In Tetris, players complete lines by moving differently shaped pieces (tetrominoes), which descend onto the playing field. The completed lines disappear and grant the player points, and the player can proceed to fill the vacated spaces. The game ends when the uncleared lines reach the top of the playing field. The longer the player can delay this outcome, the higher their score will be. In multiplayer games, players must last longer than their opponents; in certain versions, players can inflict penalties on opponents by completing a significant number of lines. Some versions add variations on the rules, such as three-dimensional displays or a system for reserving pieces.

html cod

<!DOCTYPE html>
	<html>
	<head>
	<title>Basic Tetris HTML Game</title>
	<meta charset="UTF-8">
	<style>
	html, body {
	height: 100%;
	margin: 0;
	}

	body {
	background: black;
	display: flex;
	align-items: center;
	justify-content: center;
	}

	canvas {
	border: 1px solid white;
	}
	</style>
	</head>
	<body>
	<canvas width="320" height="640" id="game"></canvas>
	<script>
	// https://tetris.fandom.com/wiki/Tetris_Guideline

	// get a random integer between the range of [min,max]
	// @see https://stackoverflow.com/a/1527820/2124254
	function getRandomInt(min, max) {
	min = Math.ceil(min);
	max = Math.floor(max);

	return Math.floor(Math.random() * (max - min + 1)) + min;
	}

	// generate a new tetromino sequence
	// @see https://tetris.fandom.com/wiki/Random_Generator
	function generateSequence() {
	const sequence = ['I', 'J', 'L', 'O', 'S', 'T', 'Z'];

	while (sequence.length) {
	const rand = getRandomInt(0, sequence.length - 1);
	const name = sequence.splice(rand, 1)[0];
	tetrominoSequence.push(name);
	}
	}

	// get the next tetromino in the sequence
	function getNextTetromino() {
	if (tetrominoSequence.length === 0) {
	generateSequence();
	}

	const name = tetrominoSequence.pop();
	const matrix = tetrominos[name];

	// I and O start centered, all others start in left-middle
	const col = playfield[0].length / 2 - Math.ceil(matrix[0].length / 2);

	// I starts on row 21 (-1), all others start on row 22 (-2)
	const row = name === 'I' ? -1 : -2;

	return {
	name: name, // name of the piece (L, O, etc.)
	matrix: matrix, // the current rotation matrix
	row: row, // current row (starts offscreen)
	col: col // current col
	};
	}

	// rotate an NxN matrix 90deg
	// @see https://codereview.stackexchange.com/a/186834
	function rotate(matrix) {
	const N = matrix.length - 1;
	const result = matrix.map((row, i) =>
	row.map((val, j) => matrix[N - j][i])
	);

	return result;
	}

	// check to see if the new matrix/row/col is valid
	function isValidMove(matrix, cellRow, cellCol) {
	for (let row = 0; row < matrix.length; row++) {
	for (let col = 0; col < matrix[row].length; col++) {
	if (matrix[row][col] && (
	// outside the game bounds
	cellCol + col < 0 \|\|
	cellCol + col >= playfield[0].length \|\|
	cellRow + row >= playfield.length \|\|
	// collides with another piece
	playfield[cellRow + row][cellCol + col])
	) {
	return false;
	}
	}
	}

	return true;
	}

	// place the tetromino on the playfield
	function placeTetromino() {
	for (let row = 0; row < tetromino.matrix.length; row++) {
	for (let col = 0; col < tetromino.matrix[row].length; col++) {
	if (tetromino.matrix[row][col]) {

	// game over if piece has any part offscreen
	if (tetromino.row + row < 0) {
	return showGameOver();
	}

	playfield[tetromino.row + row][tetromino.col + col] = tetromino.name;
	}
	}
	}

	// check for line clears starting from the bottom and working our way up
	for (let row = playfield.length - 1; row >= 0; ) {
	if (playfield[row].every(cell => !!cell)) {

	// drop every row above this one
	for (let r = row; r >= 0; r--) {
	for (let c = 0; c < playfield[r].length; c++) {
	playfield[r][c] = playfield[r-1][c];
	}
	}
	}
	else {
	row--;
	}
	}

	tetromino = getNextTetromino();
	}

	// show the game over screen
	function showGameOver() {
	cancelAnimationFrame(rAF);
	gameOver = true;

	context.fillStyle = 'black';
	context.globalAlpha = 0.75;
	context.fillRect(0, canvas.height / 2 - 30, canvas.width, 60);

	context.globalAlpha = 1;
	context.fillStyle = 'white';
	context.font = '36px monospace';
	context.textAlign = 'center';
	context.textBaseline = 'middle';
	context.fillText('GAME OVER!', canvas.width / 2, canvas.height / 2);
	}

	const canvas = document.getElementById('game');
	const context = canvas.getContext('2d');
	const grid = 32;
	const tetrominoSequence = [];

	// keep track of what is in every cell of the game using a 2d array
	// tetris playfield is 10x20, with a few rows offscreen
	const playfield = [];

	// populate the empty state
	for (let row = -2; row < 20; row++) {
	playfield[row] = [];

	for (let col = 0; col < 10; col++) {
	playfield[row][col] = 0;
	}
	}

	// how to draw each tetromino
	// @see https://tetris.fandom.com/wiki/SRS
	const tetrominos = {
	'I': [
	[0,0,0,0],
	[1,1,1,1],
	[0,0,0,0],
	[0,0,0,0]
	],
	'J': [
	[1,0,0],
	[1,1,1],
	[0,0,0],
	],
	'L': [
	[0,0,1],
	[1,1,1],
	[0,0,0],
	],
	'O': [
	[1,1],
	[1,1],
	],
	'S': [
	[0,1,1],
	[1,1,0],
	[0,0,0],
	],
	'Z': [
	[1,1,0],
	[0,1,1],
	[0,0,0],
	],
	'T': [
	[0,1,0],
	[1,1,1],
	[0,0,0],
	]
	};

	// color of each tetromino
	const colors = {
	'I': 'cyan',
	'O': 'yellow',
	'T': 'purple',
	'S': 'green',
	'Z': 'red',
	'J': 'blue',
	'L': 'orange'
	};

	let count = 0;
	let tetromino = getNextTetromino();
	let rAF = null; // keep track of the animation frame so we can cancel it
	let gameOver = false;

	// game loop
	function loop() {
	rAF = requestAnimationFrame(loop);
	context.clearRect(0,0,canvas.width,canvas.height);

	// draw the playfield
	for (let row = 0; row < 20; row++) {
	for (let col = 0; col < 10; col++) {
	if (playfield[row][col]) {
	const name = playfield[row][col];
	context.fillStyle = colors[name];

	// drawing 1 px smaller than the grid creates a grid effect
	context.fillRect(col * grid, row * grid, grid-1, grid-1);
	}
	}
	}

	// draw the active tetromino
	if (tetromino) {

	// tetromino falls every 35 frames
	if (++count > 35) {
	tetromino.row++;
	count = 0;

	// place piece if it runs into anything
	if (!isValidMove(tetromino.matrix, tetromino.row, tetromino.col)) {
	tetromino.row--;
	placeTetromino();
	}
	}

	context.fillStyle = colors[tetromino.name];

	for (let row = 0; row < tetromino.matrix.length; row++) {
	for (let col = 0; col < tetromino.matrix[row].length; col++) {
	if (tetromino.matrix[row][col]) {

	// drawing 1 px smaller than the grid creates a grid effect
	context.fillRect((tetromino.col + col) * grid, (tetromino.row + row) * grid, grid-1, grid-1);
	}
	}
	}
	}
	}

	// listen to keyboard events to move the active tetromino
	document.addEventListener('keydown', function(e) {
	if (gameOver) return;

	// left and right arrow keys (move)
	if (e.which === 37 \|\| e.which === 39) {
	const col = e.which === 37
	? tetromino.col - 1
	: tetromino.col + 1;

	if (isValidMove(tetromino.matrix, tetromino.row, col)) {
	tetromino.col = col;
	}
	}

	// up arrow key (rotate)
	if (e.which === 38) {
	const matrix = rotate(tetromino.matrix);
	if (isValidMove(matrix, tetromino.row, tetromino.col)) {
	tetromino.matrix = matrix;
	}
	}

	// down arrow key (drop)
	if(e.which === 40) {
	const row = tetromino.row + 1;

	if (!isValidMove(tetromino.matrix, row, tetromino.col)) {
	tetromino.row = row - 1;

	placeTetromino();
	return;
	}

	tetromino.row = row;
	}
	});

	// start the game
	rAF = requestAnimationFrame(loop);
	</script>
	</body>
	</html>

Tetris Game In Html

Post a Comment

Contact form