Bug 34383 - Do color animations on premultiplied colors
Summary: Do color animations on premultiplied colors
Alias: None
Product: WebKit
Classification: Unclassified
Component: CSS (show other bugs)
Version: 528+ (Nightly build)
Hardware: All OS X 10.5
: P2 Normal
Assignee: Simon Fraser (smfr)
: 34334 (view as bug list)
Depends on:
Reported: 2010-01-30 18:37 PST by Simon Fraser (smfr)
Modified: 2010-03-24 00:00 PDT (History)
2 users (show)

See Also:

Patch (5.05 KB, patch)
2010-01-30 18:39 PST, Simon Fraser (smfr)
adele: review+
Details | Formatted Diff | Diff

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Description Simon Fraser (smfr) 2010-01-30 18:37:39 PST
Per <http://lists.w3.org/Archives/Public/www-style/2009Jul/0048.html>, we should interpolate colors by first converting them to premultiplied alpha. This avoids the 'fade through gray' when animating from 'transparent' to an opaque color.
Comment 1 Simon Fraser (smfr) 2010-01-30 18:39:32 PST
Created attachment 47779 [details]
Comment 2 mitz 2010-01-30 18:45:41 PST
Comment on attachment 47779 [details]

It’s scary that Color can be either premultiplied or non-premultiplied.
Comment 3 Simon Fraser (smfr) 2010-01-30 19:22:05 PST
Comment 4 Simon Fraser (smfr) 2010-03-23 17:09:20 PDT
*** Bug 34334 has been marked as a duplicate of this bug. ***
Comment 5 Dirk Schulze 2010-03-23 23:58:30 PDT
Why not fixing premultipliedARGBFromColor directly? It affects other parts (mainly Cairo for what it was introduced) too.
Comment 6 Dirk Schulze 2010-03-24 00:00:29 PDT
premultipliedARGBFromColor is related to bug 30333