[PD] GEM pix cropping with a polygon

[rainer _]

hi,
i'm just wondering if there's a way to do pix cropping with a polygon in GEM 
? just similar to the pix_crop object but with a polygon.
also the pix_data object seems to be somehow faulty in GEM 0.90 (compiled 3. 
Aug. 04). everything becomes very slow if i bang it with a fast metro in 
single buffered mode. Same constellation works great with GEM 0.87+CVS 
(compiled 9. Aug. 03) + winXP.....

thanks,
rainer