Animation test;
Animation a_box;
Animation an_ellipse;
BFont font;

void setup()
{
  size(400,100);
  font = loadFont("RotisSanSer.vlw.gz");
  textFont(font, 20); 
 
  a_box = new Animation(this, loadImage("image.gif"), 0,0, 20,20);
  a_box.setStep("BOX");
  a_box.showRectangle();
  
  an_ellipse = new Animation(this, loadImage("image.gif"), 0,0, 10,-40);
  an_ellipse.setStep("ELLIPSE");
  an_ellipse.showRectangle();
  
  test = new Animation(this, a_box, 100,40, 200,40);
  test.setDuration(10000);
  test.showRectangle();
}

void loop()
{
  background(127);
  
  if (test.currentPercentage() < 0.5)
    test.setAnimation(a_box);
  else
    test.setAnimation(an_ellipse);      
  test.draw();
  
  Animation current = test.animation(); // retrieve the nested animation.
  if (current == a_box)
    text("Inner animation is a box.", 25, 25);
  else
    text("Inner animation is an ellipse.", 25, 25);
  
}