Writing a game of pong.

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rs353

Basically, I have been set an assignment but I am really out of my depth. Pretty much kind of struggling to learn all the languages I am learning atm (C, C++, java, javascript, css, html) and keep up with all of them. Java is my main downfall really, I have been going through tutorials and bits of pieces of the web but really struggling to get my head around it.

I am not expecting someone to use their time to write me a bunch of code, but need a real pointer in the right direction or some kind of decent tutorials that relate to the framework code I am supplied with.

The code is below compiles and shows a basic ball running across a screen (like it would in pong)

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.awt.image.*;
import java.awt.Color;
/*
 * Note If you change S (Speed) collision detection will be
 *      more complex as the ball edge may be within the bat
 *      Ignores concurrency issues (x, y, x_inc, y_inc access)
 */

class Main
{
  public static void main( String args[] ) // 
  {                                        // 
    System.out.println("Application");
    Application app = new Application();
    app.setVisible(true);
    app.run();
  }                                        // 
}

class Application extends JFrame            // So graphical 
{
  private static final int H = 600;         // Height of window 
  private static final int W = 800;         // Width  of window 

  public Application()
  {
    setSize( W, H );                        // Size of application 
    addKeyListener( new Transaction() );    // Called when key press 
    setDefaultCloseOperation(EXIT_ON_CLOSE);
  }


  public void update( Graphics g )          // Called by repaint 
  {                                         // 
    drawPicture( (Graphics2D) g );          // Draw Picture 
  }

  public void paint( Graphics g )           // When 'Window' is first 
  {                                         //  shown or damaged 
    drawPicture( (Graphics2D) g );          // Draw Picture 
  }

  private Dimension     theAD;              // Alternate Dimension 
  private BufferedImage theAI;              // Alternate Image 
  private Graphics2D    theAG;              // Alternate Graphics 

  public void drawPicture( Graphics2D g )   // Double buffer 
  {                                         //  allow re-size 
    Dimension d    = getSize();             // Size of curr. image 

if (  ( theAG == null )  ||
      ( d.width  != theAD.width ) ||
      ( d.height != theAD.height ) )
{                                       // New size 
  theAD = d;
  theAI = (BufferedImage) createImage( d.width, d.height );
  theAG = theAI.createGraphics();
  AffineTransform at = new AffineTransform();
  at.setToIdentity();
  at.scale( ((double)d.width)/W, ((double)d.height)/H );
  theAG.transform(at);
}

drawActualPicture( theAG );             // Draw Actual Picture 
g.drawImage( theAI, 0, 0, this );       //  Display on screen 
  }

  // The ball position and how to increment to next position 

  private int x = W/2, x_inc = 1;
  private int y = H/2, y_inc = 1;

  // Called on key press  

  class Transaction implements KeyListener  // When character typed 
  {
    public void keyPressed(KeyEvent e)      // Obey this method 
    {
     // Key typed includes specials 
     switch ( e.getKeyCode() )              // Character is 
     {
       case KeyEvent.VK_LEFT:               // Left Arrow 
         x_inc = -1;
         break;
       case KeyEvent.VK_RIGHT:              // Right arrow 
         x_inc = 1;
         break;
       case KeyEvent.VK_UP:                 // Up arrow 
         y_inc = -1;
         break;
       case KeyEvent.VK_DOWN:               // Down arrow 
         y_inc = 1;
         break;
      }
      // x,y could send to a server instead of calling  

      repaint();                            // Call update method 
    }

public void keyReleased(KeyEvent e)
{
  // Called on key release including specials 
}

public void keyTyped(KeyEvent e)
{
  // Normal key typed 
  char c = e.getKeyChar();              // Typed 
  repaint();                            // Redraw screen 
}
  }

  private static final int B = 6;           // Border offset 
  private static final int M = 26;          // Menu offset 
  private static final int BALL_SIZE = 10;  // Ball diameter 
  private static final int HALF_BALL_SIZE = BALL_SIZE/2;

  // Code called to draw the current state of the game 

  public void drawActualPicture( Graphics2D g )
  {
    // White background 

g.setPaint( Color.white );
g.fill( new Rectangle2D.Double( 0, 0, W, H ) );

Font font = new Font("Calibri",Font.BOLD,24); 
g.setFont( font ); 

// Blue playing border 

g.setPaint( Color.blue );              // Paint Colour 
g.draw( new Rectangle2D.Double( B, M, W-B*2, H-M-B ) );

// Display state of game 

g.setPaint( Color.blue );
FontMetrics fm = getFontMetrics( font );
String fmt  = "Bouncing Ball x=%4d y = %4d";
String text = String.format( fmt, x, y );
g.drawString( text, W/2-fm.stringWidth(text)/2, M*2 );

// The ball at the current x, y position (width, height) 

g.setPaint( Color.red );
g.fill( new Ellipse2D.Double( x-HALF_BALL_SIZE, y-HALF_BALL_SIZE, 
                              BALL_SIZE,     BALL_SIZE ) );
  }


  // Main program loop 

  public void run()
  {
    final int S = 1;                    // Speed 1 - 5 
    try
    {
      while ( true )
      {
        if ( x >= W-B-HALF_BALL_SIZE ) x_inc = -1*S;
        if ( x <= 0+B+HALF_BALL_SIZE ) x_inc = 1*S;
        if ( y >= H-B-HALF_BALL_SIZE ) y_inc = -1*S;
        if ( y <= 0+M+HALF_BALL_SIZE ) y_inc = 1*S;

    x += x_inc;
    y += y_inc;

    repaint();                      // Now display 

    Thread.sleep( 10 );             // 100 Hz 
  }
} catch ( Exception e ) {};
  }

}

The minimum objectives I would like to achieve are
- Insert 2 paddles that can be moved using W/S and UP/DOWN which the ball collides with
- Insert a score for both players at top of screen rather than current text
- Change the background image to something over than a basic colour.

Thankyou for any replies.

In the meantime I will work on my C program in arduino to take random numbers and display them in binary

cyberbemon

- Insert 2 paddles that can be moved using W/S and UP/DOWN which the ball collides with

Load the images of the paddles , make 2 int variables assign a value of ,lets say +5 and -5 to each of them.. when the player presses the Up arrow/W key change the current position of the paddle by +5 and when they press the down arrow/S change it by -5 and call the repaint() after that

- Insert a score for both players at top of screen rather than current text

for scores have 2 integers lets call them Score_Player1 and Score_player2
and in your PaintComponent(Graphics g)

 //Draw scores

            gc.drawString("Player 1: "+Score_Player1, 25, 10);

            gc.drawString("Player 2: "+Score_Player2, 150, 10);

- Change the background image to something over than a basic colour.
you can use either toolkit or the Image class
here is an example of using them both

 Image bgimg = Toolkit.getDefaultToolkit().createImage("background.jpg");

and using the Image class

Image bgimg = ImageIO.read(new File("background.jpg");

now since you are using swing, we need to override the paintComponent method of the JComponent, and draw the Image
and here is how we do that

public void paintComponent(Graphics g)
{
&#12288;&#12288;&#12288;&#12288;// Draw the previously loaded image to Component.
&#12288;&#12288;&#12288;&#12288;g.drawImage(bgimg, 0, 0, null);

&#12288;&#12288;&#12288;&#12288;// Draw sprites, and other things.
&#12288;&#12288;&#12288;&#12288;// ....
}

rs353

Cheers for the reply, I had found out about the paddles and getting them moving about, but the image and scores advice was quality thanks