/* File: AnimatedSquare.java
 *--------------------------
 * This program animates a square so that it moves from
 * the upper left corner of the window to the lower right
 * corner.
 */

import acm.graphics.*;
import acm.program.*;

public class AnimatedSquare extends GraphicsProgram {

   public void run() {
      GRect square = new GRect(0, 0, SQUARE_SIZE, SQUARE_SIZE);
      square.setFilled(true);
      add(square);
      double dx = (double)(getWidth() - SQUARE_SIZE) / N_STEPS;
      double dy = (double)(getHeight() - SQUARE_SIZE) / N_STEPS;
      for (int i = 0; i < N_STEPS; i++) {
         square.move(dx, dy);
         pause(PAUSE_TIME);
      }
   }

/* private constants */
   private static final int N_STEPS = 1000;
   private static final int PAUSE_TIME = 20; /* msec */
   private static final int SQUARE_SIZE = 50;
}