fix(text): render Devanagari and other complex scripts correctly#8895
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fix(text): render Devanagari and other complex scripts correctly#8895willeastcott wants to merge 1 commit into
willeastcott wants to merge 1 commit into
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getSymbols now keeps a base character together with its trailing combining marks, ZWJ/ZWNJ joiners and virama-joined consonants as a single grapheme cluster. This lets CanvasFont shape whole syllables via the browser's text shaper, instead of laying out each code point as a separate glyph. Fonts with per-code-point atlases (bitmap/MSDF) expand any missing cluster back to its code points, so they render as before. Fixes #4102 Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
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Fixes #4102.
string.getSymbolssplit Devanagari into one symbol per code point, so vowel signs (matras) detached from their consonant and conjuncts never formed — text rendered garbled and out of order as reported.getSymbolsnow forms proper grapheme clusters: a base character plus its trailing combining marks (\p{M}),ZWJ/ZWNJjoiners and virama-joined consonants. BecauseCanvasFontrasterizes each symbol with the browser's text shaper, whole syllables now shape into a single correctly-composed glyph (Devanagari, plus Arabic, Tamil, etc.).Bitmap/MSDF fonts have per-code-point atlases that don't contain a multi-code-point cluster, so
TextElementexpands any font-missing cluster back into its code points — they render exactly as before.Tested: added
getSymbolsunit tests for Devanagari vowel signs and conjuncts; existing emoji/flag/ZWJ cases are unchanged; verified end-to-end that a realCanvasFontatlas now contains correctly-shaped Hindi clusters.🤖 Generated with Claude Code