GNOME Bugzilla – Bug 699370
Slow brush redraw bug w/ possible fix patch
Last modified: 2013-05-10 20:19:30 UTC
Created attachment 242985 [details] [review] The one-line patch that solved the issue for me uname -a Linux joshua-desktop 3.2.0-4-686-pae #1 SMP Debian 3.2.39-2 i686 GNU/Linux Brush drawing on the canvas was noticeably slow, constantly lagging behind the mouse cursor, making it very unclear where changes would be made on the image. In searching, I found bug #663582, in which Michael Natterer introduces a patch (https://bugzilla.gnome.org/review?bug=663582&attachment=225802) which involves delaying the brush draw by a timeout. I checked the source for 2.8.4 and checked the files gimpdrawtool.c. It looks like the patch is still there (though the line numbers don't match with the patch since the file has been since modified for other reasons). I commented out the "#define USE_TIMEOUT 0" line and recompiled. After doing this, the brush redraw is MUCH faster, resulting in a very perceptible increase in responsiveness to mouse movements. I haven't done extensive testing to make sure the change doesn't cause problems in other areas of the interface, but I believe this would be worth looking into for future versions.
Further information: Using NVIDIA Corporation GF108 [GeForce GT 430] (rev a1) GPU, with proprietary nvidia drivers, and xfce 4.8.
Confirming the improvement (Linux - git/gimp-2-8) This really improve the painting experience with a mouse and small brushes. But that timeout was originaly there for tablets... Thanks!
Well, with larges brushes and images, the change make things slower. It's still smoother though, the outline doesn't "jump".
Whatever is better, the discussion belongs into the original bug. *** This bug has been marked as a duplicate of bug 663582 ***