I have been working with rays and materials, and What I have been doing works great, except it cannot be compound, do to something about triangle meshes, so the objects can be ray casted after parenting, but not collided with.
So parented objects+triangle mesh =works with rays but not collisions
Objects parented with compound can’t be collided with properly.
I can not understand! Do you men Ray sensor?
raycast - polyproxy detects a polgon from a ray cast, but only works with triangle meshes,
however triangle meshes don’t support compound objects.
So if I use my system to parent a objects, it can be ray casted, but not impacted.
I think I can use a separate physics mesh, and a “ray mesh”, somehow. but I am still thinking about it…
ok… i don’t know anything about raycast. 
but what you say about have double mesh sounds good.
Ok, so, I think all of my problems could easily be solved, if someone set up object.RBJTarget
Right now I can get it to work,
A RBJ actuator is what I really need.
Anyone code C++ and C?
http://www.pasteall.org/blend/27269 - solution
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