With nvidia driver 177.70 and kde trunk the windows is not correctly repainted when switching between applications resulting in a badly looking screen. Here is an image when I switched from konqui to konversation. Depending on the situation, the desktop might look much uglier. Turning off desktop effects helps. http://andras.kdewebdev.org/other/desktopmess.png
Does the problem occur with the 173 driver? Also what graphics card do you have?
Geforce 7600GS, I will try 173 soon.
It happens with 173.14.05 as well.
I've never noticed this with my nvidia. Does Compiz work? If it is relatively recent, can you find the exact commit? Not much to do otherwise I'm afraid.
I see it to on two computers, both running openSUSE, one with self compiled KDE, the other using KDE 4.1.x packages from openSUSE, currently ""Version 4.1.2 (KDE 4.1.1 (KDE 4.1 >= 20080828)) "release 49.1"". This one has 173.14.12 and a Quadro NVS 140M. The bug usually happens on quick switch (alt-tab without selection menu or effect or clicking on the taskbar). Well, I don't exactly know when it appeared but IIRC there was a time when on IRC #kwin even the topic suggested to do something because kwin window switching is broken. It appeared around that time.
Tried with 177.76 and the openSUSE 4.1.1 packages, the bug is there. :(
Here is what I found: - trunk from 25th of August shows the problem - trunk from 20th of August does not show it Sorry, I did not have time (and won't have next week) to narrow the interval. But as I said the bug is present in 4.1.1 as well (in the openSUSE packages), so it is something that was backported.
Possible trunk commits between 20th and 25th August: Revision 852355 Apparently it is possible to switch compositing between starting and getting a zero-timeout timer. Revision 851742 Support for unredirecting fullscreen windows, i.e. games etc. can paint directly and not be slowed down by going through compositing. Turned on and no UI option in the naive hope that it won't cause any real problems. Maybe effects doing window previews should get API to suspend unredirect though. Revision 851667 Cache the result of XQueryTree(). Revision 850941 Make sure idling does not actually cause big load by a repeating quick timer caused by dynamically adjusting the next repaint when using vsync. Ideally there should be no idle ticks at all, somewhen later. BUG: 154270 CCBUG: 155694 Possible 4.1 branch commits between 20th and 25th August: Revision 850943 Make sure idling does not actually cause big load by a repeating quick timer caused by dynamically adjusting the next repaint when using vsync. Ideally there should be no idle ticks at all, somewhen later. As r850941/850943 is the only one that was backported if you can test at that revision and as well as one revision before that would be great as verification.
Revision 851667 Cache the result of XQueryTree(). This is the commit causing the problem. About the backport...if this wasn't backported in the kde svn, maybe the opensuse developers backported for their own package.
*** Bug 171827 has been marked as a duplicate of this bug. ***
Created attachment 27622 [details] kwin patch Does this patch help? It's very difficult for me to reproduce the problem.
On machine with intel graphics this seems to fix it, will try on nvidia when I get back home.
Works now on nvidia too.
r866605, I don't know why bugzilla didn't pick up the commit.
*** Bug 170498 has been marked as a duplicate of this bug. ***