)]}'
{
  "commit": "289f4919b58e349ccbca39fe23e8cd3d0acadc86",
  "tree": "39ba87cb611341e60c2a03b9bfb3fad46f03753a",
  "parents": [
    "537f7d1da25815e73fba2cdeaf4073eb2c8c04b8"
  ],
  "author": {
    "name": "Taj Pereira",
    "email": "taj@canva.com",
    "time": "Wed Sep 17 09:50:20 2025 +1000"
  },
  "committer": {
    "name": "GitHub",
    "email": "noreply@github.com",
    "time": "Tue Sep 16 23:50:20 2025 +0000"
  },
  "message": "Glyph Caches: Hinting Instances + Outline Paths (#1215)\n\nWe found that ~80% of the time in preparing a glyph to render is in\nbuilding hinting instances and extracting glyph outlines as shown by the\nbelow profile.\n\n\u003cimg width\u003d\"1751\" height\u003d\"608\" alt\u003d\"image\"\nsrc\u003d\"https://github.com/user-attachments/assets/6b862072-15b8-4ffc-b6e0-069ee38e4a9b\"\n/\u003e\n\n\nThis PR adds LRU caches for hinting instances and getting outlines. The\nstrategy mimics the one used by [Vello\nClassic](https://github.com/linebender/vello/blob/main/vello_encoding/src/glyph_cache.rs)\nfor simplicity.\n\nThe outline cache grows to accommodate all the glyphs that can be\nrendered in a given frame and runs its eviction process within the\nrenderer\u0027s `flush` function. Since outlines are relatively cheap on\nmemory, I think that this approach is better than checking cache bounds\non each access.\n\nNote: This implies that `flush` must always be called once per frame for\nhybrid like vello cpu. But, I think this is fine. It\u0027s likely we\u0027ll want\nto run some things in a multi threaded environment in hybrid at some\npoint.\n\nDepending on the text being rendered, we\u0027ve observed significant boosts\nto performance using this PR. In Vello Hybrid testing, for a super\nsimple text field, we\u0027ve observed 100+ FPS boost. It\u0027s hard to tell at\nthis stage what real world performance will be seen.\n\n## Future Work\n\n- Only pay for `font_ref.outline_glyphs()` when we actually need it or\nuse an acceleration data structure to generate it.\n- Instead of storing outline paths in the outline cache, store\ntranslatable strips (to totally bypass strip rendering).",
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