import java.awt.*;
import java.awt.image.*;
import java.awt.geom.*;
import javax.swing.*;
import java.util.Random;

public class Plotter extends JComponent implements Runnable
{

  int imageWidth, imageHeight;

  double xLowerLeft, yLowerLeft, xUpperRight, yUpperRight;
  double pixelWidth, pixelHeight, invPixelWidth, invPixelHeight;
  double[] pt = new double[2];
  double posX, posY;
  double vertex0X, vertex0Y, vertex1X, vertex1Y, vertex2X, vertex2Y,
  vertex3X, vertex3Y, vertex4X, vertex4Y, vertex5X, vertex5Y, vertex6X,
  vertex6Y, vertex7X, vertex7Y;

  Random randNumGen = new Random(5);
  
  BufferedImage bufImage;
  Graphics2D bufImageGraphic;

  public Plotter(int w, int h, double xLL, double yLL, double xUR,
                 double yUR) 
  {
    posX = 0.0; posY = 0.8;
    pt[0] = posX; pt[1] = posY;
    vertex0X = vertex0Y = 0; 
    vertex1X = 1; vertex1Y = 0; 
    vertex2X = vertex2Y = 1;
    vertex3X = 0; vertex3Y = 1;
    imageWidth = w; imageHeight = h;
    xLowerLeft =  xLL; yLowerLeft =  yLL;
    xUpperRight = xUR; yUpperRight = yUR;
  	
    pixelWidth  = (xUR - xLL)/((double)w); 
    invPixelWidth  = ((double)w)/(xUR - xLL);
    pixelHeight = (yUR - yLL)/((double)h); 
    invPixelHeight = ((double)h)/(yUR - yLL);
  	
    System.out.println(imageWidth + "     " + imageHeight);
    System.out.println(pixelWidth + "     " + pixelHeight);
  
    bufImage = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
    bufImageGraphic = bufImage.createGraphics( );
    bufImageGraphic.setPaint(Color.white);
    //bufImageGraphic.setPaint(Color.black);
    bufImageGraphic.fillRect(0, 0, w, h);

    AffineTransform at = new AffineTransform(invPixelWidth, 
                                             0, 0, -invPixelHeight,
                                             -invPixelWidth*xLL, 
                                             invPixelHeight*yUR      
                                            );
    bufImageGraphic.setTransform(at);

    Thread t = new Thread(this);
    t.start(  );
  }

  public void timeStep( )
  {
    bufImageGraphic.setPaint(Color.blue);
    Rectangle2D p = new Rectangle2D.Double(pt[0], pt[1],
                                           pixelWidth/1.0, 
                                           pixelHeight/1.0); 
    bufImageGraphic.fill(p);
    pt = Sierpinski(pt);
  }

  public void run( ) 
  {
    try 
    { 
      //while (true)
      for(int i = 0; i < 5000; ++i)
      { //Loopbody:
        timeStep( ); 
        repaint( );
        Thread.sleep(0);
      }
    }
    catch (InterruptedException ie) {} 
  }

  public void paint(Graphics g) 
  {
    Graphics2D g2 = (Graphics2D)g;
    g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                        RenderingHints.VALUE_ANTIALIAS_OFF);
    //g2.setPaint(Color.blue);
    //g2.drawImage(image, imageX, imageY, this);
    g2.drawImage(bufImage, 0, 0, this);
  }

  public double[] Sierpinski(double[] pt)
  {
    int target = Math.abs(randNumGen.nextInt( )) % 4;
    double[] q = new double[2];
    switch (target) 
    {
      //case 0 : q[0] = pt[0]/2.0 + vertex0X/2.0; q[1] = pt[1]/2.0
      //+ vertex0Y/2.0; break;
      //case 1 : q[0] = pt[0]/2.0 + vertex1X/2.0; q[1] = pt[1]/2.0 +
      //vertex1Y/2.0; break;
      //case 2 : q[0] = pt[0]/2.0 + vertex2X/2.0; q[1] = pt[1]/2.0
      //+ vertex2Y/2.0; break;
      case 0 : q[0] = pt[0]/3.0 + (2.0*vertex0X)/3.0; 
               q[1] = pt[1]/3.0 + (2.0*vertex0Y)/3.0; break;
      case 1 : q[0] = pt[0]/3.0 + (2.0*vertex1X)/3.0; 
               q[1] = pt[1]/3.0 + (2.0*vertex1Y)/3.0; break;
      case 2 : q[0] = pt[0]/3.0 + (2.0*vertex2X)/3.0; 
               q[1] = pt[1]/3.0 + (2.0*vertex2Y)/3.0; break;
      case 3 : q[0] = pt[0]/3.0 + (2.0*vertex3X)/3.0; 
               q[1] = pt[1]/3.0 + (2.0*vertex3Y)/3.0; break; 
    }
    return q;
  }


  public static void main(String[] args) 
  {
    JFrame frame = new JFrame("Plotter");
    frame.setBackground(Color.white);
    Plotter plot = new Plotter(700, 700, -0.1, -0.1, 1.1, 1.1);
    //Plotter plot = new Plotter(700, 700, -2, -1.5, 1, 1.5);
    //Plotter plot = new Plotter(700, 700, 0, 0, 700, 700);
    frame.getContentPane( ).add(plot);
    frame.setSize(700, 700);
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    frame.setVisible(true);
  }

}