Fix pixel-grid misalignment caused by shared vertex insetting#5
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Aerhhh wants to merge 1 commit intominecraft-library:masterfrom
Open
Fix pixel-grid misalignment caused by shared vertex insetting#5Aerhhh wants to merge 1 commit intominecraft-library:masterfrom
Aerhhh wants to merge 1 commit intominecraft-library:masterfrom
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_inset_shared_vertices nudged shared contour vertices by 1 font unit along the bisector of adjacent edges to suppress a FontForge wrong-direction false positive. This moved outline coordinates off the pixel grid (e.g. (127, 769) instead of (128, 768)), causing font rasterizers (FreeType, Java2D) to produce platform-dependent rendering artifacts on characters with multiple contours (A, M, H, S, K, etc.). Removing the function restores all glyph coordinates to exact multiples of 128 font units (1 Minecraft pixel at UPM 1024 / 8ppem), producing clean pixel-perfect rendering at all integer multiples of the native design size.
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Summary
_inset_shared_verticeswhich nudged shared contour vertices by 1 font unit off the pixel gridProblem
_inset_shared_verticeswas introduced to suppress a FontForge wrong-direction false positive on glyphs where outer and hole contours share a vertex. It shifts those vertices by 1 font unit along the bisector of adjacent edges.This moves outline coordinates off the pixel grid - for example
(127, 769)instead of(128, 768). When font rasterizers (FreeType on Linux, Java2D, etc.) encounter these off-grid coordinates, they make different rounding decisions depending on the platform, producing inconsistent rendering artifacts on characters with multiple contours (A, M, H, S, K, and many others).Before (off-grid coordinates for 'A'):
After (grid-aligned):
Rendering comparison (Python/Pillow at 16px)
Before - 'A' has asymmetric strokes:
After - clean 2x pixel grid: