I am extending a Canvas and adding it to a JFrame. I understand that AWT and Swing should not be mixed and that drawing on JPanel is preferred but i’m trying to follow a game engine tutorial and i’d like to stick to it since I got it working so far. The Canvas has minimumSize, maximumSize, and prefferedSize set to the dimensions of 550, 400. When I do a draw call graphics.draw(0,0,550,400) it doesn’t fill the entire screen as it should. I changed the draw call to graphics.draw(0,0,560,410) essentially adding 10px to it and it filled the entire screen. Whats wrong?
BTW: graphics.draw(10,10,550,400 draws the rectangle starting at the corner exactly so I don’t think the JFrame is the issue.
The main call inside Launcher class
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
game.setMinimumSize(DIMENSIONS);
game.setMaximumSize(DIMENSIONS);
game.setPreferredSize(DIMENSIONS);
game.frame = new JFrame(NAME);
game.frame.setLayout(new BorderLayout());
game.frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
game.frame.add(game, BorderLayout.CENTER);
game.frame.pack();
game.frame.setResizable(false);
game.frame.setLocationRelativeTo(null);
game.frame.setVisible(true);
Logger.log(TAG, "Game starting");
game.start();
}
});
}
The draw call, Launcher.HEIGHT and WIDTH are 550,400
public void draw(float deltaTime, Graphics2D graphics) {
graphics.setColor(Color.BLACK);
graphics.fillRect(0, 0, 550, 400);
graphics.setColor(Color.DARK_GRAY);
graphics.fillRect(0, 0, 150, 40);
graphics.fillRect(0, Launcher.HEIGHT - 100, Launcher.WIDTH, 100);
graphics.setColor(Color.LIGHT_GRAY);
graphics.fillRect(125, Launcher.HEIGHT - 100, 100, 350);
}
The extended Canvas class
public abstract class Game extends Canvas implements Runnable {
private static final String TAG = "Game";
public JFrame frame;
public JPanel panel;
public boolean isApplet = false;
private boolean gameRunning = false;
BufferStrategy bufferStrategy;
private Screen screen;
private Thread renderThread;
public synchronized void start() {
// Canvas
setBounds(0, 0, 550, 400);
setIgnoreRepaint(true);
createBufferStrategy(2);
bufferStrategy = getBufferStrategy();
// Screen, Handlers, ETC
screen = getStartScreen();
// Threads
renderThread = new Thread(this, Launcher.NAME + "_main");
renderThread.start();
gameRunning = true;
}
@Override
public void run() {
long startTime = System.nanoTime();
while (gameRunning) {
float deltaTime = (System.nanoTime() - startTime) / 1000000000.0f;
startTime = System.nanoTime();
screen.update(deltaTime);
Graphics2D graphics = (Graphics2D) bufferStrategy.getDrawGraphics();
screen.draw(deltaTime, graphics);
graphics.dispose();
bufferStrategy.show();
// FPS Counter
// FPS Capper
}
}
}
Reqested SSCCE
import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics2D;
import java.awt.image.BufferStrategy;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
@SuppressWarnings("serial")
public class Game extends Canvas implements Runnable {
public static final int WIDTH = 550;
public static final int HEIGHT = 400;
public static final Dimension DIMENSIONS = new Dimension(WIDTH, HEIGHT);
public static final String NAME = "SSCCE";
public boolean gameRunning = false;
public JFrame frame;
public BufferStrategy bufferStrategy;
public static void main (String[] args) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
Game game = new Game();
game.setMinimumSize(DIMENSIONS);
game.setMaximumSize(DIMENSIONS);
game.setPreferredSize(DIMENSIONS);
game.frame = new JFrame(NAME);
game.frame.setLayout(new BorderLayout());
game.frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
game.frame.add(game, BorderLayout.CENTER);
game.frame.pack();
game.frame.setResizable(false);
game.frame.setLocationRelativeTo(null);
game.frame.setVisible(true);
System.out.println("Game started");
game.start();
}
});
}
public synchronized void start() {
setSize(550, 400);
setBounds(0, 0, 550, 400);
setIgnoreRepaint(true);
createBufferStrategy(2);
bufferStrategy = getBufferStrategy();
// Threads
Thread renderThread = new Thread(this, NAME + "_main");
renderThread.start();
gameRunning = true;
}
@Override
public void run() {
while (gameRunning) {
Graphics2D graphics = (Graphics2D) bufferStrategy.getDrawGraphics();
graphics.setColor(Color.BLACK);
graphics.fillRect(0, 0, WIDTH, HEIGHT);
graphics.dispose();
bufferStrategy.show();
}
}
}
As for the Java 2D game tutorial I am following it is a web series. Nevertheless, the link is the following click here. I modified the code quite a lot.
Modified for MadProgrammer
import java.awt.BorderLayout;
import java.awt.Canvas;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics2D;
import java.awt.image.BufferStrategy;
import javax.swing.JFrame;
import javax.swing.SwingUtilities;
@SuppressWarnings("serial")
public class Game extends Canvas implements Runnable {
public static final int WIDTH = 550;
public static final int HEIGHT = 400;
public static final Dimension DIMENSIONS = new Dimension(WIDTH, HEIGHT);
public static final String NAME = "SSCCE";
public boolean gameRunning = false;
public JFrame frame;
public BufferStrategy bufferStrategy;
public static void main (String[] args) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
Game game = new Game();
game.setMinimumSize(DIMENSIONS);
game.setMaximumSize(DIMENSIONS);
game.setPreferredSize(DIMENSIONS);
game.frame = new JFrame(NAME);
game.frame.setLayout(new BorderLayout());
game.frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
game.frame.add(game, BorderLayout.CENTER);
game.frame.pack();
game.frame.setResizable(false);
game.frame.setLocationRelativeTo(null);
game.frame.setVisible(true);
System.out.println("Game started");
game.start();
}
});
}
public synchronized void start() {
setSize(550, 400);
setBounds(0, 0, 550, 400);
setIgnoreRepaint(true);
createBufferStrategy(2);
bufferStrategy = getBufferStrategy();
// Threads
Thread renderThread = new Thread(this, NAME + "_main");
renderThread.start();
gameRunning = true;
}
@Override
public void run() {
while (gameRunning) {
Graphics2D graphics = (Graphics2D) bufferStrategy.getDrawGraphics();
graphics.setColor(Color.RED);
// Using getWidth()
graphics.fillRect(0, 0, getWidth(), getHeight());
graphics.setColor(Color.GREEN);
// Using WIDTH which was used to set the size of the canvas
graphics.fillRect(5, 5, WIDTH, HEIGHT);
graphics.dispose();
bufferStrategy.show();
try {
Thread.sleep(60);
} catch (InterruptedException ex) {
}
}
}
}
The example you’ve provide works fine. I modified it a little to demonstrate the use of
getWidth/height