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
Created attachment 19755 [details] Example page Example of when the failure occurs
Created attachment 25084 [details] Simpler testcase
Created attachment 25088 [details] Testcase to exercise the offsetForPositionedInContainer() code path
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.
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()
Comment on attachment 25089 [details] Patch r=me
Comment on attachment 25090 [details] Followup patch to tidy up RenderBox::computeAbsoluteRepaintRect() r=me
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.
Second patch: Committed r38339 M WebCore/rendering/RenderBox.cpp M WebCore/ChangeLog r38339 = a9261be41e86e2e97995671feb4eef8b3eaa2e45 (trunk)