Bug 228120

Summary: Layer tree unfreezing and rendering update scheduling need to work together
Product: WebKit Reporter: Simon Fraser (smfr) <simon.fraser>
Component: Layout and RenderingAssignee: Nobody <webkit-unassigned>
Status: NEW ---    
Severity: Normal CC: bfulgham, sam, simon.fraser, webkit-bug-importer, zalan
Priority: P2 Keywords: InRadar
Version: Safari Technology Preview   
Hardware: Unspecified   
OS: Unspecified   
See Also: https://bugs.webkit.org/show_bug.cgi?id=228121

Description Simon Fraser (smfr) 2021-07-20 12:31:27 PDT
We currently rely on timers to trigger style updates/render tree updates, and this is necessary to trigger unfreezing the layer tree (via visually empty threshold). Ideally the style system would not have any of its own timers; it would just schedule rendering updates. However, TiledCoreAnimationDrawingArea::triggerRenderingUpdate() just bails if the layer tree is frozen.

We need to somehow harmonize layer tree freezing with rendering updates.
Comment 1 Simon Fraser (smfr) 2021-07-20 12:32:00 PDT
See rdar://75362363 and http://trac.webkit.org/changeset/272300/webkit
Comment 2 Sam Weinig 2021-07-21 16:57:12 PDT
(In reply to Simon Fraser (smfr) from comment #1)
> See rdar://75362363 and http://trac.webkit.org/changeset/272300/webkit

... and https://trac.webkit.org/changeset/280112/webkit
Comment 3 Radar WebKit Bug Importer 2021-07-27 12:32:20 PDT