I have been trying my best to work out collision detection between Pacman and the walls, however my implementation doesn't seem to work as correctly
Any assistance would be greatly appreciated. thanks in advance
GamePanel.java
package pacman;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import javax.swing.JPanel;
public class GamePanel extends JPanel implements Runnable{
private Thread animator;
private boolean isRunning;
private Map map = new Map();
public GamePanel(){
this.setBackground(Color.BLACK);
this.setDoubleBuffered(true);
addKeyListener(new TAdapter());
setFocusable(true);
}
@Override
public void run() {
isRunning = true;
System.out.println("Is running? "+isRunning);
long startTime, timeDiff, sleepTime;
startTime = System.currentTimeMillis();
while(isRunning){
repaint();
gameUpdate();
timeDiff = System.currentTimeMillis() - startTime;
sleepTime = 5 - timeDiff;
try{
Thread.sleep(sleepTime);
}
catch(InterruptedException ex){
System.exit(0);
}
startTime = System.currentTimeMillis();
}
// gameOver(); not implemented yet, will focus on this when I have some basic animation and the game loop working to satisfaction.
}
@Override
public void addNotify(){
super.addNotify();
startGame();
}
public void startGame(){
if(animator == null || !isRunning){
animator = new Thread(this);
animator.start();
}
} //end of StartGame method
public void gameUpdate(){
map.getPlayer().move();
checkCollision();
} //implementation of ingame updates such as pacman getting killed.
public void checkCollision(){ //this is where I officially set collision up
for(int i = 0; i < map.tiles.length; i++){
for(int j = 0; j < map.tiles.length; j++){
if(map.tiles[i][j] != null){
if(map.getPlayer().getPlayerBox().intersects(map.tiles[i][j].getR())){
map.getPlayer().setColliding(true);
System.out.println("OWW"+map.tiles[i][j].getR().getLocation());
}
}
}
}
}
public void paintComponent(Graphics g){
Graphics2D g2d = (Graphics2D) g;
super.paintComponent(g);
if(isRunning){
drawDot(g2d);
drawPlayer(g2d);
map.drawMap(g2d);
}
Toolkit.getDefaultToolkit().sync();
g.dispose();
}
public void drawDot(Graphics2D g){
g.setColor(Color.GREEN);
for(int x= 0; x < 400; x++){
for(int y = 0; y < 400; y++){
g.drawRect(x * 20, y * 20, 1, 1);
}
}
}
public void drawPlayer(Graphics2D g){
g.drawImage(map.getPlayer().getImage(), map.getPlayer().getX(),map.getPlayer().getY(), this);
}
private class TAdapter extends KeyAdapter{
@Override
public void keyPressed(KeyEvent e) {
map.getPlayer().keyPressed(e);
}
@Override
public void keyReleased(KeyEvent e) {
map.getPlayer().keyReleased(e);
}
}
}
Player.java
package pacman;
import java.awt.Image;
import java.awt.Rectangle;
import java.awt.event.KeyEvent;
import javax.swing.ImageIcon;
public class Player extends Commons{
private int dx, dy;
private int speed = 1;
private static int playerWidth = 52; //these figures seem off, but that is because the image is not designed correctly or the pacman image is not obeying the logic of not going passed the frame size.
private static int playerHeight = 82;
private Rectangle playerBox;
private Image playerImg = new ImageIcon(Player.class.getResource("Pacman.png")).getImage();
private Image playerImgUp = new ImageIcon(Player.class.getResource("PacmanUp.png")).getImage();
private Image playerImgLeft = new ImageIcon(Player.class.getResource("PacmanLeft.png")).getImage();
private Image playerImgDown = new ImageIcon(Player.class.getResource("PacmanDown.png")).getImage();
private boolean isColliding = false;
public Player(){
this.setX(320);
this.setY(280);
playerBox = new Rectangle(this.getX(), this.getY(),40,40);
}
public void setSpeed(int sp){
speed = sp;
}
public Image getImage(){
if(dy == 1){
return playerImgDown;
}
else if(dy == -1){
return playerImgUp;
}
else if(dx == -1){
return playerImgLeft;
}
else
return playerImg;
}//Responsible for displaying pacman image based on direction of pacman's movement.
void move(){
int x = this.getX();
int y = this.getY();
/*
* This is the part where I am trying to implement some degree of logic to stop it from moving
*/
if(isColliding == false){
this.setX(x += dx);
playerBox.setLocation(x, y);
this.setY(y += dy);
}else if(isColliding == true){
this.setColliding(false);
this.setX(this.getX());
this.setY(this.getY());
}
if (this.getX() <= 1) {
this.setX(1);
}
if (this.getX() >= 400 - playerWidth) {
this.setX(400 - playerWidth);
}
if (this.getY() <= 2) {
this.setY(2);
}
if (this.getY() >= 400 - playerHeight ) {
this.setY(400 - playerHeight);
}
}//Most simplist form of collision detection, stops pacman from leaving the JFrame
public void keyPressed(KeyEvent e) {
int key = e.getKeyCode();
if(key == KeyEvent.VK_LEFT ){
dx = -speed;
dy = 0;
}
if(key == KeyEvent.VK_RIGHT){
dx = speed;
dy = 0;
}
if(key == KeyEvent.VK_UP){
dx = 0;
dy = -speed;
}
if(key == KeyEvent.VK_DOWN){
dx = 0;
dy = speed;
}
if(key == KeyEvent.VK_ESCAPE){
System.exit(0);
}
}
public void keyReleased(KeyEvent e) {
int key = e.getKeyCode();
if(key == KeyEvent.VK_LEFT){
dy = 0;
}
if(key == KeyEvent.VK_RIGHT){
dy = 0;
}
if(key == KeyEvent.VK_UP){
dx = 0;
}
if(key == KeyEvent.VK_DOWN){
dx = 0;
}
}//end of key release
public Rectangle getPlayerBox() {
return playerBox;
}
public void setPlayerBox(Rectangle playerBox) {
this.playerBox = playerBox;
}
public boolean isColliding() {
return isColliding;
}
public void setColliding(boolean isColliding) {
this.isColliding = isColliding;
}
}// end of class
It looks like what happens is the player enters a tile which causes collision and isColliding
is set to true.
The next iteration of the game update calls movement code which checks the player's isColliding
boolean. That condition is true and no movement occurs. Next, collision is checked and we haven't moved out of the tile causing the collision so we are stuck in this tile.
I suggest when collision happens to move the player just out of the colliding tile.
We know which direction the player is moving so we can use the inverse direction (multiply dx
and dy
by -1
) to move the player out of the colliding tile.