Bug 61174

Summary: REGRESSION (r81992): Element position doesn't update sometimes when style.left/top and style.webkitTransform set
Product: WebKit Reporter: James Robinson <jamesr>
Component: Layout and RenderingAssignee: Nobody <webkit-unassigned>
Status: NEW    
Severity: Normal CC: hyatt, mitz, simon.fraser
Priority: P1 Keywords: Regression
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Attachments:
Description Flags
test case none

James Robinson
Reported 2011-05-20 01:32:37 PDT
See testcase. The issue seems to be that if style.left is set to a new value and style.webkitTransform is set to the same value it previously had ("scale(1" in this case), its layout does not update. This caused some animation code we had to appear very jerky as sometimes the elements would stay stuck for many frames at a time.
Attachments
test case (892 bytes, text/html)
2011-05-20 01:34 PDT, James Robinson 		no flags
Details
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James Robinson
Comment 1 2011-05-20 01:34:29 PDT
Created attachment 94189 [details] test case In this test case, the top and bottom blocks always have the same specified style.left value. The top block has its webkitTransform set to a scale on each tick such that it receives the same scale() value for 4 frames in a row and a very slightly different value for 1 frame, repeating.
mitz
Comment 2 2011-05-20 08:54:06 PDT
Is this the same as bug 60689?
Simon Fraser (smfr)
Comment 3 2011-05-20 10:16:52 PDT
Looks like it.
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