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