--- a/src/PhysicsObject.hh	Sat Dec 06 20:56:24 2008 +0000
+++ b/src/PhysicsObject.hh	Sat Dec 06 21:02:35 2008 +0000
@@ -34,6 +34,8 @@
     bool alive;
     bool shouldDelete;
 
+    PhysicsObject *pivot;
+
     PhysicsObject(PhysicsWorld &world, float mass, Vector position, 
                   Vector velocity, bool enabled = true);
     virtual ~PhysicsObject (void);
@@ -219,6 +221,16 @@
     bool removeIfDestroyed (void);
 
     /**
+     * Sets this object's pivot to the given value, which will then exert a force on this object
+     */
+    void setPivot (PhysicsObject *pivot);
+
+    /**
+     * Compute the force that this object (as a pivot) exerts on the given object
+     */
+    virtual float getPivotForce (PhysicsObject *bob);
+
+    /**
      * Update object in physics simulation.
      */
     virtual void tick (TimeMS tick_length);