【狼】unity3d collision获取碰撞的点的位置

           void OnCollisionEnter(Collision ctl)
  　　  {
            ContactPoint contact = ctl.contacts[];
            Quaternion rot = Quaternion.FromToRotation(Vector3.up, contact.normal);
            Vector3 pos = contact.point;
        }

pos 即为碰撞的点的位置