On Tue, 11 Mar 2003 09:46:49 +0000, "Adam D. Moss" <adam@xxxxxxxx> wrote: > [...] The idea > of rehash-on-dirty would be to catch identical tiles, even > accidentally-identical tiles (like great masses of transparent > tiles, presuming that you scrub the RGB data of a transparent > pixel; the row-hints stuff has been doing this and potentially > breaking the ill-advised anti-erase feature for 100 years now > and no-one has complained), that the normal COW routes miss. Hmmm... This is interesting. I didn't know that a side effect of the row-hints would be to discard the RGB data from fully transparent pixels. Of course, this makes sense and this is the right thing to do. But this also means that some plug-ins such as Noisify should definitely never use the invisible RGB data in any operation, because the results could be (very) different if some tiles are swapped out. See the discussion in: http://bugzilla.gnome.org/show_bug.cgi?id=72853 -Raphaël