[Webkit-unassigned] [Bug 86429] New: RenderLayer::repaintRectIncludingDescendants shouldn't include repaint rects of composited descendants

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=86429

           Summary: RenderLayer::repaintRectIncludingDescendants shouldn't
                    include repaint rects of composited descendants
           Product: WebKit
           Version: 528+ (Nightly build)
          Platform: Unspecified
        OS/Version: Unspecified
            Status: NEW
          Keywords: InRadar
          Severity: Normal
          Priority: P2
         Component: Layout and Rendering
        AssignedTo: webkit-unassigned at lists.webkit.org
        ReportedBy: timothy_horton at apple.com
                CC: simon.fraser at apple.com


As it stands, we can end up unioning a rect with a page-relative origin and a rect with a 0,0 origin (the compositing layer), creating huge repaint rects with some content. Composited descendants don't need to be factored in here (the only use of repaintRectIncludingDescendants is in scrollContentsFathPath, and composited layers won't need to be invalidated manually there).

This is a significant scrolling performance win on some pages.

<rdar://problem/11445132>

-- 
Configure bugmail: https://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.