Collision Detection For Objects Modelled ByCSG

Physically based computer animation has to deal with the problem of detecting collisions of moving objects and preventing solid objects from interpenetration. This paper discusses a method for detecting collisions among complex objects modelled with the constructive solid geometry paradigm. Bounding volumes in each node of the CSG tree are used to determine as soon as possible whether a collision is likely to occur. Pairs of primitives one of each object are determined whose bounds cover common space. Spatial subdivision is used to detect these candidate pairs which have to be tested for collision using a geometric approach. The geometry of the intersection region is used to determine the collision point and the time and type of contact which are required for collision response.