Version: unspecified (using Devel) OS: Linux After upgrading to 4.8 beta (currently using RC1) window decoration started being drawn quite slowly (about 1 second). I don't use desktop effects, because I have rather old graphics card: NVidia 7300. Reproducible: Always Steps to Reproduce: Open 2 windows and switch between them Actual Results: Window decorations (read: title bar) are drawn (read: color being changed) very slow. Expected Results: Change should be very quick. I tried it also under a new user and the switch was quick with desktop effects enabled, but in that case the title bars were somewhat broken - shifted to right a bit (so much that I couldn't see any buttons in the right corner).
Created attachment 67125 [details] Screencast This is how switching windows looks like
which Qt graphicssystem are you using?
What do you mean? Currently I have Qt 4.8.0 installed.
> What do you mean? Currently I have Qt 4.8.0 installed. so most likely you use graphicssystem raster. Try with native: kwin --replace --graphicssystem=native &
Ah, I see. Any way to disable raster graphicssystem without scripting? *** This bug has been marked as a duplicate of bug 284291 ***
https://git.reviewboard.kde.org/r/103430/ https://git.reviewboard.kde.org/r/103431/ I doubt the GUI part will make it for 4.8 (?!) but maybe we can still add the cofig item before 4.9 - no idea @Me alter the patch to preselect native w/o compositing enabled at startup
Actually, when I had desktop effects enabled, title bar was broken, but when I replaced kwin with native, title bars were OK. Does it make sense?
yes, known issue - your GPU presumingly doesn't support NPOT?! (do "glxinfo | grep GL_ARB_texture_non_power_of_two" - there's probably no output)
I have now upgraded to 4.10 RC3 and window decorations are drawn slowly again. It happens with desktop effects enabled and without, and also with "graphicssystem=native". Actually I do get an output for that: $ glxinfo | grep GL_ARB_texture_non_power_of_two GL_ARB_texture_mirrored_repeat, GL_ARB_texture_non_power_of_two,
[ ] You were using Plastik? [ ] You are now using QML based Plastik? [ ] The "Laptop" deco is still fast? -> QML hates the native graphicssystem, bug #313016 Please re-close this and hook there, but it's basically a won't fix (on the technical layer, qml likely won't ever be fast on the native system)
It was all Plastik indeed - if I set decorations to Oxygen it's OK. *** This bug has been marked as a duplicate of bug 284291 ***