DramaticShapeVoxelMod/tests/water_reflect_probe.lua

-- 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 (depth24/readable).")
    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