FindModule for OpenGL and GLU.
This module sets the following variables:
- True, if the system has OpenGL.
- True, if the system has XMESA.
- True, if the system has GLU.
- Path to the OpenGL include directory.
- Paths to the OpenGL and GLU libraries.
If you want to use just GL you can use these values:
- Path to the OpenGL library.
- Path to the GLU library.
On OSX default to using the framework version of OpenGL. People will have to change the cache values of OPENGL_glu_LIBRARY and OPENGL_gl_LIBRARY to use OpenGL with X11 on OSX.