Simple HTML Tetris Game: A Step-by-Step Guide
Simple HTML Tetris Game: A Step-by-Step Guide
This document will outline the steps to create a simple game of Tetris using HTML, CSS, and JavaScript.
Step 1: Set up the HTML Document
Create a new HTML document with a basic structure. Inside the
tag, add a<!DOCTYPE html>
<html>
<head>
<title>Simple HTML Tetris Game</title>
</head>
<body>
<div id='game-board'></div>
</body>
</html>
Step 2: Style the Game Board
Add some basic CSS to make the game board look like a grid. Set the width and height of the game board to 300px, and add a border to the div element.
#game-board {
width: 300px;
height: 300px;
border: 1px solid black;
}
Step 3: Create the Game Logic
In the JavaScript file, we will create the game logic. We will start by creating an array to represent the game board. Each element of the array will be an object representing a square on the board. We will also create an object to represent the current piece and its position on the board.
const gameBoard = [];
const currentPiece = {
type: '',
position: [],
};
Next, we will create a function to initialize the game board. This function will loop through each row and column of the board and create a new square object for each one.
function initGameBoard() {
for (let i = 0; i < 20; i++) {
const row = [];
for (let j = 0; j < 10; j++) {
const square = {
x: j,
y: i,
color: '',
};
row.push(square);
}
gameBoard.push(row);
}
}
We will also create a function to render the game board on the screen. This function will loop through each square object in the game board array and create a new div element for each one. It will set the background color of the div element to the color of the square object.
function renderGameBoard() {
const board = document.querySelector('#game-board');
for (let i = 0; i < gameBoard.length; i++) {
for (let j = 0; j < gameBoard[i].length; j++) {
const square = gameBoard[i][j];
const div = document.createElement('div');
div.style.width = '30px';
div.style.height = '30px';
div.style.backgroundColor = square.color;
board.appendChild(div);
}
}
}
Step 4: Add User Input
We will use the arrow keys to move the current piece left and right on the game board. We will create an event listener for the keydown event and use a switch statement to handle the arrow key input.
document.addEventListener('keydown', (event) => {
switch (event.key) {
case 'ArrowLeft':
// Move current piece left
break;
case 'ArrowRight':
// Move current piece right
break;
}
});
Step 5: Move the Current Piece
We will create functions to move the current piece left and right on the game board. These functions will update the position of the current piece object and update the color of the game board squares to reflect the new position of the piece.
function moveLeft() {
currentPiece.position.forEach((square) => {
square.x--;
});
updateGameBoard();
}
function moveRight() {
currentPiece.position.forEach((square) => {
square.x++;
});
updateGameBoard();
}
function updateGameBoard() {
for (let i = 0; i < gameBoard.length; i++) {
for (let j = 0; j < gameBoard[i].length; j++) {
const square = gameBoard[i][j];
square.color = '';
}
}
currentPiece.position.forEach((square) => {
gameBoard[square.y][square.x].color = currentPiece.color;
});
renderGameBoard();
}
Step 6: Create the Tetromino Pieces
We will create an object for each type of tetromino piece. Each object will have a color and an array of positions for each square of the piece.
const tetrominoPieces = {
i: {
color: 'cyan',
position: [
{ x: 3, y: 0 },
{ x: 4, y: 0 },
{ x: 5, y: 0 },
{ x: 6, y: 0 },
],
},
j: {
color: 'blue',
position: [
{ x: 4, y: 0 },
{ x: 4, y: 1 },
{ x: 5, y: 1 },
{ x: 6, y: 1 },
],
},
l: {
color: 'orange',
position: [
{ x: 6, y: 0 },
{ x: 4, y: 1 },
{ x: 5, y: 1 },
{ x: 6, y: 1 },
],
},
o: {
color: 'yellow',
position: [
{ x: 4, y: 0 },
{ x: 5, y: 0 },
{ x: 4, y: 1 },
{ x: 5, y: 1 },
],
},
s: {
color: 'lime',
position: [
{ x: 5, y: 0 },
{ x: 6, y: 0 },
{ x: 4, y: 1 },
{ x: 5, y: 1 },
],
},
t: {
color: 'purple',
position: [
{ x: 4, y: 0 },
{ x: 5, y: 0 },
{ x: 6, y: 0 },
{ x: 5, y: 1 },
],
},
z: {
color: 'red',
position: [
{ x: 4, y: 0 },
{ x: 5, y: 0 },
{ x: 5, y: 1 },
{ x: 6, y: 1 },
],
},
};
Step 7: Randomly Select a Tetromino Piece
We will create a function to randomly select a tetromino piece from the tetrominoPieces object. This function will return a new currentPiece object with the color and position of the selected piece.
function getRandomPiece() {
const tetrominoKeys = Object.keys(tetrominoPieces);
const randomKey = tetrominoKeys[Math.floor(Math.random() * tetrominoKeys.length)];
const piece = tetrominoPieces[randomKey];
const currentPiece = {
type: randomKey,
color: piece.color,
position: piece.position,
};
return currentPiece;
}
Step 8: Start the Game
We will create a function to start the game. This function will initialize the game board, render the game board on the screen, and start a game loop. The game loop will use setInterval to update the game board every 500 milliseconds.
function startGame() {
initGameBoard();
renderGameBoard();
currentPiece = getRandomPiece();
updateGameBoard();
setInterval(() => {
moveDown();
}, 500);
}
Step 9: Move the Current Piece Down
We will create a function to move the current piece down on the game board. This function will update the position of the current piece object and update the color of the game board squares to reflect the new position of the piece. If the piece reaches the bottom of the game board or collides with another piece, we will create a new current piece and update the game board.
function moveDown() {
currentPiece.position.forEach((square) => {
square.y++;
});
if (checkCollision()) {
currentPiece.position.forEach((square) => {
square.y--;
gameBoard[square.y][square.x].color = currentPiece.color;
});
currentPiece = getRandomPiece();
}
updateGameBoard();
}
function checkCollision() {
const squares = currentPiece.position;
for (let i = 0; i < squares.length; i++) {
const square = squares[i];
if (square.y >= 20) {
return true;
}
if (gameBoard[square.y][square.x].color !== '') {
return true;
}
}
return false;
}
Step 10: Play the Game
Call the startGame() function to play the game.
startGame();
Congratulations! You have created a simple HTML Tetris game. You can continue to add features to the game, such as keeping score and adding levels. Have fun playing!
原文地址: https://www.cveoy.top/t/topic/lmj0 著作权归作者所有。请勿转载和采集!