Is it possible to check which point is being touched?

Hello, guys. I'm coding with some primitive meshes such as sphere, cube, cylinder. For now, I'm planing about game like billiard. If I add force to specific mesh, the mesh checks which point is being touched and how many powers received. And the mesh goes to vector which is opposite vector of touch vector. As I know, in Unity, objects check only whether it is touched or not by OnTriggerEnter or OnCollisionEnter and so on, but there isn't any functions which I planned. Is anybody knows how to check which point is being touched in meshes? [If possible, I'd like to know absolute position in gameScene.] (if image doesn't show up, http://imgur.com/9U33mo9) THx for reading! [1]: http://imgur.com/9U33mo9