// Example using a FOR loop to chromakey a sprite onto a background multiple times
// to give the appearnce of motion.
//
// Jay Summet - Georgia Tech
// Released to the public domain: Aug 2009
//

import java.awt.Color;

public class PictureAnimationExample {
 
  
  public static void main( String [] args ) {
    
    // Ask the user to pick a background. "Beach.jpg" or "Jungle.jpg" are good choices
    String myBackground = FileChooser.pickAFile();
      
    // p2Show is shown on-screen. p is used to store the unmodified background
    // and is copied (composed) on top of p2Show every time so that the sprite
    // will have a fresh background to be chromakeyed onto.
    Picture p2show = new Picture(myBackground);
    Picture p = new Picture(myBackground);
    
    // The following line will only work correctly if you have ALREADY set the
    // default Media Path using a command such as:
    // FileChooser.setMediaPath( FileChooser.pickADirectory() );
    Picture sprite = new Picture("mRight.jpg");
    // Another bluescreened background to try is dogSide.jpg
    
    // Show the background.
    p2show.show();
    
    // Load a pixel at 0,0 from the sprite picture and get it's color.
    // Use that color as the blue screen value.
    Pixel myPixel = sprite.getPixel(0,0);
    Color myColor = myPixel.getColor();
    
    System.out.println("Color at 0,0 is:" + myColor);
    
   
    int stepSize = p.getWidth() / 10;
    
    for(int i = 0; i < p.getWidth(); i = i + stepSize ) {
      sprite.chromakey( p2show, myColor, 50, i,0);
      p2show.repaint();
      
      // Compose the unmodified background back onto the drawing window
      // to get it ready to chromakey the sprite onto a fresh background
      p.compose(p2show,0,0);
     
     
    } // end for
    
  } // End of main
  
  
  
} // end of class Example