(false)
+  U.wait(10)
+  print("[vr] after toggle off: " .. VR.status())
+  love.event.quit()
+end

tests/water_curve_shots.lua

@@ -0,0 +1,121 @@
+-- Scratch driver: water shot with V-CURVE walked OFF..3, to see what the
+-- world bend does to the reflective pass.
+--
+--   POKEPORT_DRIVER=mods/DramaticShapeVoxelMod/tests/water_curve_shots.lua \
+--   SHOT_DIR=.scratchpad/watercurve AB_TAG=before lovec.exe .
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local ROOT = (os.getenv("SHOT_DIR") or "shots/watercurve")
+    .. "/" .. (os.getenv("AB_TAG") or "after")
+
+  local handle = game.mods.exports["DRAMATIC_SHAPE"]
+  if not (handle and handle.lib) then
+    print("[water] DRAMATIC_SHAPE mod not loaded")
+    return
+  end
+  local V = handle.lib
+  local DayNight = V.require("DayNight")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Voxel = V.require("VoxelState")
+  local WorldCurve = V.require("WorldCurve")
+  local Water = V.require("Water")
+  -- WATER_RUNG=sky drops the screen-space march and leaves the sky path, to
+  -- tell an artefact of the one from an artefact of the other
+  if os.getenv("WATER_RUNG") then Water.setting:sync(os.getenv("WATER_RUNG")) end
+
+  require("src.world.OverworldController").rollEncounter = function() return nil end
+  local TileRenderer = require("src.render.TileRenderer")
+  TileRenderer.tick = function() end
+  TileRenderer.animFrame = function() return 0 end
+  DayNight.setting:sync(os.getenv("WATER_TIME") or "night")
+
+  pcall(os.execute, 'mkdir -p "' .. ROOT .. '" 2>/dev/null')
+  pcall(os.execute, 'mkdir "' .. ROOT:gsub("/", "\\") .. '" 2>nul')
+
+  local Zoom = require("src.render.Zoom")
+  pcall(function()
+    game.save.options.zoom = 1
+    Zoom.applyOptions(game.save.options)
+  end)
+
+  local function settle()
+    for _ = 1, 900 do
+      if ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    for _ = 1, 300 do
+      if Voxel.t >= 1 and Voxel.ready and ChunkMesher.pending() == 0 then break end
+      U.wait(1)
+    end
+    U.wait(40)
+  end
+
+  -- Stand on the walkable cell just north of the widest run of water on the
+  -- map, so a scene is picked by where the water actually is rather than by
+  -- a coordinate guessed off the block list.
+  local TileShape = V.require("TileShape")
+  local function shore(map)
+    local def = map.def
+    local shapes = TileShape.forMap(map)
+    local function classAt(cx, cy)
+      local tx, ty = cx * 2, cy * 2
+      local s = TileShape.at(map, shapes, map:tileAt(tx, ty), tx, ty)
+      return s and s.class
+    end
+    local best, bestRun = nil, 0
+    for cy = 1, def.height * 2 - 1 do
+      local run, start = 0, nil
+      for cx = 0, def.width * 2 - 1 do
+        if classAt(cx, cy) == "water" then
+          start = start or cx
+          run = run + 1
+          if run > bestRun and classAt(cx, cy - 1) ~= "water" then
+            bestRun, best = run, { x = start + math.floor(run / 2), y = cy - 1 }
+          end
+        else
+          run, start = 0, nil
+        end
+      end
+    end
+    return best
+  end
+
+  local SCENES = {
+    { map = "PALLET_TOWN",     label = "pallet" },
+    { map = "CERULEAN_CITY",   label = "cerulean" },
+    { map = "VERMILION_CITY",  x = 18, y = 27, label = "vermilion" },
+    { map = "ROUTE_24",        label = "route24" },
+    { map = "VIRIDIAN_CITY",   label = "viridian" },
+  }
+
+  local shots = 0
+  for _, s in ipairs(SCENES) do
+    if not s.x then
+      -- teleport once so the map is loaded, then let the scan place us
+      U.teleport(game, s.map, 1, 1, "down")
+      U.wait(4)
+      local spot = game.overworld and game.overworld.map and shore(game.overworld.map)
+      if spot then s.x, s.y = spot.x, spot.y else s.x, s.y = 1, 1 end
+      print(("[water] %s shore at (%d,%d)"):format(s.label, s.x, s.y))
+    end
+    for _, rung in ipairs({ 3, 4 }) do
+      for _, curve in ipairs({ 0, 3 }) do
+        U.teleport(game, s.map, s.x, s.y, s.face or "down")
+        Pipelines.setLevel("voxel", rung)
+        Pipelines.setLevel("tiltshift", 0)
+        WorldCurve.setting:setIndex(curve + 1, game)
+        settle()
+        local path = ("%s/%s_v%d_c%d.png"):format(ROOT, s.label, rung, curve)
+        game.capturePath = path
+        U.wait(8)
+        local f = io.open(path, "rb")
+        if f then f:close() shots = shots + 1
+        else print("[water] capture missed: " .. path) end
+      end
+    end
+  end
+  print(("[water] %d shots into %s"):format(shots, ROOT))
+  love.event.quit()
+end

tests/water_reflect_probe.lua

@@ -0,0 +1,128 @@
+-- Driver: WHY is the water not reflecting anything?
+--
+-- The reflective pass has several links and every one of them fails quietly
+-- back to flat water, which looks exactly like the row being off. This walks
+-- the chain in the LIVE game and prints where it stops.
+--
+--   POKEPORT_DRIVER=mods/DRAMATIC_SHAPE/tests/water_reflect_probe.lua lovec .
+--
+-- knobs (env):
+--   REFL_MAP    map id                       (default PALLET_TOWN)
+--   REFL_SPOT   "x,y[,facing]"               (default 5,6,down)
+--   REFL_LEVEL  voxel rung                   (default 5, the 75-degree camera,
+--                                             which is where a reflection is
+--                                             most of what you can see)
+--   REFL_TIME   daytime pin (day/dusk/...)   (default: leave as-is)
+return function(game)
+  local U = dofile("tests/drivers/util.lua")
+  local Pipelines = require("src.render.Pipelines")
+
+  local mapId = os.getenv("REFL_MAP") or "PALLET_TOWN"
+  local level = math.floor(tonumber(os.getenv("REFL_LEVEL")) or 5)
+  local sx, sy, facing = (os.getenv("REFL_SPOT") or "5,6,down")
+    :match("^%s*(%d+)%s*,%s*(%d+)%s*,?%s*(%a*)")
+  facing = (facing ~= "" and facing) or "down"
+
+  local function say(...) print("[water-ssr] " .. string.format(...)) end
+
+  U.teleport(game, mapId, tonumber(sx), tonumber(sy), facing)
+  U.wait(20)
+  Pipelines.setLevel("voxel", level)
+  U.wait(40)                       -- outlast the camera tween and the build
+
+  local V = game.mods.exports["DRAMATIC_SHAPE"]
+  V = V and V.lib
+  if not V then return say("mod exports unreachable -- is it enabled?") end
+
+  local Water = V.require("Water")
+  local Voxel3D = V.require("Voxel3D")
+  local ChunkMesher = V.require("ChunkMesher")
+  local Sky = V.require("Sky")
+  local DayNight = V.require("DayNight")
+
+  if os.getenv("REFL_TIME") then
+    DayNight.setting:sync(os.getenv("REFL_TIME"))
+    U.wait(5)
+  end
+
+  local ow = game.overworld
+  local map = ow and ow.map
+  if not map then return say("no live map") end
+
+  -- 1. is the row on at all?
+  say("row=%s level=%d", tostring(Water.setting:get()), Water.level())
+  if not Water.enabled() then
+    return say("STOP: WATER is OFF -- press 9, or set the row")
+  end
+
+  -- 2. is there any water on this map to reflect in?
+  local terrain, water = ChunkMesher.pair(map, false)
+  if not terrain then terrain, water = ChunkMesher.pair(map, true) end
+  say("terrain mesh=%s water mesh=%s", tostring(terrain ~= nil),
+      tostring(water ~= nil))
+  if not terrain then
+    return say("STOP: no terrain mesh yet -- the build is still cooking")
+  end
+  if not water then
+    say("STOP: this map has no water surface. That is not a fault unless")
+    say("      you can see a lake: check the tileset's water tiles reach")
+    say("      TileShape (run voxel_survey.lua for the shape breakdown).")
+    return
+  end
+
+  -- 3. did the driver give us a depth texture to read? This is the one
+  --    hardware requirement the rest of the mode does not already have.
+  say("depth canvas readable: %s", tostring(Voxel3D.depthReadable()))
+  if not Voxel3D.depthReadable() then
+    say("STOP: no readable depth canvas on this driver (tried depth24, ")
+    say("      depth24stencil8, depth32f and depth16).")
+    say("      The water falls back to the flat scene shader, which is")
+    say("      exactly what it looked like before this feature existed.")
+    return
+  end
+
+  -- 4. did the shader build? Both variants -- the wireframe one needs
+  --    derivatives, which a driver may refuse on its own.
+  say("shader plain=%s grid=%s",
+      tostring(Water.shader(false) ~= nil), tostring(Water.shader(true) ~= nil))
+  if not Water.shader(false) then
+    return say("STOP: the water shader did not compile -- the mod log has "
+               .. "the driver's own message")
+  end
+
+  -- 5. is there a sky to reflect, and something hanging in it?
+  local ramp, count = Sky.ramp()
+  say("sky ramp=%s bands=%s edge=%s", tostring(ramp ~= nil), tostring(count),
+      tostring(Voxel3D.skyEdge))
+  local body = DayNight.body()
+  if body then
+    local amt = DayNight.glow()
+    local w, h = Voxel3D.size()
+    local rpx = Sky.discRadius(h, Voxel3D.cell or 1,
+                               { moon = body.moon, glowAmt = amt })
+    local ang = rpx / ((h or 1) / math.max(1e-4, Voxel3D.fovY or 1))
+    say("body=%s dir=(%.2f, %.2f, %.2f) disc=%.1fpx (%.2f deg)",
+        body.moon and "moon" or "sun", body.dx, body.dy, body.dz, rpx,
+        math.deg(ang))
+  else
+    say("body: none in the sky right now (set REFL_TIME=day or =night)")
+  end
+  if not ramp then
+    say("NOTE: no band ramp -- indoors, or the ramp could not be built. The")
+    say("      sky half of the reflection is off; the ray march still runs.")
+  end
+
+  -- 6. how much reflection this camera is actually asking for. Both numbers
+  --    fall out of the rung, and between them they explain every "it only
+  --    works at 75" report: Fresnel decides how much shows, and the lean
+  --    decides whether what shows has anything in it.
+  local f = Water.FRESNEL_FLOOR + (Water.FRESNEL_CEIL - Water.FRESNEL_FLOOR)
+            * (1 - Voxel3D.descent) ^ Water.FRESNEL_POWER
+  say("camera: descent %.3f -> fresnel about %.2f, horizon lean %.2f",
+      Voxel3D.descent, f, Water.lean(Voxel3D.descent))
+  say("waves: %d px columns, phase %.2f", Water.WAVE_HEIGHT, Water._waveTime())
+
+  say("OK: every link is live. The effect is strongest at REFL_LEVEL=5 (the")
+  say("    75-degree rung, where Fresnel is highest and the reflection is")
+  say("    exact) and with a low sun (REFL_TIME=dusk).")
+end