collision table: broadphaseLayer pairs. Index i*broadphaseLayers+j indicates if broadphase layer i collides with broadphase layer j
collision table: objectLayer pairs. Index i*objectLayers+j indicates if layer i collides with layer j
number of object layers
mapping from objectLayer to broadphaseLayer
collision table: objectLayer vs broadphaseLayer. Index i*broadphaseLayers+j indicates if object layer i collides with broadphase layer j
number of broadphase layers