My engine have a bsp collision. 3 spheres collision with a 1500 face sccene run to 20 fps on my 1400 mhz with a radeon 7200.. If the ball intersect with the bounding box of the back node, check the collision with the back node and its childs... same thing for front. fps climb to 70-80.. Its similar to octree processing. Fantasio

Test it on your own computer, you''ll see...

Because of my poor font system, fps droped down...
When there are nothing to write to screen fps climb to 110-200..

http://membres.lycos.fr/fantasiiio

Give me your comments..