Bug 66618

Summary: Reduce the amount of RenderLayer rectangle updating when scrolling
Product: WebKit Reporter: Julien Chaffraix <jchaffraix>
Component: Layout and RenderingAssignee: Julien Chaffraix <jchaffraix>
Status: RESOLVED FIXED    
Severity: Normal CC: hyatt, jamesr, simon.fraser, webkit.review.bot
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
Proposed optimization: Changed updateLayerPositions inside scrollTo for a beefed version of updateRepaintRectsAfterScroll. none

Julien Chaffraix
Reported 2011-08-19 18:49:11 PDT
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.
Attachments
Proposed optimization: Changed updateLayerPositions inside scrollTo for a beefed version of updateRepaintRectsAfterScroll. (74.20 KB, patch)
2011-08-19 19:05 PDT, Julien Chaffraix 		no flags
DetailsFormatted DiffDiff
View All Add attachment proposed patch, testcase, etc.
Julien Chaffraix
Comment 1 2011-08-19 19:05:24 PDT
Created attachment 104609 [details] Proposed optimization: Changed updateLayerPositions inside scrollTo for a beefed version of updateRepaintRectsAfterScroll.
Dave Hyatt
Comment 2 2011-08-23 10:31:36 PDT
Comment on attachment 104609 [details] Proposed optimization: Changed updateLayerPositions inside scrollTo for a beefed version of updateRepaintRectsAfterScroll. r=me
WebKit Review Bot
Comment 3 2011-08-23 11:02:59 PDT
Comment on attachment 104609 [details] Proposed optimization: Changed updateLayerPositions inside scrollTo for a beefed version of updateRepaintRectsAfterScroll. Clearing flags on attachment: 104609 Committed r93614: <http://trac.webkit.org/changeset/93614>
WebKit Review Bot
Comment 4 2011-08-23 11:03:04 PDT
All reviewed patches have been landed. Closing bug.
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