pouët.net

http://developer.nvidia.com/object/robust_shadow_volumes.html

Beware of software patents tho (z-fail aka "carmack's reverse" comes to mind).

what about this ambient occlusion thingy then? what is up with that? is that shadows aswell?

Yes, but like ambient lighting is used to simulate world lighting from no specific lightsource, the ambient occlusion technique models shadows from the object itself. It's not a dynamic shadowing method, it's done as a preprocessing step and (usually) baked into the vertices.

anyone interested to give me a short explanation about this software patents stuff. i am outing myself to have no clue about what these discussions are about. i mean, yes i know patents but how and on which types of ideas they can be made and especially where... don't we have a political disussion about this topic right now? or am i mixing up stupid stuff :)
are these us patents even valid for europe?