Use 1x TTF rasterizer on Android

src/render/Font.lua

@@ -137,8 +137,10 @@ function Font.load(data)
   -- typo'd path degrades exactly like a missing page image does above.
   if type(def.ttf) == "table" then
     local file = def.ttf.file or Font.PLAINPIXEL
-    local ok, obj = pcall(love.graphics.newFont, file,
-                          def.ttf.size or Font.PLAINPIXEL_SIZE, "mono")
+    local size = def.ttf.size or Font.PLAINPIXEL_SIZE
+    -- The game renders into a pixel-exact canvas, so keep the TTF rasterizer
+    -- on that same 1x grid instead of inheriting the window DPI on mobile.
+    local ok, obj = pcall(love.graphics.newFont, file, size, "mono", 1)
     if ok and obj then
       -- nearest keeps the pixel font crisp under the integer UI scale
       if obj.setFilter then pcall(obj.setFilter, obj, "nearest", "nearest") end

tests/engine/ttf_font_mode.lua

@@ -40,6 +40,27 @@ T.eq(Font.advanceOf(0x80), 8, "and the pen stays 8px monospace")
 
 -- ------------------------------------------------- the ttf takes over
 
+-- Font rasterizers must use the same 1x pixel grid as PixelCanvas, rather
+-- than inheriting Android's window density.  Keep this local fake so the
+-- contract is testable without requiring a real LÖVE window.
+do
+  local g, oldNewFont = love.graphics, love.graphics.newFont
+  local args
+  g.newFont = function(...)
+    args = { ... }
+    return oldNewFont(Font.PLAINPIXEL, Font.PLAINPIXEL_SIZE)
+  end
+  local loaded, err = pcall(Font.load, {
+    font = { charmap = CHARMAP, ttf = { file = "custom.ttf", size = 13 } },
+  })
+  g.newFont = oldNewFont
+  if not loaded then error(err, 0) end
+  T.eq(args[1], "custom.ttf", "rasterizer uses the configured file")
+  T.eq(args[2], 13, "rasterizer uses the configured size")
+  T.eq(args[3], "mono", "rasterizer keeps the pixel hinting mode")
+  T.eq(args[4], 1, "rasterizer stays on the pixel canvas scale")
+end
+
 Font.load({ font = { charmap = CHARMAP, ttf = {} } })
 T.check(Font.ttfActive(), "an empty ttf table loads the bundled font")