On Wednesday 26 May 2010, Soeren Sandmann wrote: > > From: Siarhei Siamashka <siarhei.siamas...@nokia.com> > > OVER can't be reduced to SRC because the source image is not > > considered opaque when repeat is set to PIXMAN_REPEAT_NONE. > > An additional fast path table entry solves the problem. > > It solves the problem for r5g6b5 on NEON, but not in any other > cases. We have the same issue on every backend with every format > without alpha. Adding special cases for all of them would quickly get > unwieldy (and actually be impossible for the general implementation).
Yes, this "solution" indeed has a problem that only a certain small subset of operations is supported. That's not much different from the current pixman design using fast path functions, but just pushes its disadvantages to extreme :) On a positive side, not so many operations are actually showing up in real applications and this r5g6b5 OVER r5g6b5 is a rare one which is actually needed in practice. > Would it be possible instead to add a new flag "OPAQUE_SAMPLES" that > would be set whenever the image format is opaque, and then use it > along with SAMPLES_COVER_CLIP to add the OPAQUE flag before strength > reducing the operator? > > That would help all the backends, including the general one, and all > the opaque image formats. OK, I'll try to see what can be done. I'm a bit worried about the applications using pixman in such a way that the pixels outside of the source image are also fetched and whether this will be handled efficiently with the new flag. -- Best regards, Siarhei Siamashka _______________________________________________ Pixman mailing list Pixman@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/pixman