Bug 47292

Summary: [chromium] Thumbnail generation asserts on zero alpha values.
Product: WebKit Reporter: Vincent Scheib <scheib>
Component: New BugsAssignee: Nobody <webkit-unassigned>
Status: RESOLVED FIXED    
Severity: Normal CC: commit-queue, kbr, nduca, scheib, vangelis
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Other   
OS: OS X 10.5   
Attachments:
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Description Vincent Scheib 2010-10-06 12:15:32 PDT 
[chromium] Thumbnail generation asserts on zero alpha values.
Comment 1 Vincent Scheib 2010-10-06 13:09:51 PDT 
Created attachment 69982 [details]
Patch
Comment 2 Vangelis Kokkevis 2010-10-06 13:26:21 PDT 
Comment on attachment 69982 [details]
Patch

View in context: https://bugs.webkit.org/attachment.cgi?id=69982&action=review

Otherwise, I agree with the proposed fix.

> WebCore/platform/graphics/chromium/LayerRendererChromium.cpp:288
> +    // Alpha channel on Windows is incorrect when Skia uses ClearType, don't write alpha:

I found the comment confusing.  Did you mean to punctuate differently?  How about:
Alpha channels on windows is incorrect when rendering text with ClearType.  Mask off alpha to maintain proper premultiplied color values in the backbuffer.

or something like that?
Comment 3 Kenneth Russell 2010-10-06 13:44:28 PDT 
Comment on attachment 69982 [details]
Patch

r- to address Vangelis's comments.
Comment 4 Vincent Scheib 2010-10-06 13:53:19 PDT 
Created attachment 69985 [details]
Patch
Comment 5 Kenneth Russell 2010-10-06 13:57:45 PDT 
Comment on attachment 69985 [details]
Patch

OK.
Comment 6 WebKit Commit Bot 2010-10-06 18:26:33 PDT 
Comment on attachment 69985 [details]
Patch

Clearing flags on attachment: 69985

Committed r69266: <http://trac.webkit.org/changeset/69266>
Comment 7 WebKit Commit Bot 2010-10-06 18:26:37 PDT 
All reviewed patches have been landed.  Closing bug.