CLOSES #1603

src/core/Game.lua

@@ -1260,6 +1260,7 @@ function Game:applyOptions(opts)
   -- after VideoMode: a faithful-resolution lock is an exact window size, so
   -- it has to be the last word on the window (it drops fullscreen to hold)
   require("src.core.FaithfulRes").applyOptions(opts)
+  require("src.core.ScreenPosition").applyOptions(opts)
   -- normalizes a nil/garbage cap to the 60 default, so old saves with no
   -- fpsCap key pace at the standard rate (issue #88)
   require("src.core.FrameCap").applyOptions(opts)

src/core/Game2.lua

@@ -1660,8 +1660,9 @@ function Game2:drawScene(w, h)
       -- row to opt into the step-down half, so CENTERED is the whole rule
       -- here.
       local s = self.world:fitScale()
+      local ox, oy = Chrome.fitOrigin(w, h, s)
       G.push()
-      G.translate(math.floor((w - 160 * s) / 2), math.floor((h - 144 * s) / 2))
+      G.translate(ox, oy)
       G.scale(s, s)
       self.stack:draw()
       G.pop()
@@ -1982,6 +1983,7 @@ function Game2:applyOptions()
     haptics = options.haptics,
   })
   require("src.core.VideoMode").applyOptions(options)
+  require("src.core.ScreenPosition").applyOptions(options)
   require("src.core.FrameCap").applyOptions(options)
   require("src.world.gen2.BorderFill").applyOptions(options)
   local GBCFX = require("src.render.GBCFX")

src/core/SaveData.lua

@@ -285,6 +285,7 @@ function SaveData.defaultOptions()
     -- lock the window to an exact 160x144 multiple, 1..4 (0 = OFF); see
     -- src/core/FaithfulRes.lua.  Ignored on mobile.
     faithfulRes = 0,
+    screenPos = "center",
     -- hard render frame-rate cap; render-only pacing (issue #88, FrameCap.lua)
     fpsCap = 60,
     -- graphics performance tier: auto | high | balanced | low.  "auto"

src/core/ScreenPosition.lua

@@ -0,0 +1,66 @@
+local ScreenPosition = {}
+
+ScreenPosition.MODES = { "center", "upper", "top" }
+ScreenPosition.DEFAULT = "center"
+ScreenPosition.mode = ScreenPosition.DEFAULT
+
+local LABELS = { center = "CENTER", upper = "UPPER", top = "TOP" }
+
+function ScreenPosition.normalize(v)
+  if LABELS[v] then return v end
+  return ScreenPosition.DEFAULT
+end
+
+function ScreenPosition.label(v)
+  return LABELS[ScreenPosition.normalize(v)]
+end
+
+function ScreenPosition.cycle(v, dir)
+  v = ScreenPosition.normalize(v)
+  local modes = ScreenPosition.MODES
+  local cur = 1
+  for i, mode in ipairs(modes) do
+    if mode == v then cur = i break end
+  end
+  return modes[(cur - 1 + (dir or 1)) % #modes + 1]
+end
+
+function ScreenPosition.setMode(v)
+  ScreenPosition.mode = ScreenPosition.normalize(v)
+end
+
+function ScreenPosition.applyOptions(opts)
+  ScreenPosition.setMode(opts and opts.screenPos)
+end
+
+function ScreenPosition.safeTop()
+  local ok, SafeArea = pcall(require, "src.core.SafeArea")
+  if not ok then return 0 end
+  local okr, _, y = pcall(SafeArea.rect)
+  if not okr then return 0 end
+  return math.max(0, tonumber(y) or 0)
+end
+
+function ScreenPosition.skinActive(w, h)
+  local ok, TouchSkin = pcall(require, "src.core.TouchSkin")
+  if not ok or type(TouchSkin.viewport) ~= "function" then return false end
+  local okv, x = pcall(TouchSkin.viewport, w, h)
+  return okv and x ~= nil
+end
+
+function ScreenPosition.lift(viewH, contentH, safeTop)
+  if ScreenPosition.mode == "center" then return 0 end
+  viewH = tonumber(viewH) or 0
+  contentH = tonumber(contentH) or 0
+  local slack = viewH - contentH
+  if slack <= 0 then return 0 end
+  local centered = math.floor(slack / 2)
+  local target = ScreenPosition.mode == "top" and 0 or math.floor(slack / 4)
+  safeTop = math.floor(tonumber(safeTop) or 0)
+  if safeTop > 0 and target < safeTop then
+    target = math.min(safeTop, centered)
+  end
+  return centered - target
+end
+
+return ScreenPosition

src/core/gen2/Save.lua

@@ -288,6 +288,7 @@ Save.DEFAULT_OPTIONS = {
   musicFilter = 0,          -- low-pass steps, 0 = off
   haptics = "light",
   touchControls = { enabled = true },
+  screenPos = "center",
 }
 
 function Save.defaultOptions()
@@ -308,7 +309,7 @@ end
 Save.OPTIONS_KEY = "gold"
 
 local SHARED_KEYS = {
-  touchControls = true, haptics = true,
+  touchControls = true, haptics = true, screenPos = true,
   mods = true, modsByVersion = true, modsGen2 = true,
   modOptions = true, modProfiles = true, modProfilesSeeded = true,
   activeProfile = true,