Switched it to allow for up to 100 test objects before you can't prove which object is which via instance count.

Ball.h

@@ -10,11 +10,16 @@ public:
 	Ball() : GraphicsObject(&Ball::SetX, this) // pointer to self (specific instance)
 		{
 			instance_num = ++instance_counter;
+			// NOTE(dev): don't go above 100, please, for the sake of the example.
+		}
+	void GetXFromPhysicsSimulation()
+		{
+			x = instance_num + ((rand() % 10) * 100); // move around by ten, but keep single digit
 		}
 	static void SetX(int &x, void *instance)
 		{
 			Ball *ball = static_cast<Ball*>(instance);
-			ball->x = ball->instance_num; // prove we're accessing the right one
+			ball->GetXFromPhysicsSimulation();
 			return;
 		}