--- a/src/PhysicsObject.hh	Sun Dec 07 23:10:30 2008 +0000
+++ b/src/PhysicsObject.hh	Sun Dec 07 23:27:20 2008 +0000
@@ -154,7 +154,10 @@
     /**
      * Define object behaviour on collisions.
      */
-    virtual void onCollision (Vector collisionPoint) {}
+    virtual void onCollision (Vector collisionPoint, PhysicsObject *other) {}
+
+public:
+    PhysicsWorld &world;
 
     /**
      * Checks if it is possible for the object to be in the given
@@ -162,9 +165,6 @@
      */
     bool possibleLocation(Vector loc);
 
-public:
-    PhysicsWorld &world;
-
     /**
      * Get current object position.
      *