Bug 55514

Summary: [chromium] invalidating a rotated border causes different pixels to be painted
Product: WebKit Reporter: Tony Chang <tony>
Component: WebCore Misc.Assignee: Nobody <webkit-unassigned>
Status: RESOLVED WONTFIX    
Severity: Normal CC: jamesr, schenney, senorblanco
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: PC   
OS: OS X 10.5   
Attachments:
Description Flags
test case
none
better test case
none
initial load
none
after invalidate none

Tony Chang
Reported 2011-03-01 15:01:27 PST
Repro steps: 1) Load the attached file in test_shell.exe. You should see a box rotated 20deg. 2) Drag the window off screen and back. 3) If you look carefully, you'll see that the edge is now a tiny bit different (a bit darker?). If you reload, the edges return to the lighter state. I suspect this is a problem in skia since I couldn't repro on mac. It's also hard to repro on Chromium because it saves a backing store of the image. It's the extra invalidate that causes the border to change.
Attachments
test case (255 bytes, text/html)
2011-03-01 15:01 PST, Tony Chang 		no flags
Details
better test case (342 bytes, text/html)
2011-03-01 15:54 PST, Tony Chang 		no flags
Details
initial load (22.04 KB, image/png)
2011-03-01 15:55 PST, Tony Chang 		no flags
Details
after invalidate (21.79 KB, image/png)
2011-03-01 15:56 PST, Tony Chang 		no flags
Details
Show Obsolete (1) View All Add attachment proposed patch, testcase, etc.
Tony Chang
Comment 1 2011-03-01 15:01:47 PST
Created attachment 84303 [details] test case
James Robinson
Comment 2 2011-03-01 15:15:24 PST
Can you post before/after screenshots of what you are seeing?
Tony Chang
Comment 3 2011-03-01 15:54:57 PST
Created attachment 84314 [details] better test case
Tony Chang
Comment 4 2011-03-01 15:55:31 PST
Created attachment 84315 [details] initial load
Tony Chang
Comment 5 2011-03-01 15:56:04 PST
Created attachment 84316 [details] after invalidate
Tony Chang
Comment 6 2011-03-01 15:56:42 PST
(In reply to comment #3) > Created an attachment (id=84314) [details] > better test case This shows a much more noticeable difference. The original test case only differed by a dozen pixels or so.
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