[Webkit-unassigned] [Bug 66618] New: Reduce the amount of RenderLayer rectangles' update when scrolling

[bugzilla-daemon at webkit.org]

https://bugs.webkit.org/show_bug.cgi?id=66618

           Summary: Reduce the amount of RenderLayer rectangles' update
                    when scrolling
           Product: WebKit
           Version: 528+ (Nightly build)
          Platform: Unspecified
        OS/Version: Unspecified
            Status: NEW
          Severity: Normal
          Priority: P2
         Component: Layout and Rendering
        AssignedTo: webkit-unassigned at lists.webkit.org
        ReportedBy: jchaffraix at webkit.org
                CC: hyatt at apple.com, simon.fraser at apple.com,
                    jamesr at chromium.org


Currently whenever scrollTo is called on a RenderLayer (programmatic or mouse scroll), we call updateLayerPositions(0) which automatically updates the repaint rectangles. However the call paths make sure that a layout is done prior to calling scrollTo. This means that updateLayerPositions() has already been called to make sure everything is up-to-date. Thus we are computing the layers (positions / repaint rects) twice for elements that would not move (basically anything not fixed).

Patch forthcoming to avoid this double calculation.

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