linebender / linebender/vello

vello_hybrid: Incorrect early on on `!self.paint_visible`

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bug C-gpu
Dominant language
Rust
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Forks
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Avg merge
2d 13h
Merged PRs (30d)
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Description

In Vello Hybrid, in Scene::set_paint, it checks to see if the paint has an alpha of 0.0 and sets paint_visible to false.

Then, in Scene::fill_path and Scene::stroke_path, it has an early out based on that.

This is incorrect though as it depends on the blend mode.

If you have a blend mode that is COPY (or other things), then the operation should still happen.

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Research direction

Start by reading Scene::set_paint, Scene::fill_path, and Scene::stroke_path to trace how paint visibility and blend modes interact. Check the early-out behavior for transparent paint with COPY and other blend modes, then add or update coverage so operations that must still apply are not skipped.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
computer-graphics
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
45/100

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