import java.awt.*;
import java.applet.*;
public class ConnectApplet extends Applet
implements Runnable {
Point current;
Point[] p=new Point[3];
Thread animation;
int w,h;
Image pictureImage;
Graphics picture;
public void init() {
w=size().width; h=size().height;
pictureImage=createImage(w,h);
picture=pictureImage.getGraphics();
p[0]=new Point(w/2,100);
p[1]=new Point(w/2+70,170);
p[2]=new Point(w/2-70,170);
current=p[0];
}
public void start() {
animation=new Thread(this);
animation.start();
}
public void stop() { animation=null; }
public void run() {
while (animation==Thread.currentThread()) {
updatePicture();
repaint();
try {Thread.sleep(20);} catch (Exception e) {}
}/v2/img/enterproject.gif
}
public void update(Graphics g) { paint(g); }
public synchronized void paint(Graphics g) {
g.drawImage(pictureImage,0,0,null);
}
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// key: code in gray makes the program run.
// code in black draws the picture.
public boolean mouseDown(Event e, int x, int y) {
int shortest=Integer.MAX_VALUE;
for (int i=0; i<p.length; i++) {
int d2=(p[i].x-x)*(p[i].x-x)+
(p[i].y-y)*(p[i].y-y);
if (d2<=shortest) {
current=p[i];
shortest=d2;
}
}
return mouseDrag(e,x,y);
}
public boolean mouseDrag(Event e, int x, int y) {
current.x=x; current.y=y; return true;
}
synchronized void updatePicture() {
for (int i=0; i<5000; i++) {
int x=(int)(w*Math.random());
int y=(int)(h*Math.random());
long a1=f(p[0],p[1],x,y),
a2=f(p[1],p[2],x,y),
a3=f(p[2],p[0],x,y);
picture.setColor(
(int)(a1*a2*a3)>0 ? a1*a2>0 && a2*a3>0 ?
Color.white : Color.gray : Color.black);
picture.drawLine(x,y,x,y);
}
}
long f(Point p1, Point p2, int x, int y) {
return ((p1.x-x)*(p2.y-y)-(p1.y-y)*(p2.x-x))/13;
}
}
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