Bug 131889

Summary: Incomplete body painting when using blend modes
Product: WebKit Reporter: Simon Fraser (smfr) <simon.fraser>
Component: Layout and RenderingAssignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Normal CC: cabanier, commit-queue, esprehn+autocc, glenn, kondapallykalyan, krit, mihnea, rosca, simon.fraser, webkit-bug-importer
Priority: P2 Keywords: InRadar
Version: 528+ (Nightly build)   
Hardware: Unspecified   
OS: Unspecified   
Bug Depends on:    
Bug Blocks: 95614    
Attachments:
Description Flags
Testcase
none
simplified version
none
Patch none

Description Simon Fraser (smfr) 2014-04-19 10:57:41 PDT
Created attachment 229736 [details]
Testcase

Attached testcase (fix it to point to a local copy of ducky.png) shows a bug where the body background is only partially painted. It flashes horribly when hovering the boxes.
Comment 1 Simon Fraser (smfr) 2014-04-19 10:58:36 PDT
This is a blocker to Safari shipping blend modes.

<rdar://problem/16668770>
Comment 2 Rik Cabanier 2014-04-20 20:54:11 PDT
Created attachment 229781 [details]
simplified version

even simpler version. This has to be a recent break since basic content is now drawing incorrectly.
Comment 3 Rik Cabanier 2014-04-20 23:14:03 PDT
It looks like this was caused by https://bugs.webkit.org/show_bug.cgi?id=130892
Comment 4 Mihnea Ovidenie 2014-04-23 10:23:28 PDT
(In reply to comment #3)
> It looks like this was caused by https://bugs.webkit.org/show_bug.cgi?id=130892

Nope, it's https://bugs.webkit.org/show_bug.cgi?id=129154.
Comment 5 Ion Rosca 2014-04-24 02:24:47 PDT
I'm looking into it.
Comment 6 Ion Rosca 2014-04-24 23:16:44 PDT
Created attachment 230143 [details]
Patch
Comment 7 Ion Rosca 2014-04-24 23:25:35 PDT
The patch I attached avoids creating a transparency layer for the root renderer that has unisolated blending descendants. However, the issue with background being painted incompletely is not fixed for other reasons that trigger transparency layers on the document element: opacity, mask or mix-blend-mode. This issue is reported here: https://bugs.webkit.org/show_bug.cgi?id=75460.
Comment 8 WebKit Commit Bot 2014-04-25 01:04:57 PDT
Comment on attachment 230143 [details]
Patch

Clearing flags on attachment: 230143

Committed r167796: <http://trac.webkit.org/changeset/167796>
Comment 9 WebKit Commit Bot 2014-04-25 01:05:02 PDT
All reviewed patches have been landed.  Closing bug.