/* Written by Nick Exner on 7/29/98     *
 * Free to distribute                   */

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

public class EstPi extends Applet {
Image backCliff;
Image volume;
Image offscreenImage;
Graphics offscreenGraphics;

int maxPoints=500;
int xspots[] = new int[maxPoints];
int yspots[] = new int[maxPoints];
int currspots=0, volPosition=244,prevX=0, prevY=0;
int volLevel=250,numInCircle=0;
double piEstimate=0.0;

public void init(){
	backCliff= getImage(getCodeBase(),"back.jpg");
	volume = getImage(getCodeBase(),"volume.gif");
	offscreenImage = createImage(this.size().width, this.size().height);
	offscreenGraphics = offscreenImage.getGraphics();
	repaint();
}

public void paint(Graphics g) {
		numInCircle=0;
		offscreenGraphics.drawImage(backCliff,0,0,this);
		offscreenGraphics.drawImage(volume,volPosition,125,this);

	      offscreenGraphics.setColor(Color.black);
//		offscreenGraphics.drawRect(40,42,135,135);
		offscreenGraphics.drawOval(40,42,135,135);

		for (int i=0; i < currspots; i++) {
			offscreenGraphics.fillOval(xspots[i]-2,yspots[i]-2,4,4);
			if (isCircle(xspots[i], yspots[i])) 
				numInCircle++;
		}
 
//area of square =  18225
// r*r	     =  4556.25
//(r*r)/squareA  =  .25
	if (currspots > 0)
		piEstimate=roundDouble((4.0*numInCircle/currspots),5);
	else
		piEstimate=0.0;
 
    		offscreenGraphics.setColor(Color.green);
		offscreenGraphics.drawString(""+volLevel,293,96);
		offscreenGraphics.drawString(""+piEstimate,254,51);
		offscreenGraphics.drawString(""+numInCircle,229,74);
		offscreenGraphics.drawString(""+(currspots-numInCircle),293,74);
		g.drawImage(offscreenImage,0,0,this);

} // Paint

  public double roundDouble(double x, int place) {
	double times=1.0;
	for (int j=0;j<place;j++)
		times=times*10;
	return (Math.round(x*times)/times);
  }

  public boolean isCircle(int x, int y) {
	if (67.5 > Math.sqrt((107.5-x)*(107.5-x) + (109.5-y)*(109.5-y))) 
		return true;
	else
		return false;
  }

  public boolean mouseDown(Event evt, int x, int y) {
	if (x>=40 && x <=175)
		if (y>=42 && y<=177)
			addspot(x,y);

	if (x>=221 && x <=256)		// Fire Pressed
		if (y>=166 && y<=183)
			firePoints();

	if (x>=270 && x <=300)		// Clear Pressed
		if (y>=166 && y<=183)
			clearPoints();

	prevX=x;
	prevY=y;
	System.out.println("x: "+(x)+"y: "+(y));		// Debug position
	return true;
}

public boolean mouseDrag(Event evt, int x, int y) {
	if (x>=202 && x <=318){
		if (y>=121 && y<=145) {
			if (x>=volPosition && x<=(volPosition+25))
				if (prevX < x && volLevel < 500) {
					volPosition=x-10;
					for(int j=0; j<(x-prevX);j++)
						volLevel+=5;
				} 
			if (prevX >= x && volLevel > 0) {
			volPosition=x-10;
				for(int j=0; j<(prevX-x);j++)
					volLevel-=5;
			}
			prevX=x;
			prevY=y;
			if (x>=308)
				volLevel=500;
			if (x<=212)
				volLevel=0;
			if (x == 293)
				volLevel=250;
			repaint();
		}
	}
	return true;
}

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

public void addspot(int x, int y) {
	if (currspots<maxPoints) {
	 	xspots[currspots]=x;
		yspots[currspots]=y;
		currspots++;
		repaint();
	}
}

public void clearPoints() {
	currspots=0;
	repaint();
}

public void firePoints() {
	clearPoints();
	for (int i=0; i < volLevel; i++) {
		addspot((int)(41+Math.random()*135),(int)(43+Math.random()*135));
	}
}

} // End class Prime