Bug 61174 - REGRESSION (r81992): Element position doesn't update sometimes when style.left/top and style.webkitTransform set
Summary: REGRESSION (r81992): Element position doesn't update sometimes when style.lef...
Status: NEW
Alias: None
Product: WebKit
Classification: Unclassified
Component: Layout and Rendering (show other bugs)
Version: 528+ (Nightly build)
Hardware: Unspecified Unspecified
: P1 Normal
Assignee: Nobody
URL:
Keywords: Regression
Depends on:
Blocks:
 
Reported: 2011-05-20 01:32 PDT by James Robinson
Modified: 2011-05-20 10:16 PDT (History)
3 users (show)

See Also:

Attachments
test case (892 bytes, text/html)
2011-05-20 01:34 PDT, James Robinson 		no flags Details
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Description James Robinson 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.
Comment 1 James Robinson 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.
Comment 2 mitz 2011-05-20 08:54:06 PDT 
Is this the same as bug 60689?
Comment 3 Simon Fraser (smfr) 2011-05-20 10:16:52 PDT 
Looks like it.