[Webkit-unassigned] [Bug 82412] compositing/webgl/webgl-nonpremultiplied-blend.html is flaky on Lion

Wed Jul 4 13:49:44 PDT 2012

https://bugs.webkit.org/show_bug.cgi?id=82412

Kenneth Russell <kbr at google.com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|NEW                         |ASSIGNED
         AssignedTo|webkit-unassigned at lists.web |kbr at google.com
                   |kit.org                     |

--- Comment #5 from Kenneth Russell <kbr at google.com>  2012-07-04 13:49:44 PST ---
I think I see the problem. Because of how the premultiplied blend function of (ONE, ONE_MINUS_SRC_ALPHA) works, the premultipliedAlpha=false case for compositing of WebGL canvases is generally the first time the compositor will output anything except 1.0 for the alpha channel -- even when WebGL content is rendered with an alpha channel less than 1.0! A solution to this problem which seems correct to me is to disable writes to the alpha channel when drawing these canvases' output. This should cause the layout test results to be completely opaque on all platforms and fix any problems with weird content showing up blended behind them.

-- 
Configure bugmail: https://bugs.webkit.org/userprefs.cgi?tab=email
------- You are receiving this mail because: -------
You are the assignee for the bug.