On Thu, 18 Nov 2004 12:03:21 -0200, Joao S. O. Bueno Calligaris > Hi... > So, my point is that for getting the best possible performance a > "realtime preview" of any tool not able to do it's job in realtime > would have to be applyed after the crop and scale in this diagram - > and them, the Image Data would be changed in a background thread. > >snip< > > scale down. Thus, even letting most of the work to GEGL, a dual layer > tree - one for displaying, and one for the actual data, may still be > a good solution. For real time preview, there is only one tree, the tree for displaying, there is no need to calculate anything outside the view port,. nor to operate on a full size image. Even a brush stroke can be considered an Op in GEGL,. during interactive use that op would have properties that are the path, the brush used, the paint mode, and the color used. The path would be grown incrementally. For both approaches, a single compositing tree that is optimized according the the requested output size, and two separate pipelines the same amount of calculation of brush size etc needs to be done. The benefit of having a single unified tree is a cleaner design without having to keep track of two data models in the gimp at all times. /pippin -- Software patents hinder progress | http://swpat.ffii.org/ Web : http://pippin.gimp.org/