fast cone-cone-intersection

Hi everyone,

I searched the net but did not find much usefull stuff, so I ask you guys if anybody has some knowledge about calculating if two cones intersect or not.
I want to speed up my shadow volumes and so I start by calculating a cone from the light position and bounding sphere of an object and check if it intersects the bounding sphere of the frustum. If it does I want to check if the objects ‘shadow cone’ intersects the frustum-cone and if it does I can check against the frustum itself by using cone-plane-intersections.
It is just the cone-cone-intersection that is missing and of course it should be faster than checking the cone against the frustum because else there is no point in using it.
I hope somebody can help me.

I could do it for you. Send me an email at

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