gaaclarke 576cdb40ff
[impeller] fixes diagonal antialiased lines (#166298)
fixes https://github.com/flutter/flutter/issues/166276

This fixes antialiased diagonal lines being a different width by doing
all prefiltered math in unrotated space, then applying a rotation to the
line. This avoids the oddity in the gpu gems 2 math.

## after photo

![IMG_7582](https://github.com/user-attachments/assets/26158d23-5416-420f-b092-18cbe00c7d57)

## without antialias

![IMG_7581](https://github.com/user-attachments/assets/fb913e56-15b1-46b4-af34-e4c7235eb21f)

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we expect every widget to implement].
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- [x] I listed at least one issue that this PR fixes in the description
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- [x] I updated/added relevant documentation (doc comments with `///`).
- [x] I added new tests to check the change I am making, or this PR is
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Fixes] where supported.
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2025-04-01 00:39:19 +00:00
..

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