1458798 - Clear mPreviousTimeStamp when we skip calling SampleAnimations in CompositeToTarget()

Status: RESOLVED FIXED

(Core :: Graphics: WebRender, enhancement, P1)

Description

[Hiroyuki Ikezoe (:hiro)]

When we skip calling SampleAnimations() we should clear mPreviousTimeStamp, otherwise we will use the timestamp that is far behind from the timestamp on the main-thread, that leads visual gaps for animations.

This change should fix failures that happened when the patches for bug 1456679 landed.

A try with patches for bug 1456679 and bug 1458457.
https://treeherder.mozilla.org/#/jobs?repo=try&revision=6868cfe1c27e577106084fbb6b5ec10483a98a77

And here is a try only with the patch for this bug.
https://treeherder.mozilla.org/#/jobs?repo=try&revision=444751fca3735a0098a2a4fbf3fe46f6f4fefa54

Comment 1

[Hiroyuki Ikezoe (:hiro)]

Attachment: Bug 1458798 - Clear the previous timestamp when we skip calling SampleAnimations in CompositeToTarget().

The purpose of the previous timestamp is to reduce the time difference between
the timestamps on the main-thread and the compositor.  Once we skipped a frame
to compose animations on the compositor, the timestamp is far behind from the
timestamp on the main-thread, so we should clear it.

Review commit: https://reviewboard.mozilla.org/r/241346/diff/#index_header
See other reviews: https://reviewboard.mozilla.org/r/241346/

Comment 2

[Kartikaya Gupta (email:[e-mail])]

Comment on attachment 8972782 [details]
Bug 1458798 - Clear the previous timestamp when we skip calling SampleAnimations in CompositeToTarget().

https://reviewboard.mozilla.org/r/241346/#review247210

I don't really like that this is duplicated and separated from the rest of the code in AdvanceAnimations(), but I can't think of a better way to structure it to, so r+. We can always change it later if we find a better way to do this.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/da163bfbc6c8
Clear the previous timestamp when we skip calling SampleAnimations in CompositeToTarget(). r=kats

Comment 4

[Andrei Ciure[:aciure]]

https://hg.mozilla.org/mozilla-central/rev/da163bfbc6c8