Pixel-sized canvases: dpiscale 1 on every framebuffer allocation

lib/AntiAlias.lua

@@ -133,7 +133,10 @@ 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)
+    -- dpiscale 1: `w`/`h` are the pass's DISPLAY size in pixels, and the
+    -- highdpi default would fold the supersample down into a target that
+    -- is itself density x too big (see Voxel3D.newDepth for the trap)
+    local ok, c = pcall(love.graphics.newCanvas, w, h, { dpiscale = 1 })
     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

lib/BattleDOF.lua

@@ -98,9 +98,10 @@ end
 -- would reallocate both every time a battle started or ended.
 local function getCanvases(w, h)
   if not ping or cw ~= w or ch ~= h then
-    local ok, a = pcall(love.graphics.newCanvas, w, h)
+    -- dpiscale 1: pixel-sized buffers, like TiltShift's (see Voxel3D.newDepth)
+    local ok, a = pcall(love.graphics.newCanvas, w, h, { dpiscale = 1 })
     if not ok then return nil end
-    local okB, b = pcall(love.graphics.newCanvas, w, h)
+    local okB, b = pcall(love.graphics.newCanvas, w, h, { dpiscale = 1 })
     if not okB then return nil end
     -- the gaussian's fractional tap offsets need linear filtering
     a:setFilter("linear", "linear")

lib/BattleHud.lua

@@ -79,7 +79,8 @@ local function getShader()
 end
 
 local function canvasOf(w, h, filter)
-  local ok, c = pcall(love.graphics.newCanvas, w, h)
+  -- dpiscale 1: pixel-sized buffers (see Voxel3D.newDepth for the trap)
+  local ok, c = pcall(love.graphics.newCanvas, w, h, { dpiscale = 1 })
   if not ok then return nil end
   c:setFilter(filter or "linear", filter or "linear")
   return c

lib/ShadowMap.lua

@@ -186,7 +186,11 @@ end
 local function getCanvas(res)
   if canvas == false then return nil end
   if canvas and canvasRes == res then return canvas end
-  local ok, c = pcall(love.graphics.newCanvas, res, res)
+  -- dpiscale 1: `res` is the map's edge in TEXELS, and a highdpi default
+  -- would cube the memory for texels the filter never asks for (see
+  -- Voxel3D.newDepth) -- sunTexel = 1/res in the main pass assumes the
+  -- stored map is exactly res texels across
+  local ok, c = pcall(love.graphics.newCanvas, res, res, { dpiscale = 1 })
   if not (ok and c) then
     canvas = false
     return nil

lib/TiltShift.lua

@@ -85,9 +85,12 @@ end
 
 local function getCanvases(w, h)
   if not ping or cw ~= w or ch ~= h then
-    local ok, a = pcall(love.graphics.newCanvas, w, h)
+    -- dpiscale 1: `w`/`h` came off the input canvas in pixels, and a
+    -- highdpi default would multiply by the display density again (see
+    -- Voxel3D.newDepth) -- two gaussian passes at 9x the pixels
+    local ok, a = pcall(love.graphics.newCanvas, w, h, { dpiscale = 1 })
     if not ok then return nil end
-    local okB, b = pcall(love.graphics.newCanvas, w, h)
+    local okB, b = pcall(love.graphics.newCanvas, w, h, { dpiscale = 1 })
     if not okB then return nil end
     -- the gaussian's fractional tap offsets need linear filtering
     a:setFilter("linear", "linear")

lib/Voxel3D.lua

@@ -308,8 +308,15 @@ 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
+    -- dpiscale 1: `w`/`h` are already PIXELS. Left to default, a highdpi
+    -- surface (iOS, Android -- see conf.lua) multiplies the canvas by the
+    -- display density AGAIN -- the same trap TerrainAtlas and BattlePics
+    -- already step around -- and a nominally window-sized buffer comes out
+    -- density^2 the screen's area (9x at 3x). Everywhere a canvas here is
+    -- sized from pixel dimensions gets the same option, so no pair of them
+    -- can disagree about what a coordinate means.
     local ok, made = pcall(love.graphics.newCanvas, w, h,
-                           { format = format, readable = true })
+                           { format = format, readable = true, dpiscale = 1 })
     if ok and made then c = made break end
   end
   if not c then return nil end
@@ -640,7 +647,8 @@ function Voxel3D.beginScene(w, h, cx, cy, vw, vh, sky, slot)
   local name = slot or "world"
   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)
+    -- dpiscale 1, like the depth canvas (see newDepth for the why)
+    local ok, c = pcall(love.graphics.newCanvas, w, h, { dpiscale = 1 })
     if not ok then return false end
     c:setFilter("nearest", "nearest")
     if slotHeld then releaseSlot(slotHeld) end
@@ -876,7 +884,9 @@ end
 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)
+    -- dpiscale 1, like the scene canvas it mirrors (see newDepth)
+    local ok, c = pcall(love.graphics.newCanvas, held.w, held.h,
+                        { dpiscale = 1 })
     if not (ok and c) then return nil end
     pcall(c.setFilter, c, "nearest", "nearest")
     pcall(c.setWrap, c, "clamp", "clamp")