[SDL] Re: NV 0.9.6 and SDL windowed GL

Sylvain.Hellegouarch sylvain.hellegouarch at etud.univ-ubs.fr
Thu Jan 25 03:12:31 PST 2001


David Bateman wrote:
> 
> I built a copy of SDL that doesn't use dlopen(), but I still get "clip_lock:
> timed out [5]" messages. If for some bizarre reason someone wants a patch for
> this build, email me and I'll send you one.
> 
> Strangely, after upgrading my window manager this problem only manifests
> itself every tenth time or so. This is good enough for me to get on with
> some development, so I'll send a report to NVIDIA and hope their next driver
> release fixes things.
> 
> David.
> 
> David Bateman wrote:
> >
> > It would appear that this *is* an SMP-related problem.
> >
> > I build a new kernel using the same configuration as my current kernel except
> > for disabling SMP, rebooted in single-processor mode, rebuild the NVIDIA
> > kernel driver, and SDL apps started immediately. Rebooted using the SMP
> > kernel; 30 second delay when starting SDL apps.
> >
> > Looking at the NVIDIA driver FAQ, item 6.4.8 "OpenGL and dlopen()" says there
> > are problems with applications that use dlopen() to load the OpenGL library.
> > SDL uses this method, whereas GLUT (which works fine) does not. It doesn't
> > mention SMP in this item, however, which implies that this can happen on
> > single-processor machines as well. YMMV, I suppose...
> >
> > I'll try to modify a copy of SDL to not use dlopen() and see if it works
> > around the problem.
> >
> > David.
> >
> > David Bateman wrote:
> > >
> > > I also see this; there's almost always a 20-30 second delay between starting
> > > an SDL app and the window appearing. The rendering is fully accelerated once
> > > it does appear, though. Other windowed OpenGL apps start immediately, and Q3A
> > > works perfectly. The "clip_lock" message is also present in my
> > > /var/log/XFree86.0.log file after this occurs.
> > >
> > > I've just upgraded to Xfree86 4.0.2 (completely new /usr/X11R6 tree with the
> > > default libGL libraries removed) and the NVIDIA 0.9-6 drivers. To try and fix
> > > this I've done a fresh build of SDL 1.1.7 (previously had 1.1.2), built the
> > > lastest bintools from source, rebuilt the NVIDIA kernel module and rebooted (I
> > > thought it might be an SMP problem), but with no improvement.
> > >
> > > I'll see if I can deduce what SDL does differently to GLUT when opening an
> > > OpenGL window. I'm unsure whether to pester NVIDIA about this yet; it does
> > > seem to only affect SDL apps...
> > >
> > > Regards,
> > >
> > > David.
> > >
> > > Mark B. Allan wrote:
> > > >  With SDL 1.1.7 and the latest NVIDIA 0.9.6 drivers, whenever I try to
> > > > open a windowed GL context, my machine completely locks for about 5
> > > > seconds, then the window opens and the app behaves normally. X prints
> > > > out this info:
> > > >
> > > > (II) [GLX]: clip_lock: timed out [5]
> > > >
> > > > If the SDL app is started full screen, there's no problem (tested with
> > > > Chromium B.S.U. and glTron).
> > > >
> > > >  This behavior does not occur with GLUT, the Qt GL extension, or with
> > > > Q3.
> > > >
> > > >  Any ideas?
> > > >
> > > > Cheers,
> > > > Mark

It's really sad that NVidia doesn't give to opensource community their
cards spec. Because their releases aren't really great most of the time
and we have to wait so much time between two of them.

I got a Mandrake 7.2 systeme with NVidia 0.9.6 and SDL 1.1.7, and no OGL
works fine (even some little pseudo code i write), all my pc freezes and
i have to reboot !

Crap..






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