Bug 51397

Summary: CSS transparency rendering issue (opacity/rgba). Caused when animating <img>'s under element with transparency.
Product: WebKit Reporter: Luis Merino <mail>
Component: CSSAssignee: Nobody <webkit-unassigned>
Status: RESOLVED INVALID    
Severity: Normal CC: simon.fraser
Priority: P2    
Version: 528+ (Nightly build)   
Hardware: Mac (Intel)   
OS: OS X 10.6   
Attachments:
Description Flags
"Before"/"After" states of the issue. none

Luis Merino
Reported 2010-12-21 07:18:34 PST
Created attachment 77111 [details] "Before"/"After" states of the issue. CSS transparency rendering issue (opacity/rgba). Caused when animating <img>'s under element with transparency. It isn't possible for me at the moment to post a link or a resource for testing this, I'll do whenever possible, but I can provide my best demonstration: <div style="background:rgba(0,0,0.75)">Some text</div> // this is positioned absolute or fixed, doesn't matter. just on top of the images. <ul> // the stack is animated with JS, to create a slideshow effect, by modifying margin-left value, left/right transitions... <li><img src="..." alt="..." /></li> <li><img src="..." alt="..." /></li> </ul> I've attached a couple of screenshots. Notice how the visible part of the images under the <div> with the opacity value gets "cropped" instead of refreshed. This is corrected if any text is selected, or any other focus occurs inside "window", hence, it refreshes the rendering.
Attachments
"Before"/"After" states of the issue. (479.12 KB, image/jpeg)
2010-12-21 07:18 PST, Luis Merino 		no flags
Details
View All Add attachment proposed patch, testcase, etc.
Simon Fraser (smfr)
Comment 1 2010-12-21 12:33:33 PST
A testcase will be essential to tracking this down.
Simon Fraser (smfr)
Comment 2 2011-02-24 22:03:11 PST
Still need a testcase.
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