46. The apparatus of claim 45, wherein for each occluder in said scene, normals representing occlusion volume are stored with said object by associating a linked list of bounding volume normals with each shape node in a scene graph.
46. The apparatus of claim 45, wherein for each occluder in said scene, normals representing occlusion volume are stored with said object by associating a linked list of bounding volume normals with each shape node in a scene graph. 47. The apparatus of claim 46, further comprising: a linked list of pointers to occluder nodes in said scene graph for locating occluders quickly.