// Learning Processing
  // Daniel Shiffman
  // http://www.learningprocessing.com
  
  // Example 10-3: Bouncing ball with intersection
  
  // Two ball variables
  Ball ball1;
  Ball ball2;
  
  void setup() {
    size(400,400);
    smooth();
    
    // Initialize balls
    ball1 = new Ball(64);
    ball2 = new Ball(32);
  }
  
  void draw() {
    background(255);
    // Move and display balls
    ball1.move();
    ball2.move();
    
    if (ball1.intersect(ball2)) { // New! An object can have a function that takes another object as an argument. This is one way to have objects communicate. In this case they are checking to see if they intersect.
      ball1.highlight();
      ball2.highlight();
    }
    
    ball1.display();
    ball2.display();
  }