At display scaling other than 100% (DPR ≠ 1), the OpenGL canvas renders text with visibly uneven stroke widths because glyph positions snap to CSS pixel boundaries rather than physical pixel boundaries, and pixel-grid alignment is disabled entirely for all non-1× DPR values.

Root causes

• AlignToPixelGrid snapped to CSS pixel grid, not physical pixel grid. floor(v.x) + 0.5 centers on integer CSS pixels. At DPR=1.5, those land at 0.0, 1.5, 3.0… physical pixels — every other position off-center, producing alternating 1- and 2-pixel-wide strokes.

• gridFit unconditionally disabled for DPR ≠ 1, so no pixel alignment was applied at any scaled DPI. The guard existed because the old snap formula was wrong for non-1× DPR.

• (Web only) Canvas CSS display size not explicitly set after emscripten_set_canvas_element_size. The width: 100% rule could resolve to a fractional CSS size that doesn't divide evenly by DPR, causing the browser to apply bilinear interpolation over the bitmap.

Changes

• src/render/render.cpp — Fix AlignToPixelGrid to snap to physical pixel centers for any DPR:

  // Before: snaps to CSS pixel centers only (correct at DPR=1, wrong otherwise)
  v.x = floor(v.x) + 0.5;
  
  // After: snaps to physical pixel centers at any DPR
  v.x = (floor(v.x * pixelRatio) + 0.5) / pixelRatio;

• src/draw.cpp, src/textwin.cpp — Set gridFit = true unconditionally (was GetDevicePixelRatio() == 1). The fixed snap formula handles all DPR values correctly.

• src/platform/guihtml.cpp — After resizing the canvas bitmap, override the inline CSS size to pixelWidth / DPR × pixelHeight / DPR px, ensuring the browser maps the bitmap 1:1 to physical pixels without any interpolation pass.