Chipmunk Physics

I want a static arc shape （portion of circle), but I cannot find how to do that in document, any idea?

Thanks

You can't. The best you can do is approximate it with lots of faces on a polygon or line segments.

Just curious if anyone has any insight on why simulating an arc shape would be hard. It "seems" easy enough: recognize as a circle but with extra checks against angle and distance (I realize this functionality is not in chipmunk... yet); anyone?

1) Create a cpCircleShape
2) Create your own collision callback in which you return 1 only when the collision normal is contained in the arc

cpCollFunc contains all the informations you need.