Thanks Peter,
I use floats for all my OpenGL stuff, so it must be an issue with unprototyped float procs. I found literal floats were okay but float variable params were not, so I will see if there is a quick fix.
You have an interesting demo, as it shows the problems that arise when alpha is enabled. Objects furthest away from the viewer must be rendered first, otherwise they will mask out objects which are nearer to you in the scene.
Charles
