Bug 243812

Summary: Handle transform changes causing overflow updates
Product: WebKit Reporter: Tim Nguyen (:ntim) <ntim>
Component: Layout and RenderingAssignee: zalan <zalan>
Status: REOPENED ---    
Severity: Normal CC: bfulgham, changseok, commit-queue, esprehn+autocc, ews-watchlist, glenn, kondapallykalyan, pdr, simon.fraser, webkit-bug-importer, zalan
Priority: P2 Keywords: InRadar
Version: WebKit Nightly Build   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on: 248959    
Bug Blocks:    
Attachments:
Description Flags
Patch
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[fast-cq]Patch none

Description Tim Nguyen (:ntim) 2022-08-10 20:39:26 PDT
// FIXME: transform changes really need to trigger layout. See RenderElement::adjustStyleDifference().

css/css-transforms/change-scale-wide-range.html is one affected WPT.
Comment 1 Radar WebKit Bug Importer 2022-08-10 20:39:54 PDT
<rdar://problem/98486403>
Comment 2 Tim Nguyen (:ntim) 2022-08-11 14:20:01 PDT Comment hidden (obsolete)
Comment 3 zalan 2022-09-10 14:58:12 PDT
Created attachment 462258 [details]
Patch
Comment 4 Tim Nguyen (:ntim) 2022-09-10 20:21:17 PDT
Comment on attachment 462258 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=462258&action=review

> Source/WebCore/rendering/RenderElement.cpp:258
> +            diff = std::max(diff, StyleDifference::SimplifiedLayout);

I wonder if we can clean up code around this FIXME: https://searchfox.org/wubkat/rev/7111cbd9fd80f1b153ea0d0a1805420bae87211c/Source/WebCore/rendering/RenderLayerCompositor.cpp#1775
Comment 5 zalan 2022-09-11 09:31:28 PDT
fast/repaint/multiple-backgrounds-style-change.html
^^ background image repaint optimization fails. We should certainly be able to identify this no-repaint case when there's no change in overflow.
Comment 6 zalan 2022-10-07 19:55:55 PDT
Created attachment 462873 [details]
Patch
Comment 7 zalan 2022-10-07 22:00:54 PDT
Created attachment 462876 [details]
Patch
Comment 8 zalan 2022-10-10 17:06:01 PDT
Created attachment 462918 [details]
[fast-cq]Patch
Comment 9 EWS 2022-10-11 14:40:36 PDT
Committed 255406@main (fc014916474a): <https://commits.webkit.org/255406@main>

All reviewed patches have been landed. Closing bug and clearing flags on attachment 462918 [details].
Comment 10 WebKit Commit Bot 2022-12-08 10:32:36 PST
Re-opened since this is blocked by bug 248959
Comment 11 Radar WebKit Bug Importer 2022-12-08 17:47:27 PST
<rdar://problem/103160679>