import java.applet.Applet;
import java.awt.*;

public final class Mandel extends Applet {
  private static final int MAX = 32;

  public void paint(Graphics g) {
    Dimension size = getSize();
    for (int y = 0; y < size.height; y++) {
      for (int x = 0; x < size.width; x++) {
        // squeeze (x, y) to the proper interval
        double dx = 2.5 * x / size.width - 2.0;
        double dy = 1.25 - 2.5 * y / size.height;
        int value = mandel(dx, dy); // compute value
        value = value * 255 / MAX; // stretch to 0-255
        g.setColor(new Color(value, value, value));
        g.drawLine(x, y, x, y); // draw point
      }
    }
  }

  private int mandel(double px, double py) {
    int value = 0;
    double zx = 0.0, zy = 0.0, zx2 = 0.0, zy2 = 0.0;
    while (value < MAX && zx2 + zy2 < 4.0) {
      zy = 2.0 * zx * zy + py;
      zx = zx2 - zy2 + px;
      zx2 = zx * zx;
      zy2 = zy * zy;
      value++;
    }
    return MAX - value;
  }
}