I assume you have more than 2 displays connected? In that case the demo is probably trying to display on the wrong displays. It is hard-coded to use screens 0 and 1, assuming a dual-display setup.
If i have to guess, your desktop monitor (with the dock and menu-bar etc.) is connected to
one GPU and shows up as screenid 0, whereas the two displays for stereo work are connected to the 2nd GPU and correspond to screens 1 and 2. In that case or similar cases, the hardcoded screenids 0 and 1 would try to open the left-eye window on your first GPU and the right-eye window on the 2nd GPU, which is a no-go.
Apparently, "the worlds most advanced operating system", driving "up to eight displays in the fastest Mac graphics ever" (<
http://www.apple.com/macpro/features/graphics.html>) (quote of the iPhone company), can't even share resources across different graphics cards, so whenever your 2 stereo display monitors are not attached to the same graphics card, it will bomb out with the "invalid share context" error message.
I really wonder why they advertise 8 display support if they still can't get simple dual-display operation right even in Snow Leopard -- not speaking of Leopard which was an utter disaster on NVidia cards and it took them over 14 months to fix that for Snow Leopard.
Test which screenids the command Screen('Screens') returns? Probably 0, 1 and 2?
Try if PerceptualVBLSyncTest([1,2], 10); works. It would try stereomode 10 on screens 1 and 2.
Then you'll need to change the hardcoded values in the demos to make them work. Unfortunately it gets difficult to automatically select the 2 out of n displays on a n > 2 display setup, so the demos need tweaking.
I hope that is the problem, because otherwise things get ugly. Let us know if this is the problem.
-mario
--- In psychtoolbox@yahoogroups.com, "philipmgrove" <philipmgrove@...> wrote:
>
> Thanks for your suggestions. I think I solved it by simply running DownloadPsychtoolbox after I put the downloaded SVN into my Matlab folder and added it to the path. Psychtoolbox is running fine but I am still unable to get my two cinema displays to work with the StereoDemo. The details are in my previous post on my stereo problems.
>
> Any suggestions would be welcome.
>
> Many thanks,
>
> Phil
>
> --- In psychtoolbox@yahoogroups.com, "Mario" <mario.kleiner@> wrote:
> >
> >
> >
> > The current Updater in 'beta' is hopefully updated to hopefully handle this, but that doesn't help you now because the updater needs an update first before it can update anything ;-)
> >
> > A simple workaround around these problems is to add the path which contains the svn executable to your Matlab path.
> >
> > e.g., if svn is stored in /usr/bin as /usr/bin/svn
> > you can simply add /usr/bin to Matlab's path, and our routines will find it.
> >
> > -mario
> >
> > --- In psychtoolbox@yahoogroups.com, "e_flister" <e_flister@> wrote:
> > >
> > > hm, i think that's where the premade binary installs. you might have to logout/login?
> > >
> > > you can see how it's trying to find the path here:
> > > http://svn.berlios.de/wsvn/osxptb/trunk/Psychtoolbox/PsychOneliners/GetSubversionPath.m
> > >
> > > since you don't necessarily have the latest version of this file, you might augment GetSubversionPath with wherever your install actually is (use 'which svn' in a terminal to find it).
> > >
> > > i don't see why we aren't using [a b] = system('which -a svn') though. but when i just tried it, i realized that matlab runs under an overridden PATH env (which does not include /usr/local/bin):
> > >
> > >
> > > >> [a b] = system('echo $PATH')
> > > a =
> > > 0
> > > b =
> > > /usr/bin:/bin:/usr/sbin:/sbin
> > >
> > >
> > > thus, the following doesn't see all of my svn installs, including my preferred one:
> > >
> > >
> > > >> [a b] = system('which -a svn')
> > > a =
> > > 0
> > > b =
> > > /usr/bin/svn
> > >
> > > that's lame.
> > > -e
> > >
> > > --- In psychtoolbox@yahoogroups.com, "philipmgrove" <philipmgrove@> wrote:
> > > >
> > > > I have been trying to install/update Psychtoolbox on a new Mac Pro running Snow Leopard. I copied the Psychtoolbox folder over from my Macbook Pro and have some functionality of the package. However, I can't seem to get the subversion client to work. I have downloaded it from the specified webpage, and installed it but I get the following error when I type UpdatePsychtoolbox.
> > > >
> > > > The Subversion client "svn" is not in its expected
> > > > location "/usr/local/bin/svn" on your disk. Please
> > > > download and install the most recent Subversion client from:
> > > > web http://metissian.com/projects/macosx/subversion/ -browser
> > > > and then run UpdatePsychtoolbox again.
> > > >
> > > > I have updated to Snow Leopard on my Macbook Pro as well, and my subversion client is out of date. I get the same error when I try to update on this machine as well.
> > > >
> > >
> >
>