Hello,
The simple measure of enabling shading for a double click on the title bar has caused the loss of OpenGL compositing and I now have to use XRender. It seems to work well enough, but it surprised me that the change of title bar double click should cause such a problem. Changing it back or changing it to none hasn't made OpenGL compositing available again. If I try to enable it, I see a 'Sorry' message saying:

Failed to activate desktop effects using the given configuration options.
Settings will be reverted to their previous values.

Check your X configuration. You may also consider changing advanced options, especially changing the compositing type.

When I first noticed that compositing was disabled and I tried to re-enable it a notification popped up which said something like:

Another application is using the feature requested. Press Alt-Shift-F12 to disable it.

Pressing the key combination did nothing as far as I could tell.

My /etc/X11/xorg.conf is:

Code: Select all

Section "Monitor"
   Identifier   "Configured Monitor"
EndSection

Section "Screen"
   Identifier   "Default Screen"
   Monitor      "Configured Monitor"
   Device      "Configured Video Device"
   DefaultDepth   24
EndSection

Section "Module"
   Load   "glx"
EndSection

Section "Device"
   Identifier   "Configured Video Device"
   Driver   "nvidia"
   Option   "NoLogo"   "True"
EndSection
                                                                                 
Section "ServerFlags"
   Option "BlankTime"   "0"
   Option "StandbyTime" "0"
   Option "SuspendTime" "0"
   Option "OffTime"     "0"
   Option "DontZap" "false"
EndSection



When I enabled the title bar feature, compositing was disabled, although I didn't notice at the time, and any new window opened was maximised. I had to click the maximise button twice to restore my previous 'Special' setting. Not what I wanted, although double click shading worked. I then found I could not run some of the window setting dialogues. Clicking just did nothing. Eventually decide to re-boot and the shut down took much longer than usual.

I imagine the problem would be repeatable, though only the brave should test it.

kernel = Linux asus 2.6.38-5-lowlatency #32~ppa1-Ubuntu SMP PREEMPT
nvidia driver version = 270.29
Mint 10 KDE amd64 KDE 4.6

(I realise the kernel and graphics driver are non standard, but it had been working very well previously. Still does, but I'm partly reporting a possible bug and partly hoping to get OpenGL compositing back.)

Thanks.

Edited to add: Just tried 'sudo rm ~/.kde/share/config/plasma*' and now using 4.6.1, but still no OpenGL compositing.

Does OpenGL compositing work under a new user?

Thanks for the suggestion, but I don't seem to be able to log in as the new user I created. Root enforces a password change, but either doesn't accept keyboard input, doesn't switch to 'repeat new password' (or however it's phrased) or completely locks up if I convince it to accept input and click OK. Pointer still moves on screen, but clicking cancel, pressing escape or Ctrl-Alt-Delete repeatedly has no effect. Have to hard reset.

I've tried giving it a stupidly simple or very strong password, but I'm still forced to change it when I try to log in.

I always set up a real root user, but I never run his desktop environment.

I'll try, as root, to 'useradd' tomorrow.

I used 'adduser' instead.

All's well for the new user. OpenGL compositing was enabled by default, as was the nVidia driver, and I set title bar double click to Shade without any of the problems I mentioned. I can live with XRender compositing. Haven't noticed any difference really, but if anyone can think of a way to get OpenGL back - I'm happy to try anything.

Thanks again.

Under your old user, try removing the KWin configuration with KWin closed. It may be best to do this from a virtual terminal, or as follows in Konsole:

Code: Select all

kquitapp kwin
sleep 5s
rm $(kde4-config --localprefix)/share/config/kwinrc
kwin --replace &

That did it! Thank you.

I saved a copy of the kwinrc for comparison with the new one generated. The new one only had a couple of lines:

[Compositing]
OpenGLIsUnsafe=false

[Desktops]
Name_1=

But everything on my desktop appeared ~exactly as before and OpenGL compositing was set and working. The OpenGLIsSafe line =true in the old one, but I do remember trying to disable functionality checks while trying to get it back, without success.

Not sure if it could be relevant to what went wrong, but I initially had an outline of a panel near the middle of the desktop, which disappeared after a reboot or two. It looked roughly the size and shape of one I have on the right hand side. Anyway, all's well now.