1860310 - CSS gradients not anti-aliased

Status: UNCONFIRMED

(Core :: Graphics: WebRender, defect)

Description

[R. N. West [:rnwst]]

Attachment: gradients.html

CSS gradients are not anti-aliased. See the attached test case. The test case only includes a radial and a conic gradient, but the issue occurs with linear gradients as well. I can submit a separate test case for that if desired.

FF versions:

• 120.0a1 (2023-10-17) (64-bit)
• 118.0.2 (64-bit)

Comment 1

[R. N. West [:rnwst]]

Attachment: gradients.png

This image is a screenshot of the test case, which was up-scaled without interpolation, to make the effect more easily visible.

Comment 2

[Mayank Bansal]

I get similar rendering in Chrome too.

Comment 3

[Alice0775 White]

I can also reproduce this on Windows10.

Regression window on Windows10:
https://hg.mozilla.org/integration/autoland/pushloghtml?fromchange=3c36156a38e3738afe6488ea8cfce7cbbc7e0c6b&tochange=6567bdeb3c1e97a75f12fd72d92a6fb4a2cfcc91

Comment 4

[R. N. West [:rnwst]]

FWIW, this is also an issue on Chromium, as mentioned above. The corresponding report was filed over 9 years ago, and there is still no fix:
https://bugs.chromium.org/p/chromium/issues/detail?id=408528

Comment 5

[Alice0775 White]

Attachment: screenshot on Windows10

On Windows10 WebRender(HW and SW), pixel jaggedness is unusually large in places.

Comment 6

[Sotaro Ikeda [:sotaro]]

:gw, can you comment to the bug?