KDE 4.4.0 and composite

Duncan 1i5t5.duncan at cox.net
Thu Feb 11 09:50:55 GMT 2010

David posted on Thu, 11 Feb 2010 05:53:58 +0100 as excerpted:

> Hi there, I'm trying to enable composite through openGL in KDE 4.4.0,
> but it only works in XRender mode.
> When I try to switch it to OpenGL mode, it says someting about an error
> and it disables again.

You didn't give anything like enough information.  "someting about an 
error" isn't a sufficient error description, for instance, and OpenGL is  
graphics, so information about your xorg version, the graphics chip brand 
and model, the xorg graphics driver (servantware or free/native xorg makes 
a difference too) and version, the kernel version and graphics related 
config (give that I see from another post your running Gentoo, so 
configure your own kernel, this would include whether you're running KMS, 
built-in kernel DRM or separate, framebuffer mode and which one there or 
just vgacon if not kms, etc), etc. 

FWIW, I run Gentoo as well.  I haven't upgraded my (32-bit gentoo/~x86 
Intel Atom and chipset) netbook yet, but I don't have the problem on my 
~amd64 with a Radeon 4650 card (agp not pci-e), running partially X 
overlay including direct git xorg radeon driver, since the freedomware 
support for the r700 series cards is new enough they don't have a released 
driver with it yet.  I'm running KMS on it, with now, a 2.6.33-rc-plus 
kernel (direct from Linus' git tree), with support MUCH improved from 
2.6.32, where OpenGL worked but was buggy.

Until recently, however, I was running an old Radeon 9200, which for years 
was about the top of the line with full freedomware driver support (I 
don't do servantware drivers, see sig).  It did OpenGL, but the OpenGL 
support was limited to overall resolutions under 2048 either direction.  
Since I'm running dual 1920x1200 LCDs stacked for 1920x2400, and before 
that was running dual 1600x1200 CRTs so 2400 vertical there as well, that 
limited my OpenGL support to the top 2048 px, leaving 352 without OpenGL.  
KDE4 doesn't handle that well (crashes) so once they added the 
functionality tests, it disabled OpenGL and left me with XRender/Composite 
only support.  Once I figured out how to configure things to get 
reasonable speed and what effects worked and which ones required OpenGL, 
that wasn't /too/ bad, all things considered, but it would have been much 
/better/ had there been some indication of which effects needed OpenGL and 
which didn't -- disabling/dimming the ones that needed OpenGL so they 
couldn't be selected if it was off, for instance.  Matter of fact, that 
was one of the big beefs I had with kde4, that it did /not/ give any 
indication of what effects would actually work in XRender/Composite-only 

Anyway, there's a checkbox available and you can choose to disable the kde 
OpenGL compatibility tests and force OpenGL on if you want to try it, but 
be aware that it's likely to crash if you do.  I tried it, then had to 
edit my xorg.conf to turn OpenGL off there, before I could get back into 
KDE to turn it off again, as otherwise I couldn't get to the dialog to 
turn it off.  (Of course, I could have tried to find it in my user config 
and disable it by editing the config file directly, too, but I knew where 
my xorg.conf was and I didn't know where exactly kde stored it in my kde 
user config, so it was easier to disable it in xorg.conf.)  So be prepared 
to do that before turning it on to try it, as chances are kde is disabling 
it for a reason.

Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman

This message is from the kde mailing list.
Account management:  https://mail.kde.org/mailman/listinfo/kde.
Archives: http://lists.kde.org/.
More info: http://www.kde.org/faq.html.

More information about the kde mailing list