[OpenJDK 2D-Dev] Reporitory, Accalerating blits with EA

Clemens Eisserer linuxhippy at gmail.com
Tue Jul 22 10:03:06 UTC 2008

> One thing that might explain the difference is whether or not the opaque
> destinations are considered premultiplied or not.  I believe that we
> consider them non-premultiplied in which case the extraalpha is multiplied
> in, the result is stored to the destination, which involves dividing the
> alpha back out == no change.  If the system treats the destinations as
> premultiplied then it multiplies the alpha into the color, then stores the
> multiplied (which looks faded) result into the destination...

Yes, I guess XRender treats the destination as premultiplied - at
least I guess it does not divide out the alpha at all.
Thanks a lot for the explanation :)

Thanks, Clemens

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