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

/*<applet code="Es2_Im.class" width = 450 height = 300>
</applet>*/

public class Es2_Im extends Applet{

int w,h;
Image img;
Graphics mg;

public void init(){

setBackground(new Color(128,0,255));
w = getSize().width;
h = getSize().height;
img = createImage(new MemoryImageSource(w,h,fillPix(w,h),0,w));
	}

double C(double x, double y){
	return Math.cos((x*x + y*y)/200);//provare anche 600,6000
	}

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

public int[] fillPix(int w, int h){
	
int X = (w + (int)(0.807 * h))/2;
int Y = h/2;
int[] pix = new int[w*h];

for(int x = 0; x < w; x++){
	for(int y = 0; y<h ; y++){
		int r = (int)((C(x-X, y-Y)+1)*127);
		pix[x+y*w] = (255 << 24|128 << 16|r << 8|128);
		}
	}
return pix;
  }
}