1129245 - Wrong values for some 3d transforms with off main thread animation (OMTA) enabled

Status: RESOLVED FIXED

(Core :: CSS Parsing and Computation, defect)

Description

[Brian Birtles (:birtles, Feb 26~ parental leave)]

Attachment: Iframe document

In the upcoming test case, a 3d transform is transitioned on two different elements, then, after the transitions have finished, a 3d transform animation begins on one of them. When the transitions finish and the animation starts the elements seem to jump but only when OMTA is enabled.

The test case loads an iframe document. Loading the iframe document standalone does not exhibit the bug.

This could well be a dupe of something like bug 847287 but I'm filing it separate now until we know for sure.

Comment 1

[Brian Birtles (:birtles, Feb 26~ parental leave)]

Attachment: Test case

Comment 2

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

I thought we try not to OMTA 3D transforms.  Could be related to some of the overriding bugs that are also dependencies of bug 980770.

Comment 3

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

Does this still seem broken to you?  I don't think I see anything different between OMTA enabled and disabled.

If it does, could you describe the difference a bit better?

Comment 4

[Brian Birtles (:birtles, Feb 26~ parental leave)]

Yes, it's still broken. There's a sudden jump when the transitions finish and the animations start. I'll see if I can make a screencast.

Comment 5

[Brian Birtles (:birtles, Feb 26~ parental leave)]

Attachment: Screencast

Sorry about the video format, I just updated VLC media player and it now crashes whenever I try to convert to WebM.

Comment 6

[David Baron :dbaron: (⌚️UTC-4, no longer working on Mozilla)]

I still don't see this bug on Linux, with OMTA enabled, including in a nightly from January 6 and one from April 14.

Comment 7

[Brian Birtles (:birtles, Feb 26~ parental leave)]

(In reply to David Baron [:dbaron] ⏰UTC-7 from comment #6)
> I still don't see this bug on Linux, with OMTA enabled, including in a
> nightly from January 6 and one from April 14.

This is working for me now. I'm not sure which bug fixed it, however, or if its worth tracking down.