// Pressing the mouse stops and starts the sound
 public void mousePressed() {
   if (tone.isPlaying()) {
     tone.stop(); //   The sound can be stopped with the function stop().
   } else {
     tone.repeat();
   }
 }
  public void setup() {
    size(200, 200);
    // Start Sonia engine.
    Sonia.start(this);

    // Create a new sample object.
    tone = new Sample("tone.wav");

    // Loop the sound forever
    // (well, at least until stop() is called)
    tone.repeat();
    smooth();
  }