JFrame gives black screen

Question

This should (or course) show what is done in the paint method, but instead it gives me only a black screen. Sometimes a white screen. Help?
import java.awt.*;
import javax.swing.*;
import java.awt.image.*;
import java.io.*;
import java.math.*;
import java.awt.event.*;
public class ClipAperture extends JFrame{
int imwidth=750; int imheight=750;
BufferedImage copy = new BufferedImage(imwidth, imheight, BufferedImage.TYPE_INT_RGB);
// get Toolkit to get source
Toolkit kit = Toolkit.getDefaultToolkit();
Image source = kit.getImage("Clips.jpg");
Graphics gc = copy.getGraphics();
BufferedImage paste = new BufferedImage(imwidth, imheight, BufferedImage.TYPE_INT_RGB);
Graphics gp = paste.getGraphics();
int ref=1; int refx; int refy;
double r= 88;
int y; int x; int yb; int xb;
int trajectory; double trajrad;
boolean first=true;
ClipAperture() {
super("ClipAperture");
setSize(750, 750);
setBackground(Color.white);
setVisible(true);
public void paint(Graphics g){
g.setColor(Color.white);
g.fillRect(0, 0, 750, 750);
if (first==true){
first=false;
MediaTracker m = new MediaTracker(this);
m.addImage(source, 1);
try { m.waitForAll();
} catch (Exception exec){}
gc.drawImage(source, 0, 0, null);
for(int t=0; t<360; t++) {
double d= Math.toRadians(t);
y=(int)(r*Math.sin(d));
x=(int)(r*Math.cos(d));
trajectory=t-60;
trajrad=Math.toRadians(trajectory);
for(double l=0; l<375; l++) {
yb=y+(int)(l*Math.sin(trajrad));
xb=x+(int)(l*Math.cos(trajrad));
refy=(int)((double)(ref+imwidth/2)/(double)(imwidth));
refx=(int)(Math.IEEEremainder((double)(ref),(double)(imwidth)));
gp.setColor(new Color(copy.getRGB(refx, refy)));
gp.drawLine(xb, yb, xb, yb);
g.drawImage(paste, 0, 0, null);
public static void main(String[] args) {
ClipAperture c = new ClipAperture();
Thanks,
Matt

Answer 1

I fix your code a bit
gc.drawImage(source, 0, 0, null);
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g.drawImage(source, 0, 0, null);
gp.setColor(new Color(copy.getRGB(refx, refy)));
gp.drawLine(xb, yb, xb, yb);
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g.setColor(new Color(copy.getRGB(refx, refy)));
g.drawLine(xb, yb, xb, yb);
g.drawImage(paste, 0, 0, null);
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// g.drawImage(paste, 0, 0, null);