[Transforms] Modifying transform values on relatively positioned elements fails to redraw

• Component: CSS
• Status: RESOLVED FIXED

[David Beck]

When changing the the value of a transform, such as rotate, on an element that has been positioned relatively, the areas outside where the element would be if it was not positioned at all, witll not change from the previous value.

I encountered this using the nightly build from 3-13-08 on Mac OS X 10.5.2

[David Beck]

Created attachment 19755 [details]
Example page

Example of when the failure occurs

[Simon Fraser (smfr)]

Created attachment 25084 [details]
Simpler testcase

[Simon Fraser (smfr)]

Created attachment 25088 [details]
Testcase to exercise the offsetForPositionedInContainer() code path

[Simon Fraser (smfr)]

Created attachment 25089 [details]
Patch

In RenderBox::computeAbsoluteRepaintRect(), the transform block clobbered topLeft after it had been adjusted for relative positioning, and for the offsetForPositionedInContainer().

The patch moves the topLeft adjustments until after the transform has been applied.

[Simon Fraser (smfr)]

Created attachment 25090 [details]
Followup patch to tidy up RenderBox::computeAbsoluteRepaintRect()

This is a follow-up patch that clean up RenderBox::computeAbsoluteRepaintRect():
* Do early return of container() is null
* if/else on style()->position()
* Make use of layer()->scrolledContentOffset()

[Dave Hyatt]

Comment on attachment 25089 [details]
Patch

r=me

[Dave Hyatt]

Comment on attachment 25090 [details]
Followup patch to tidy up RenderBox::computeAbsoluteRepaintRect()

r=me

[Simon Fraser (smfr)]

First patch: 

Committed r38338
	M	WebCore/rendering/RenderBox.cpp
	M	WebCore/ChangeLog
	A	LayoutTests/platform/mac/fast/repaint/transform-relative-position-expected.txt
	A	LayoutTests/platform/mac/fast/repaint/transform-absolute-in-positioned-container-expected.checksum
	A	LayoutTests/platform/mac/fast/repaint/transform-relative-position-expected.checksum
	A	LayoutTests/platform/mac/fast/repaint/transform-absolute-in-positioned-container-expected.png
	A	LayoutTests/platform/mac/fast/repaint/transform-absolute-in-positioned-container-expected.txt
	A	LayoutTests/platform/mac/fast/repaint/transform-relative-position-expected.png
	M	LayoutTests/ChangeLog
	A	LayoutTests/fast/repaint/transform-relative-position.html
	A	LayoutTests/fast/repaint/transform-absolute-in-positioned-container.html
r38338 = 71b2cc0a2f9a6d581a875f1c054e89e4e66a1d8c (trunk)

I fixed the tests to be real repaint tests.

[Simon Fraser (smfr)]

Second patch:
Committed r38339
	M	WebCore/rendering/RenderBox.cpp
	M	WebCore/ChangeLog
r38339 = a9261be41e86e2e97995671feb4eef8b3eaa2e45 (trunk)