This directory contains various graphics hacks that requre OpenGL.  These are
independent from the xscreensaver program (in the ../../driver/ directory)
but some of them use the utility functions found in the ../../utils/ directory.

If you have compilation problems, check the parameters in ../../config.h.

If you're looking for a free implementation of the OpenGL library, 
check out <http://www.mesa3d.org/>.  For general OpenGL info, see
<http://www.opengl.org/>.