[vtkusers] Building vtk, OSMesa not picked up correctly.

[Toby White]

Building vtk from the CVS sources of Wednesday, using cmake-1.0;
under linux, with Mesa-3.4.2 form XFree86-4.1.0.

Specifying all the correct library locations in cmake, it generates 
makefiles in each directory, however, under Rendering only, it does
not replace ${OSMESA_LIBRARY} with -lOSMesa. This results in 
the libvtkRendering* libraries not being linked against OSMesa, and
thus not working properly.

Editing the makefile by hand, and recompiling makes everything hunky-dory, 
and I have a working copy of the library. But everytime cmake is run again, 
it makes the same mistake.

Oddly, in Rendering/Testing, the Makefiles have both ${OSMESA_LIBRARY}
and -lOSMesa. Something very strange going on there.

Anyway - I don't know if this is a cmake problem, or a vtk one. I don't
know enough about either project to know where to look to fix this 
properly.

Toby