Version: 4.8.0 (using Devel) OS: Linux It is hard to explain bug in words so I made video. Look closely above pop-up menus. You will see little artifacts. After extensive testing I found out that "scale in" effect is causing this. Video: http://www.youtube.com/watch?v=YUBPBdccivU&context=C3fd8758ADOEgsToPDskLwQ33Zwt2veNXRSMRySxrg Reproducible: Always Steps to Reproduce: 1) Enable scale in effect. 2) Open some KDE (Qt) application. 3) Navigate through menus (file, edit, view etc) back and forth. Actual Results: Little artifacts appear above pop-up menus. Expected Results: No artifacts.
Looks like an issue with texture clamping on scaled textures. (That region is actually still part of the popup shadow and should match the area where the upper right corner touches the top center) a) this is on the OpenGL backend, correct? b) does it only happen with "kwin --replace --graphicssystem raster &" or "kwin --replace --graphicssystem native &" or with both? c) kwin or kwin_gles ? d) On what GPU and driver (attach a glxinfo dump or the output of kwin when started from konsole)
(In reply to comment #1) > Looks like an issue with texture clamping on scaled textures. > (That region is actually still part of the popup shadow and should match the > area where the upper right corner touches the top center) > > a) this is on the OpenGL backend, correct? yes > b) does it only happen with "kwin --replace --graphicssystem raster &" or "kwin > --replace --graphicssystem native &" or with both? with both > c) kwin or kwin_gles ? kwin > d) On what GPU and driver (attach a glxinfo dump or the output of kwin when > started from konsole) mobility radeon hd 2400 snele@KDevil:~$ OpenGL vendor string: X.Org OpenGL renderer string: Gallium 0.4 on AMD RV610 OpenGL version string: 2.1 Mesa 7.12-devel (git-deb6dd6 oneiric-oibaf-ppa) OpenGL shading language version string: 1.20 Driver: R600G GPU class: R600 OpenGL version: 2.1 GLSL version: 1.20 Mesa version: 7.12 X server version: 1.10.4 Linux kernel version: 3.2 Direct rendering: yes Requires strict binding: no GLSL shaders: yes Texture NPOT support: yes
I did more testing and found out that these artifacts appear when using "scale in" effect and "accurate" or "smooth" scale method. When using "scale in" effect and "crisp" scale method these artifacts doesn't appear.
I should add that this only happens with oxygen widget style. When plastic/qtcurve style is used, there are no artifacts above pop-up menus.
this is presumingly a result of the packed shadow texture layout and an invalid texture access position. I this remotely related to bug #282882
Git commit 7355a9ad14e24ca1eb4088430950bc88f03fb4de by Thomas Lübking. Committed on 08/02/2012 at 19:31. Pushed by luebking into branch 'KDE/4.8'. fix NPOT shadows a) fixes the texture offset calculation b) arranges he shadow pixmaps as border in the texture to avoid interpolation issues. Related: bug 280116, bug 282882, bug 293325 REVIEW: 103888 M +33 -53 kwin/scene_opengl.cpp http://commits.kde.org/kde-workspace/7355a9ad14e24ca1eb4088430950bc88f03fb4de
Git commit 4281fd09be344bfa99b0450eae384b49b55db152 by Thomas Lübking. Committed on 08/02/2012 at 19:31. Pushed by luebking into branch 'master'. fix NPOT shadows a) fixes the texture offset calculation b) arranges he shadow pixmaps as border in the texture to avoid interpolation issues. Related: bug 280116, bug 282882, bug 293325 REVIEW: 103888 M +33 -53 kwin/scene_opengl.cpp http://commits.kde.org/kde-workspace/4281fd09be344bfa99b0450eae384b49b55db152
I can confirm that this bug is now fixed for me. Thank you Thomas.
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