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

public class model3D extends Applet implements Runnable {
  public Point left_origin = null;
  public Point right_origin = null;
  Triplet left_points = null;
  Triplet right_points = null;
  Thread kicker = null;
  boolean initialized=false;
  ExCanvas left, right;
  Modeler pad;
  boolean wait_for_left_org = true;
  boolean wait_for_right_org = true;
  boolean wait_for_right = true;
  boolean wait_for_left = true;
  int temp_px = 0;
  int temp_py = 0;
  int xa = -40;
  int xb = 40;
  int plane = 1000;
  int iodis = 20;
  int org_xl = 0;
  int org_xr = 0;
  int org_y = 0;
  Image i_left;
  Image i_right;
  Image point;
  Image highlight;
  Image origin;


  public void start() {
    if (kicker==null) {
      kicker=new Thread(this);
    }
    kicker.start();
  }


  public void run() {
    if (!initialized) {
      MediaTracker tracker = new MediaTracker(this);
      i_left = getImage(getDocumentBase(), "toy-left.gif");
      tracker.addImage(i_left, 0);
      i_right = getImage(getDocumentBase(), "toy-right.gif");
      tracker.addImage(i_right, 0);
      origin = getImage(getDocumentBase(), "origin.gif");
      tracker.addImage(origin, 0);
      point = getImage(getDocumentBase(), "point.gif");
      tracker.addImage(point, 0);
      highlight = getImage(getDocumentBase(), "point-select.gif");
      tracker.addImage(highlight, 0);
      try { tracker.waitForID(0); } catch (InterruptedException e) {}
      left = new ExCanvas(i_left, origin, point, highlight, this);
      right = new ExCanvas(i_right, origin, point, highlight, this);
      pad = new Modeler();
      initialized=true;
    }
    left = new ExCanvas(i_left, origin, point, highlight, this);
    right = new ExCanvas(i_right, origin, point, highlight, this);
    pad = new Modeler();
    add(left);
    add(right);
    add(pad);
    layout();
  }  


  public void deliver_point(ExCanvas caller, int mx, int my) {
    if (caller==left) {
      if (wait_for_right_org) {
	wait_for_left_org = false;
	temp_px = mx;
	temp_py = my;
      } else if (wait_for_left_org) {
	wait_for_left_org = false;
	left.getPoints();
	right.getPoints();
	pad.setOrigin(0, 0);
	org_xl = mx;
	org_xr = temp_px;
	org_y = my;
      } else if (wait_for_right) {
	wait_for_left = false;
	temp_px = mx;
	temp_py = my;
      } else {
	addPoint(pad, mx-org_xl, temp_px-org_xr, my-org_y);
	wait_for_left=true;
	wait_for_right=true;
	left.getPoints();
	right.getPoints();	
      }     
    }
    else {
      if (wait_for_left_org) {
	wait_for_right_org = false;
	temp_px = mx;
	temp_py = my;
      } else if (wait_for_right_org) {
	wait_for_right_org = false;
	left.getPoints();
	right.getPoints();
	pad.setOrigin(0, 0);
	org_xl = temp_px;
	org_xr = mx;
	org_y = temp_py;
      } else if (wait_for_left) {
	wait_for_right = false;
	temp_px = mx;
	temp_py = my;
      } else {
	addPoint(pad, temp_px-org_xl, mx-org_xr, my-org_y);
	wait_for_left=true;
	wait_for_right=true;
	left.getPoints();
	right.getPoints();	
      }
    }
    if (wait_for_left&&wait_for_right) {
      pad.repaint();
    }
  }

  public void addPoint(Modeler m, int xf, int xs, int my) {
    double m1 = ((double) plane) / ((double)(xf+iodis));
    double b1 = -m1*((double) xf);
    double m2 = ((double) plane) / ((double)(xs-iodis));
    double b2 = -m2*((double) xs);
    double d = -m2 + m1;
    double new_x = (b2-b1)/d;
    double new_z = (-b1*m2+b2*m1)/d;
    //System.out.println(xf+"   "+xs+"   "+my+"  :    "+new_x+"    "+my+"   "+new_z+" :  "+m1+"   "+b1+"   "+m2+"   "+b2);
    m.addPoint((int) new_x, my, (int) new_z);
  }


  public void stop() {
    remove(left);
    remove(right);
    remove(pad);
    wait_for_left_org = true;
    wait_for_right_org = true;
    wait_for_right = true;
    wait_for_left = true;
    if (kicker!=null) {
      if (kicker.isAlive()) {kicker.stop();}
      kicker = null;
    }
  }
  

  public void update(Graphics g) {
    paint(g);
  }

  public void paint(Graphics g) {
    if (!initialized) {
      g.drawString("Loading images... Please wait...", size().width/2-75, size().height/2);
    }
    else {
      super.paint(g);
    }
  }


  public void layout() {
    super.layout();
    if (left!=null && right!=null) {
      left.layout();
      right.layout();
    }
  }

  
}