Physics help - one object inside other

Hey dudes I have a physics question:

I want to create 2 physic objects and put one inside the other and still to be influenced by each other.

example file here:

http://dl.dropbox.com/u/6070534/Physics_help.capx

As seen in the preview file

Variant A is pretty ready for the tweak of yours

Variant B is how I solved it so far...open the "set collision polygon" of the Black square to see the trick

I adjusted the polygon shape of the big black square to fake a hole in there.

Only thing I want to avoid is the number of the points in the polygonal colision shape....which might increase rapidly when using some round shapes

Feel free to comment

Cheers

pretty smart way of doing it, i think you got the best solution, a little improvement could be if we could merge points and i also hope for a way of setting a circle collision mask per frame, i think it uses an optimised calculation instead of just drawn out points

vtrix: this option is already available in the properties of the physic behavior : "Collision mask" - "Circle"

yes but i mean per frame, like you can select box collision per frame