A design decision which needs to be made is at what level of abstraction should the data be "fixed", i.e. not to be manipulated with the full power of CL. This is often a flexibility vs. efficiency tradeoff.
In my 3D CL system [0], I have so far kept all geometric data as naive CLOS classes as the intent of the system is to provide a sandbox for experimentation. I have thought of, perhaps one day, representing the geometry as a foreign library for efficient passing to the GPU.
