// Mixing,  Evgeny Demidov,  28 Aug 2007

import java.awt.*;
import java.awt.image.*;
import java.awt.event.*;
import java.util.StringTokenizer;

public class @file extends java.applet.Applet implements MouseListener,
  KeyListener, ActionListener {
double Yc=.0, Xc=-.5, dx=6.283, dy=dx, R=.3,  K=1, Pi=Math.PI, Pi2=Pi*2;
int maxColor=3, N=1, w, h, w2, h2,  pixArr[];
Image img;             IndexColorModel RainbowColor;
Label     lbK, lbN, lbR;
TextField tfXY, tfK, tfN, tfR;
Button    btPl, btMn;

public void init() {
  String s=getParameter("XYmidDelCD"); if (s != null) {
    StringTokenizer st = new StringTokenizer(s);
    Xc = Double.valueOf(st.nextToken()).doubleValue();
    Yc = Double.valueOf(st.nextToken()).doubleValue();
    dx = Double.valueOf(st.nextToken()).doubleValue();
    dy = Double.valueOf(st.nextToken()).doubleValue();}
  s=getParameter("K"); if (s != null) K = Double.valueOf(s).doubleValue();
  s=getParameter("R"); if (s != null) R = Double.valueOf(s).doubleValue();
  s=getParameter("N"); if (s != null) N=Integer.parseInt(s);
  byte rColor[] = new byte[maxColor], bColor[] = new byte[maxColor],
       gColor[] = new byte[maxColor];
  bColor[1] = gColor[1] = 0; rColor[1] = (byte)255;
  rColor[2] = gColor[2] = 0; bColor[2] = (byte)255;
  rColor[0] = gColor[0] = bColor[0] = (byte)255;
  RainbowColor = new IndexColorModel( 8, maxColor, rColor,gColor,bColor);
  w = getSize().width;   h = getSize().height;
  w2 = w/2;  h2 = h/2;
  pixArr = new int[w*h];
  this.setLayout( new FlowLayout(FlowLayout.LEFT, 0, 0) );
  tfXY = new TextField( ""+(float)Xc+" "+(float)Yc+"; "+(float)dx+
    " "+(float)dy, 20);   add(tfXY);
  lbK = new Label("K", Label.RIGHT); add(lbK);
  tfK = new TextField( "" + K, 2);   add(tfK);
  tfK.addKeyListener(this);
  lbR = new Label("R", Label.RIGHT); add(lbR);
  tfR = new TextField( "" + R, 2);   add(tfR);
  tfR.addKeyListener(this);
  lbN = new Label("N", Label.RIGHT); add(lbN);
  tfN = new TextField( "" + N, 1);   add(tfN);
  tfN.addKeyListener(this);
  btPl = new Button("+"); btPl.addActionListener(this); add(btPl);
  btMn = new Button("-"); btMn.addActionListener(this); add(btMn);
  Draw();
  addMouseListener(this);
}

public void destroy() {  removeMouseListener(this); }
public void mouseClicked(MouseEvent e) {}      //1.1 event handling
public void mousePressed(MouseEvent e) {}
public void mouseEntered(MouseEvent e) {}
public void mouseExited(MouseEvent  e) {}

public void mouseReleased(MouseEvent e) {
  Xc = Xc+(e.getX()-w2)*dx/w;
  Yc = Yc-(e.getY()-h2)*dx/w;
  if (e.isControlDown()){
    dy *= 2.; if (!e.isShiftDown()) dx *= 2.;}
  else {
    dy /= 2.; if (!e.isShiftDown()) dx /= 2.;}
  tfXY.setText( ""+(float)Xc+" "+(float)Yc+"; "+(float)dx+" "+(float)dy);
  Draw();
  repaint();
}
public void actionPerformed(ActionEvent e){
  if ( e.getActionCommand().equals("+") ) N++;
    else N--;
  tfN.setText(""+N);
  Draw();
  repaint();
}
public void keyTyped(KeyEvent e) {}
public void keyPressed(KeyEvent e) {}
public void keyReleased(KeyEvent e) {
  final int keyEnter = 10;
  if (e.getKeyCode() == keyEnter) {
    try{
      K = Double.valueOf(tfK.getText()).doubleValue();
      R = Double.valueOf(tfR.getText()).doubleValue();
      N = Integer.parseInt(tfN.getText());
      Draw();
      repaint();
    }catch ( NumberFormatException ne) {}
  }
  e.consume();
}

public void paint(Graphics g) {
  g.drawImage(img, 0, 0, this);
}

public void Draw(){
  for (int p = h*w; p > 0;) pixArr[--p] = 0;
  int pix, ix,iy;
  pix = 0;
  double X,Y, Xo,Yo;
  for (iy=0; iy < h; iy++) {
   Yo = Yc + (h2-iy)*dy/h;
   for (ix=0; ix < w; ix++){
    Xo = X = Xc + (ix-w2)*dx/w;  Y = Yo;
     for(int i=N; i>0; i--){
       Y = Y + K*Math.sin(X);
       X = X + Y;
       while(X < -Pi) X += Pi2;
       while(X > Pi) X -= Pi2;
       }
     if((Math.abs(X) < R)&&(Math.abs(Y) < R)) pixArr[pix] = 2;
     X = Xo; Y = Yo;
     for(int i=N; i>0; i--){
       X = X - Y;
       Y = Y - K*Math.sin(X);
       while(X < -Pi) X += Pi2;
       while(X > Pi) X -= Pi2;}
     if((Math.abs(X) < R)&&(Math.abs(Y) < R)) pixArr[pix] = 1;
    pix++;}
  }
//System.out.println(""+Xc +"  "+Yc);
  img = createImage(new MemoryImageSource(w, h, RainbowColor, pixArr, 0, w));
}

}