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A simple Tetris clone written in Java
import java.awt.Color;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.ArrayList;
import java.util.Collections;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class Tetris extends JPanel {
private static final long serialVersionUID = -8715353373678321308L;
private final Point[][][] Tetraminos = {
// I-Piece
{
{ new Point(0, 1), new Point(1, 1), new Point(2, 1), new Point(3, 1) },
{ new Point(1, 0), new Point(1, 1), new Point(1, 2), new Point(1, 3) },
{ new Point(0, 1), new Point(1, 1), new Point(2, 1), new Point(3, 1) },
{ new Point(1, 0), new Point(1, 1), new Point(1, 2), new Point(1, 3) }
},
// J-Piece
{
{ new Point(0, 1), new Point(1, 1), new Point(2, 1), new Point(2, 0) },
{ new Point(1, 0), new Point(1, 1), new Point(1, 2), new Point(2, 2) },
{ new Point(0, 1), new Point(1, 1), new Point(2, 1), new Point(0, 2) },
{ new Point(1, 0), new Point(1, 1), new Point(1, 2), new Point(0, 0) }
},
// L-Piece
{
{ new Point(0, 1), new Point(1, 1), new Point(2, 1), new Point(2, 2) },
{ new Point(1, 0), new Point(1, 1), new Point(1, 2), new Point(0, 2) },
{ new Point(0, 1), new Point(1, 1), new Point(2, 1), new Point(0, 0) },
{ new Point(1, 0), new Point(1, 1), new Point(1, 2), new Point(2, 0) }
},
// O-Piece
{
{ new Point(0, 0), new Point(0, 1), new Point(1, 0), new Point(1, 1) },
{ new Point(0, 0), new Point(0, 1), new Point(1, 0), new Point(1, 1) },
{ new Point(0, 0), new Point(0, 1), new Point(1, 0), new Point(1, 1) },
{ new Point(0, 0), new Point(0, 1), new Point(1, 0), new Point(1, 1) }
},
// S-Piece
{
{ new Point(1, 0), new Point(2, 0), new Point(0, 1), new Point(1, 1) },
{ new Point(0, 0), new Point(0, 1), new Point(1, 1), new Point(1, 2) },
{ new Point(1, 0), new Point(2, 0), new Point(0, 1), new Point(1, 1) },
{ new Point(0, 0), new Point(0, 1), new Point(1, 1), new Point(1, 2) }
},
// T-Piece
{
{ new Point(1, 0), new Point(0, 1), new Point(1, 1), new Point(2, 1) },
{ new Point(1, 0), new Point(0, 1), new Point(1, 1), new Point(1, 2) },
{ new Point(0, 1), new Point(1, 1), new Point(2, 1), new Point(1, 2) },
{ new Point(1, 0), new Point(1, 1), new Point(2, 1), new Point(1, 2) }
},
// Z-Piece
{
{ new Point(0, 0), new Point(1, 0), new Point(1, 1), new Point(2, 1) },
{ new Point(1, 0), new Point(0, 1), new Point(1, 1), new Point(0, 2) },
{ new Point(0, 0), new Point(1, 0), new Point(1, 1), new Point(2, 1) },
{ new Point(1, 0), new Point(0, 1), new Point(1, 1), new Point(0, 2) }
}
};
private final Color[] tetraminoColors = {
Color.cyan, Color.blue, Color.orange, Color.yellow, Color.green, Color.pink, Color.red
};
private Point pieceOrigin;
private int currentPiece;
private int rotation;
private ArrayList<Integer> nextPieces = new ArrayList<Integer>();
private long score;
private Color[][] well;
// Creates a border around the well and initializes the dropping piece
private void init() {
well = new Color[12][24];
for (int i = 0; i < 12; i++) {
for (int j = 0; j < 23; j++) {
if (i == 0 || i == 11 || j == 22) {
well[i][j] = Color.GRAY;
} else {
well[i][j] = Color.BLACK;
}
}
}
newPiece();
}
// Put a new, random piece into the dropping position
public void newPiece() {
pieceOrigin = new Point(5, 2);
rotation = 0;
if (nextPieces.isEmpty()) {
Collections.addAll(nextPieces, 0, 1, 2, 3, 4, 5, 6);
Collections.shuffle(nextPieces);
}
currentPiece = nextPieces.get(0);
nextPieces.remove(0);
}
// Collision test for the dropping piece
private boolean collidesAt(int x, int y, int rotation) {
for (Point p : Tetraminos[currentPiece][rotation]) {
if (well[p.x + x][p.y + y] != Color.BLACK) {
return true;
}
}
return false;
}
// Rotate the piece clockwise or counterclockwise
public void rotate(int i) {
int newRotation = (rotation + i) % 4;
if (newRotation < 0) {
newRotation = 3;
}
if (!collidesAt(pieceOrigin.x, pieceOrigin.y, newRotation)) {
rotation = newRotation;
}
repaint();
}
// Move the piece left or right
public void move(int i) {
if (!collidesAt(pieceOrigin.x + i, pieceOrigin.y, rotation)) {
pieceOrigin.x += i;
}
repaint();
}
// Drops the piece one line or fixes it to the well if it can't drop
public void dropDown() {
if (!collidesAt(pieceOrigin.x, pieceOrigin.y + 1, rotation)) {
pieceOrigin.y += 1;
} else {
fixToWell();
}
repaint();
}
// Make the dropping piece part of the well, so it is available for
// collision detection.
public void fixToWell() {
for (Point p : Tetraminos[currentPiece][rotation]) {
well[pieceOrigin.x + p.x][pieceOrigin.y + p.y] = tetraminoColors[currentPiece];
}
clearRows();
newPiece();
}
public void deleteRow(int row) {
for (int j = row-1; j > 0; j--) {
for (int i = 1; i < 11; i++) {
well[i][j+1] = well[i][j];
}
}
}
// Clear completed rows from the field and award score according to
// the number of simultaneously cleared rows.
public void clearRows() {
boolean gap;
int numClears = 0;
for (int j = 21; j > 0; j--) {
gap = false;
for (int i = 1; i < 11; i++) {
if (well[i][j] == Color.BLACK) {
gap = true;
break;
}
}
if (!gap) {
deleteRow(j);
j += 1;
numClears += 1;
}
}
switch (numClears) {
case 1:
score += 100;
break;
case 2:
score += 300;
break;
case 3:
score += 500;
break;
case 4:
score += 800;
break;
}
}
// Draw the falling piece
private void drawPiece(Graphics g) {
g.setColor(tetraminoColors[currentPiece]);
for (Point p : Tetraminos[currentPiece][rotation]) {
g.fillRect((p.x + pieceOrigin.x) * 26,
(p.y + pieceOrigin.y) * 26,
25, 25);
}
}
@Override
public void paintComponent(Graphics g)
{
// Paint the well
g.fillRect(0, 0, 26*12, 26*23);
for (int i = 0; i < 12; i++) {
for (int j = 0; j < 23; j++) {
g.setColor(well[i][j]);
g.fillRect(26*i, 26*j, 25, 25);
}
}
// Display the score
g.setColor(Color.WHITE);
g.drawString("" + score, 19*12, 25);
// Draw the currently falling piece
drawPiece(g);
}
public static void main(String[] args) {
JFrame f = new JFrame("Tetris");
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setSize(12*26+10, 26*23+25);
f.setVisible(true);
final Tetris game = new Tetris();
game.init();
f.add(game);
// Keyboard controls
f.addKeyListener(new KeyListener() {
public void keyTyped(KeyEvent e) {
}
public void keyPressed(KeyEvent e) {
switch (e.getKeyCode()) {
case KeyEvent.VK_UP:
game.rotate(-1);
break;
case KeyEvent.VK_DOWN:
game.rotate(+1);
break;
case KeyEvent.VK_LEFT:
game.move(-1);
break;
case KeyEvent.VK_RIGHT:
game.move(+1);
break;
case KeyEvent.VK_SPACE:
game.dropDown();
game.score += 1;
break;
}
}
public void keyReleased(KeyEvent e) {
}
});
// Make the falling piece drop every second
new Thread() {
@Override public void run() {
while (true) {
try {
Thread.sleep(1000);
game.dropDown();
} catch ( InterruptedException e ) {}
}
}
}.start();
}
}
@Jasmin95

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Jasmin95 commented Aug 26, 2016

no game over?

@k-abdelmesih

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k-abdelmesih commented Feb 24, 2017

Hello DataWraith,

As a Software Engineering student at McMaster University, I had chosen to work with your project (Tetris) for one of my assignments.
The main task is to document the source code according to given guidelines. I was hoping that you would be able to revise my proposed comments and documentation and potentially merge those changes with your current project. I am sending you this as a comment as it is not possible to create pull requests on GitHub Gist, surprisingly. The changes I propose can be found on my public fork under this project.

Thank you for your time, and hope that you accept to merge.

Regards,
Kareem Abdel Mesih

@magon15

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magon15 commented Jul 16, 2017

Good day. The fork that I created adds additional functionality to your Tetris game, and with it you'll be able to see the theoretical position of the moving block. You'll probably learn something from the code I've written, for I'm also making my own Tetris game.

I could see improvements that could be added like adding a 'Game Over' feature, but your coding cleanliness is exceptional, and I even tried to implement the 'well array' idea to my own app.

Thanks, and I would love it if you could merge this.

@urielsomb

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urielsomb commented May 15, 2018

Hi, I can't seem to run this on bluej

@klenium

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klenium commented Jul 14, 2018

The tetr-a-mino is a typo. It's called tetr-o-mino, though we use the word tetra for 4-something.

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