[vtkusers] Off Screen Rendering for X11

[Glen Lehmann]

Due to the frequency of the off screen rendering topic I've made 
vtkXOpenGLOffScreenRenderWindow (a hack of John Shalf's 
vtkOpenGLOffscreenRenderWindow) for X11 systems available at 
http://www.imaging.robarts.ca/~glehmann/OffScreen/OffScreen.html 
<http://www.imaging.robarts.ca/%7Eglehmann/OffScreen/OffScreen.html>.  
This class is intended for X11 users who do not wish to build vtk with 
mangled mesa.  Please, check out the README before you download it.

Good luck,
Glen