Java Game Programming Basics

// The Board is a panel, where the game takes place.

package com.zetcode.main;

import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.RenderingHints;
import java.awt.geom.AffineTransform;
import java.awt.geom.Ellipse2D;
import javax.swing.*;

@SuppressWarnings("serial")
public class Board extends JPanel
{
	public void paint(Graphics g)
	{
		super.paint(g);

		// Provides a sophisticated control over painting
		Graphics2D g2 = (Graphics2D) g;

		// The rendering hints are used to make the drawing smooth
		RenderingHints rh = new RenderingHints(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);

		rh.put(RenderingHints.KEY_RENDERING, RenderingHints.VALUE_RENDER_QUALITY);

		g2.setRenderingHints(rh);

		// We get the height and the width of the window
	    Dimension size = getSize();
	    double w = size.getWidth();
	    double h = size.getHeight();

	    // Here we create the ellipse
	    Ellipse2D e = new Ellipse2D.Double(0, 0, 80, 130);
	    g2.setStroke(new BasicStroke(1));
	    g2.setColor(Color.gray);

	    // Here the ellipse is rotated 72 times to create a "donut"
	    for (double deg = 0; deg < 360; deg += 5) {
	          AffineTransform at = AffineTransform.getTranslateInstance(w / 2, h / 2);
	          at.rotate(Math.toRadians(deg));
	          g2.draw(at.createTransformedShape(e));
	        }
	}
}
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package com.zetcode.main;

import javax.swing.*;

public class Zetcode extends JFrame
{
	private static final int WIDTH = 360;
	private static final int HEIGHT = 310;

	public Zetcode()
	{
		add(new Board());
		setVisible(true);
		setTitle("Donut");
		setSize(WIDTH, HEIGHT);
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		setLocationRelativeTo(null);
		setResizable(false);
	}

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