import java.applet.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;

public class Fragment extends Applet implements ActionListener, MouseListener, Runnable {


  volatile boolean stop = false;

  int itterations = 500;

  Thread theThread;
  Image im;
  int width = 400, height = 400;
  double xmin=-2, xmax=2, ymin=-2, ymax=2;
  int lastMinI=0;
  int[] data, colorData;
  MemoryImageSource imSource;
  public void init() {
    if (getParameter("itterations")!=null) {
      try {
        itterations = Integer.parseInt(getParameter("itterations"));
      }
      catch (NumberFormatException e) {
        System.out.println(e);
      }
    }
    setLayout(new BorderLayout());
    Button b = new Button("Start");
    b.addActionListener(this);
    addMouseListener(this);
    add(b, "South");
  }
  public void start() {
    //updateData();
  }
  public void stop() {
    if (theThread != null) theThread.stop();
  }
  public void destroy() {
    if (theThread != null) theThread.stop();
  }
  public void actionPerformed(ActionEvent e) {
    updateData();
  }
  public void mouseClicked(MouseEvent e) {
    //zoom(xmin+(xmax-xmin)*e.getX()/width, ymin+(ymax-ymin)*e.getY()/height, .25);
    //updateData();
    stop = true;
  }
  public void mousePressed(MouseEvent e) { }
  public void mouseReleased(MouseEvent e) { }
  public void mouseEntered(MouseEvent e) { }
  public void mouseExited(MouseEvent e) { }
  
  public void updateData() {
    if (theThread != null) {
      try {
        stop=true;
        Thread.yield();
        theThread.stop();
      }
      catch (Exception e) { System.out.println(e); }
    }
    try {
      colorData = new int[width*height];
      imSource = new MemoryImageSource(width, height, colorData, 0, width);
      imSource.setAnimated(true);
      im = createImage(imSource);
      repaint();
      theThread = new Thread(this);
      theThread.setDaemon(true);
      theThread.setPriority(Thread.currentThread().getPriority()-1);
      theThread.start();
    } catch (Exception ex) { ex.printStackTrace(); }
  }
  
  public void update(Graphics g) {
    paint(g);
  }
  public void paint(Graphics g) {
    g.drawImage(im, 0, 0, this);
    //System.out.println("painted "+im);
  }
  
  public void zoom(double zfact) {
    zoom((xmax+xmin)/2, (ymax+ymin)/2, zfact);
  }
  public void zoom(double x, double y, double zfact) {
    double dx = xmax-xmin, dy = ymax-ymin;
    dx *= zfact; dy *= zfact;
    xmin = x - dx/2; xmax = x + dx/2;
    ymin = y - dy/2; ymax = y + dy/2;
  }
  
  public void toRedOrange(int data[], int[] colorData) {
    //int[] colorData = new int[data.length];
    for(int i=0; i<data.length; i++) {
      if (data[i] == -1) colorData[i] = (255 << 24);
      else colorData[i] = (data[i] << 8) | (255 << 16) | (255 << 24);  // red & orange
    }
    //return colorData;
  }
  
  public void run() {
    stop=false;
    for(int i=0; i<itterations; i++) {
      if (data==null) data = getImageData(width, height);
      else data = fragment(data, width, height);
      if (i%25 == 0) {
        toRedOrange(data, colorData);
        imSource.newPixels();
        //System.out.println(i);
        //imSource = new MemoryImageSource(width, height, toRedOrange(data), 0, width);
        //im = createImage(imSource);
        //System.out.println("made image "+im);
        //repaint();
        try { Thread.sleep(100); } catch (Exception e) { }
      }
      if (stop) break;
    }
    System.out.println("done");
  }
  
  
  public int[] getImageData(int w, int h) {
    int[] data = new int[w*h];
    for(int i=0; i<data.length; i++) data[i] = 128;
    return data;
  }
  
  public int[] fragment(int[] data, int w, int h) {
    int x0=(int)(w*Math.random()), y0=(int)(h*Math.random());
    double ang = Math.random()*2*Math.PI;
    double m = Math.tan(ang);
    int dz;
    if (Math.random() < .5) dz=1;
    else dz=-1;
    for(int x=0; x<w; x++) {
      for(int y=0; y<h; y++) {
        if (y > (x0-x)*m) data[w*y+x]+=dz;
        else data[w*y+x]-=dz;
      }
    }
    return data;
  }
  
  
}