1801588 - [HWA] "copy" composite mode doesn't work anymore

Status: RESOLVED FIXED

(Core :: Graphics: Canvas2D, defect)

Description

[Kaiido]

Attachment: test-case.html

User Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:107.0) Gecko/20100101 Firefox/107.0

Steps to reproduce:

0. Ensure to have gfx.canvas.accelerated flag set on.
1. Draw some content over a Canvas2D context.
2. Set the context's globalCompositeOperation (gCO) mode to "copy".
3. Draw something new on the context.

Actual results:

The new content is drawn on top of the existing content as if the gCO was set to "source-over".

Expected results:

The new content should have replaced the existing content entirely, i.e only the last drawn content should be visible.

Note that drawImage() behaves even weirder where transparent pixels of the source image actually erase the content below. Sounds like there is an issue with the clipping region.

Comment 1

[Kaiido]

Attachment: Screenshot of the issue as seen in Nightly 109.0a1 on macOS Ventura 13.0.1

Comment 2

[Mayank Bansal]

Bug 1779681 - Mark WebGL framebuffer as initially valid in DrawTargetWebgl. r=aosmond,gfx-reviewers

mWebglValid gets initialized to false, but it will never get reset to true until the next
frame, causing us to render into Skia the first frame rather than accelerate. Therefor, we
should just initialize it to valid. Since it is cleared to zero initially, this is safe.

Differential Revision: https://phabricator.services.mozilla.com/D151896

2022-11-21T12:39:51.574000: DEBUG : Did not find a branch, checking all integration branches
2022-11-21T12:39:51.577000: INFO : The bisection is done.
2022-11-21T12:39:51.635000: INFO : Stopped

Comment 3

[BugBot [:suhaib / :marco/ :calixte]]

Set release status flags based on info from the regressing bug 1779681

Comment 4

[Lee Salzman [:lsalzman]]

Attachment: Bug 1801588 - Ensure region outside mask but inside clip is cleared for copy op. r?aosmond

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/26208f1c96fb
Ensure region outside mask but inside clip is cleared for copy op. r=aosmond

Comment 6

[Cristian Tuns]

https://hg.mozilla.org/mozilla-central/rev/26208f1c96fb