[cairo] Road to 1.10

Kristian Høgsberg krh at bitplanet.net
Mon Feb 16 07:27:48 PST 2009

On Mon, Feb 16, 2009 at 6:30 AM, Emmanuele Bassi <ebassi at linux.intel.com> wrote:
> On Mon, 2009-02-16 at 10:06 +0000, Chris Wilson wrote:
>> On a more wider topic, having played with wayland and creating a
>> cairo-based compositor, we sorely lack the ability to use a
>> non-premultiplied source (such as an OpenGL window, or SDL surface as
>> fairly trivial to handle in a shader. (Slightly more work to add the
>> extra code paths to pixman though!)
> one of the hits we get when using Cairo in Clutter comes from the
> unpremultiplication of the alpha channel when uploading an image surface
> into a GL texture. it's a one-off operation, but done for a lot of
> textures, and if the textures are changing their size (e.g. during an
> animation involving width/height properties) then it causes performance
> issues -- on top of the usual performance implications of using an image
> surface.

Is there a reason you can't just set


Or am I missing something?


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