# Java awt draw elements around a circle

I’m currently writing a little game and I came over a problem. I need to draw 64 small circles at the border of a big circle. So I want something like this: I’ve already tried many things, but they didn’t worked. How can this be done in java, using the java.awt.Component#paint() method and the java.awt.Graphics class?

Thanks.

So, your basic problem comes down to “find a point on a circle based on a given angle”

A quick google will find resources like Find the coordinates of a point on a circle, now, to be frank, I’m an idiot, so I’d narrow my search to include Java, which would give us something like How to calculate the coordinates of points in a circle using Java? – sweet.

So the basic calculation might look something like

```double xPosy = Math.cos(rads) * radius);
```

Now, this solves the core aspect of your problem. The rest comes down to simply painting the results. See Performing Custom Painting and Painting in AWT and Swing as a starting point and 2D Graphics for a more detailed look into the API.

Now, taking all of the above, you might end up with a solution looking something like… ```import java.awt.Color;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class Test {

public static void main(String[] args) {
new Test();
}

public Test() {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
JFrame frame = new JFrame();
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}

public class TestPane extends JPanel {

public TestPane() {
}

@Override
public Dimension getPreferredSize() {
return new Dimension(200, 200);
}

@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d = (Graphics2D) g.create();
int midX = getWidth() / 2;
int midY = getHeight() / 2;
Dimension size = new Dimension(4, 4);
g2d.setColor(Color.BLACK);
for (int index = 0; index < 64; index++) {
double angle = (360d / 64d) * index;
Point2D poc = getPointOnCircle(angle, 100 - 4);
Rectangle2D box = new Rectangle2D.Double(midX + poc.getX() - 2, midY + poc.getY() - 2, size.width, size.height);
g2d.draw(box);
}
g2d.dispose();
}

protected Point2D getPointOnCircle(double degress, double radius) {
If I was approaching this problem I might be tempted, to create a custom shape or, apply a 45 degree transformation to the `box` and the translate it’s position to render it or just rotate the whole result by 45 degrees, but this brings a whole bag of other issues depending on what you want to do with it