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=== doublebufferflag === tksurfer can read a flag which controls rendering. Setting that flag has been known to fix the sliver problem. To do this, in csh: {{{ setenv doublebufferflag 1 }}} In bash: {{{ export doublebufferflag=1 }}} Then start tksurfer. === VirtualGL === [[http://www.virtualgl.org/|The VirtualGL project]] is software that would be appropriate if your sliver problem appears when using a VNC connection, where often its the case that the local OpenGL renderer (for instance, on your laptop) doesnt fully support GLX. So you would download and install VirtualGL on your server (your sysadmin would do this), then you would run ssh or vnc from your client computer to the application server, then run: {{{ /opt/VirtualGL/bin/vglrun tksurfer bert lh inflated }}} === Override native graphics libraries === It might be the case that the graphics libraries installed when the Nvidia or ATI card is installed overwrites the natively installed drivers, that is, overwrites libGL.so.1.2 from Mesa that comes with RedHat. A solution at the NMR Center is to keep a copy of those libs elsewhere prior to conducting any driver update, so that those drivers can be used via LD_LIBRARY_PATH later if the newly installed drivers fail in some circumstance (typically when used in a VNC situation). === VirtualBox === You can run a virtual machine that runs freesurfer. It is the VirtualBox version of freesurfer available from the [[http://surfer.nmr.mgh.harvard.edu/fswiki/Download|freesurfer download site]]. See the README associated with it for installation instructions. |
Tksurfer display problems and solutions
The surface display app 'tksurfer' is an X11-app making use of OpenGL for graphics rendering. The complexity of this sort app is described in detail here.
The most common problem encountered in using tksurfer for the first time on a system is the 'sliver' problem, where just a 'sliver' of the surface is displayed, as shown in the bottom-left of this picture:
There are a few potential solutions you can try to overcome this problem:
NVidia driver update
If your system has an Nvidia graphics driver, then updating this to the latest version often times fixes the problem. To do this:
su root /sbin/init 3 /usr/bin/nvidia-installer --update
Follow the instructions of the installer
doublebufferflag
tksurfer can read a flag which controls rendering. Setting that flag has been known to fix the sliver problem. To do this, in csh:
setenv doublebufferflag 1
In bash:
export doublebufferflag=1
Then start tksurfer.
VirtualGL
The VirtualGL project is software that would be appropriate if your sliver problem appears when using a VNC connection, where often its the case that the local OpenGL renderer (for instance, on your laptop) doesnt fully support GLX. So you would download and install VirtualGL on your server (your sysadmin would do this), then you would run ssh or vnc from your client computer to the application server, then run:
/opt/VirtualGL/bin/vglrun tksurfer bert lh inflated
Override native graphics libraries
It might be the case that the graphics libraries installed when the Nvidia or ATI card is installed overwrites the natively installed drivers, that is, overwrites libGL.so.1.2 from Mesa that comes with RedHat. A solution at the NMR Center is to keep a copy of those libs elsewhere prior to conducting any driver update, so that those drivers can be used via LD_LIBRARY_PATH later if the newly installed drivers fail in some circumstance (typically when used in a VNC situation).
VirtualBox
You can run a virtual machine that runs freesurfer. It is the VirtualBox version of freesurfer available from the freesurfer download site. See the README associated with it for installation instructions.