Hi Sven - Code snippet: (while (< y height) (gimp-rect-select inImage 0 0 width y REPLACE FALSE 0) ; select some pixels (gimp-edit-copy maskchannel) ; copy the selection (gimp-selection-translate inImage 0 y) ; shift down (gimp-floating-sel-anchor (car (gimp-edit-paste maskchannel FALSE))) ; and paste back (set! y (+ y y)) ; move down by as much as we did ) The snippet above no longer has the anomaly at y = 256; instead it's around y = 150. The snippet below has the anomaly at y = 2 ^ n: (while (< y height) (gimp-rect-select inImage 0 0 width y REPLACE FALSE 0) ; select some pixels (gimp-edit-copy maskchannel) ; copy the selection (gimp-selection-translate inImage 0 y) ; shift down (gimp-floating-sel-anchor (car (gimp-edit-paste maskchannel TRUE))) ; and paste back (set! y (+ y y)) ; move down by as much as we did ) The location of the anomaly depends on the second argument to gimp-edit-paste, which I don't really understand anyway. The problem does not arise when the image's y dimension is a power of 2. (Or maybe it's some multiple of the step size: the initial step I've been using has been 4). To make life more interesting, I can't find it when the initial step size is 5. I'll continue to research this and file a bug report when I can figure out what's really going on. -- --Jeff Jeff Trefftzs <trefftzs@xxxxxxxx> http://www.tcsn.net/trefftzs Home Page http://gug.sunsite.dk/gallery.php?artist=68 Gimp Gallery http://trefftzs.topcities.com/home.html Photo galleries
