Hi everyone. I have to do a simple Sokoban game, but I am new in Java and I really don't know how to begin. If you can help me with some advices or tutorials I'll be very thankful.
chira.laura.9 0 Newbie Poster
tux4life 2,072 Postaholic
Where do you have problems with in specific?
I'd suggest you to perform a Google search on 'Sokoban', look at existing implementations, play a couple of them and see how it works.
Familiarize yourself with the rules of the game. Start coding, and when you encounter problems come back and ask for help.
chira.laura.9 0 Newbie Poster
Ok. Thank you:)
bguild 163 Posting Whiz
Of course what you really want is a 2D array to store the current state of the game, an x and y variable to store the current location of your little warehouse manager guy, a list of (x,y) target points for the boxes, a javax.swing.JPanel to draw everything, and a java.awt.event.KeyListener on that JPanel to allow the keyboard to control the warehouse worker. Once you have that, you are practically done except for the frills.
chira.laura.9 0 Newbie Poster
Here is a code for the Sobokan Board. I took it from http://zetcode.com/tutorials/javagamestutorial/sokoban/, and I made some changes.
I get an error:Exception in thread "main" java.lang.NullPointerException
package sokoban;
import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.util.ArrayList;
import javax.swing.JPanel;
@SuppressWarnings("serial")
public class Board extends JPanel
{
private final int DISTANCE_BORDER_GAMEGRAPHICS = 30;
private final int SPACE = 20;
private final int LEFT_COLLISION = 1;
private final int RIGHT_COLLISION = 2;
private final int UP_COLLISION = 3;
private final int DOWN_COLLISION = 4;
private ArrayList<Wall> Walls;
private ArrayList<Objective> Objectives;
private ArrayList<Box> Boxes;
private Player soko;
private int width = 0;
private int height = 0;
private boolean completed = false;
private String level =
" ######\n"
+ " ##** #\n"
+ " ##$ #\n"
+ " #### @ $##\n"
+ " #########\n";
public Board() {
addKeyListener(new SokoAdapter());
setFocusable(true);
initiateGame();
}
public int getBoardWidth() {
return this.width;
}
public int getBoardHeight() {
return this.height;
}
public final void initiateGame() {
int x = DISTANCE_BORDER_GAMEGRAPHICS;
int y = DISTANCE_BORDER_GAMEGRAPHICS;
Wall wall;
Box box;
Objective objective;
for (int i = 0; i < level.length(); i++) {
char item = level.charAt(i);
if (item == '\n') {
y += SPACE;
if (this.width < x) {
this.width = x;
}
x = DISTANCE_BORDER_GAMEGRAPHICS;
} else if (item == '#') {
wall = new Wall(x, y);
Walls.add(wall);
x += SPACE;
} else if (item == '$') {
box = new Box(x, y);
Boxes.add(box);
x += SPACE;
} else if (item == '*') {
objective = new Objective(x, y);
Objectives.add(objective);
x += SPACE;
} else if (item == '@') {
soko = new Player(x, y);
x += SPACE;
} else if (item == ' ') {
x += SPACE;
}
height = y;
}
}
public void buildGame(Graphics g) {
g.setColor(new Color(250, 240, 170));
g.fillRect(0, 0, this.getWidth(), this.getHeight());
ArrayList world = new ArrayList();
world.addAll(Walls);
world.addAll(Objectives);
world.addAll(Boxes);
world.add(soko);
for (int i = 0; i < world.size(); i++) {
Actor item = (Actor) world.get(i);
if ((item instanceof Player)
|| (item instanceof Box)) {
g.drawImage(item.getImage(), item.x() + 2, item.y() + 2, this);
} else {
g.drawImage(item.getImage(), item.x(), item.y(), this);
}
if (completed) {
g.setColor(new Color(0, 0, 0));
g.drawString("Completed", 25, 20);
}
}
}
@Override
public void paint(Graphics g) {
super.paint(g);
buildGame(g);
}
class SokoAdapter extends KeyAdapter {
@Override
public void keyPressed(KeyEvent e) {
if (completed) {
return;
}
int key = e.getKeyCode();
if (key == KeyEvent.VK_LEFT) {
if (checkWallCollision(soko, LEFT_COLLISION)) {
return;
}
if (checkBoxCollision(LEFT_COLLISION)) {
return;
}
soko.move(-SPACE, 0);
} else if (key == KeyEvent.VK_RIGHT) {
if (checkWallCollision(soko,
RIGHT_COLLISION)) {
return;
}
if (checkBoxCollision(RIGHT_COLLISION)) {
return;
}
soko.move(SPACE, 0);
} else if (key == KeyEvent.VK_UP) {
if (checkWallCollision(soko,
UP_COLLISION)) {
return;
}
if (checkBoxCollision(UP_COLLISION)) {
return;
}
soko.move(0, -SPACE);
} else if (key == KeyEvent.VK_DOWN) {
if (checkWallCollision(soko,
DOWN_COLLISION)) {
return;
}
if (checkBoxCollision(DOWN_COLLISION)) {
return;
}
soko.move(0, SPACE);
} else if (key == KeyEvent.VK_R) {
restartLevel();
}
repaint();
}
}
private boolean checkWallCollision(Actor actor, int type) {
if (type == LEFT_COLLISION) {
for (int i = 0; i < Walls.size(); i++) {
Wall wall = (Wall) Walls.get(i);
if (actor.isLeftCollision(wall)) {
return true;
}
}
return false;
} else if (type == RIGHT_COLLISION) {
for (int i = 0; i < Walls.size(); i++) {
Wall wall = (Wall) Walls.get(i);
if (actor.isRightCollision(wall)) {
return true;
}
}
return false;
} else if (type == UP_COLLISION) {
for (int i = 0; i < Walls.size(); i++) {
Wall wall = (Wall) Walls.get(i);
if (actor.isTopCollision(wall)) {
return true;
}
}
return false;
} else if (type == DOWN_COLLISION) {
for (int i = 0; i < Walls.size(); i++) {
Wall wall = (Wall) Walls.get(i);
if (actor.isBottomCollision(wall)) {
return true;
}
}
return false;
}
return false;
}
private boolean checkBoxCollision(int type) {
if (type == LEFT_COLLISION) {
for (int i = 0; i < Boxes.size(); i++) {
Box box = (Box) Boxes.get(i);
if (soko.isLeftCollision(box)) {
for (int j=0; j < Boxes.size(); j++) {
Box item = (Box) Boxes.get(j);
if (!box.equals(item)) {
if (box.isLeftCollision(item)) {
return true;
}
}
if (checkWallCollision(box,
LEFT_COLLISION)) {
return true;
}
}
box.move(-SPACE, 0);
isCompleted();
}
}
return false;
} else if (type == RIGHT_COLLISION) {
for (int i = 0; i < Boxes.size(); i++) {
Box box = (Box) Boxes.get(i);
if (soko.isRightCollision(box)) {
for (int j=0; j < Boxes.size(); j++) {
Box item = (Box) Boxes.get(j);
if (!box.equals(item)) {
if (box.isRightCollision(item)) {
return true;
}
}
if (checkWallCollision(box,
RIGHT_COLLISION)) {
return true;
}
}
box.move(SPACE, 0);
isCompleted();
}
}
return false;
} else if (type == UP_COLLISION) {
for (int i = 0; i < Boxes.size(); i++) {
Box box = (Box) Boxes.get(i);
if (soko.isTopCollision(box)) {
for (int j = 0; j < Boxes.size(); j++) {
Box item = (Box) Boxes.get(j);
if (!box.equals(item)) {
if (box.isTopCollision(item)) {
return true;
}
}
if (checkWallCollision(box,
UP_COLLISION)) {
return true;
}
}
box.move(0, -SPACE);
isCompleted();
}
}
return false;
} else if (type == DOWN_COLLISION) {
for (int i = 0; i < Boxes.size(); i++) {
Box box = (Box) Boxes.get(i);
if (soko.isBottomCollision(box)) {
for (int j = 0; j < Boxes.size(); j++) {
Box item = (Box) Boxes.get(j);
if (!box.equals(item)) {
if (box.isBottomCollision(item)) {
return true;
}
}
if (checkWallCollision(box,
DOWN_COLLISION)) {
return true;
}
}
box.move(0, SPACE);
isCompleted();
}
}
}
return false;
}
public void isCompleted() {
int num = Boxes.size();
int compl = 0;
for (int i = 0; i < num; i++) {
Box box = (Box) Boxes.get(i);
for (int j = 0; j < num; j++) {
Objective Objective = (Objective) Objectives.get(j);
if (box.x() == Objective.x()
&& box.y() == Objective.y()) {
compl += 1;
}
}
}
if (compl == num) {
completed = true;
repaint();
}
}
public void restartLevel() {
Objectives.clear();
Boxes.clear();
Walls.clear();
initiateGame();
if (completed) {
completed = false;
}
}
}
bguild 163 Posting Whiz
I suggest that you make one yourself from scratch. It's really a nice simple game that can be made from scratch without excessive effort. The way it is done above is certainly using excessive effort. Instead of using a 2D array to represent the board, it is using sprites and collision detection for no apparent reason. I would abandon that whole implementation of Sokoban and make something simpler if I were you.
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