#2509 - Consult cmap format 14 (UVS) in shaping and subsetting - #2510
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swmal wants to merge 1 commit into
Open
#2509 - Consult cmap format 14 (UVS) in shaping and subsetting#2510swmal wants to merge 1 commit into
swmal wants to merge 1 commit into
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Summary
cmap format 14 (Unicode Variation Sequences) was parsed into
CmapSubtable14but never consulted during shaping, so a base character followed by a variation selector always rendered the default glyph instead of the registered variant (common in CJK).Changes
CmapTable: newTryGetGlyphId(base, selector)lookup against format 14.TextShaper.MapToGlyphs: lookahead that consumes a registered pair into one glyph.CmapSubsetProcessor: preserves variation-sequence data used by subsetted text, so the embedded PDF font matches the full font.CmapTableserialization: stopped dropping format 14 subtables; fixed a subtable-dedup bug this uncovered.CmapTableLoader/CmapSubtable14Deserializer: wired in and fixed existing-but-unused format 14 parsing (position wasn't restored between selector records).Testing
Unit tests for the lookup, shaping lookahead (BMP and surrogate-pair selectors), and a subsetting round-trip parity test. Full
EPPlus.Fonts.OpenTypesuite (410 tests) green. Manually verified via PDF export (BIZ UDGothic, U+585A + VS01) - distinct glyph IDs, confirmed visually.