I'm pretty sure at some point I had seen the ability in Chipmunk to define shape classes (cpShapeClass?) or possibly collision classes for the purpose of NOT receiving collision callbacks for shapes within the same shape/collision class. At the time, I didn't see the need for this, but now see I am constantly getting callbacks from overlapping static shapes in my game which I am routing to a one-line (return 0) callback, but nonetheless am incurring the overhead of the calls. Now that I'm looking for the information again, I can't find it either in the forums or in the documentaion.
Could someone please point me to info on how to define shapes into a common class so I will not receive callbacks on their collisions?
Thanks very much!