366 lines
11 KiB
JavaScript
Executable File
366 lines
11 KiB
JavaScript
Executable File
class SnakeGame {
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constructor() {
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this.canvas = document.getElementById('gameCanvas');
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this.ctx = this.canvas.getContext('2d');
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// 游戏配置
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this.gridSize = 20;
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this.tileCount = this.canvas.width / this.gridSize;
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this.tileCountY = this.canvas.height / this.gridSize;
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// 蛇的初始状态
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this.snake = [
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{x: 10, y: 10},
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{x: 9, y: 10},
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{x: 8, y: 10}
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];
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// 食物位置
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this.food = {x: 15, y: 15};
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// 游戏状态
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this.dx = 1; // 初始向右移动
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this.dy = 0;
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this.score = 0;
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this.level = 1;
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this.gameSpeed = 10; // 初始速度
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this.isPaused = false;
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this.gameOver = false;
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this.startTime = Date.now();
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this.foodEaten = 0;
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// 特殊食物
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this.specialFood = null;
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this.specialFoodTimer = 0;
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this.specialFoodDuration = 5000; // 5秒
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this.init();
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}
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init() {
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this.generateFood();
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this.gameLoop();
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// 监听键盘事件
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document.addEventListener('keydown', (e) => {
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if (this.isPaused || this.gameOver) return;
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switch(e.key) {
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case 'ArrowUp':
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case 'w':
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case 'W':
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if (this.dy === 0) {
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this.dx = 0;
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this.dy = -1;
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}
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break;
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case 'ArrowDown':
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case 's':
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case 'S':
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if (this.dy === 0) {
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this.dx = 0;
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this.dy = 1;
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}
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break;
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case 'ArrowLeft':
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case 'a':
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case 'A':
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if (this.dx === 0) {
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this.dx = -1;
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this.dy = 0;
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}
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break;
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case 'ArrowRight':
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case 'd':
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case 'D':
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if (this.dx === 0) {
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this.dx = 1;
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this.dy = 0;
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}
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break;
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case ' ':
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this.togglePause();
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break;
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}
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});
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}
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generateFood() {
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// 生成普通食物
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let newFood;
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do {
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newFood = {
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x: Math.floor(Math.random() * this.tileCount),
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y: Math.floor(Math.random() * this.tileCountY)
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};
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} while (this.isPositionOccupied(newFood));
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this.food = newFood;
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// 有10%几率生成特殊食物
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if (Math.random() < 0.1 && !this.specialFood) {
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this.generateSpecialFood();
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}
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}
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generateSpecialFood() {
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let newFood;
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do {
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newFood = {
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x: Math.floor(Math.random() * this.tileCount),
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y: Math.floor(Math.random() * this.tileCountY),
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type: 'special',
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value: 5 // 特殊食物价值5分
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};
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} while (this.isPositionOccupied(newFood));
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this.specialFood = newFood;
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this.specialFoodTimer = Date.now();
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}
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isPositionOccupied(position) {
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// 检查是否与蛇身重叠
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for (let segment of this.snake) {
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if (segment.x === position.x && segment.y === position.y) {
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return true;
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}
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}
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// 检查是否与普通食物重叠
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if (this.food && this.food.x === position.x && this.food.y === position.y) {
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return true;
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}
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// 检查是否与特殊食物重叠
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if (this.specialFood && this.specialFood.x === position.x && this.specialFood.y === position.y) {
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return true;
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}
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return false;
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}
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update() {
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if (this.isPaused || this.gameOver) return;
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// 更新蛇头位置
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const head = {x: this.snake[0].x + this.dx, y: this.snake[0].y + this.dy};
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// 检查游戏结束条件
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if (this.checkCollision(head)) {
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this.gameOver = true;
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this.showGameOver();
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return;
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}
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// 移动蛇
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this.snake.unshift(head);
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// 检查是否吃到食物
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if (head.x === this.food.x && head.y === this.food.y) {
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this.score += 1;
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this.foodEaten++;
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this.generateFood();
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this.updateLevel();
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} else if (this.specialFood && head.x === this.specialFood.x && head.y === this.specialFood.y) {
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this.score += this.specialFood.value;
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this.foodEaten++;
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this.specialFood = null;
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this.generateFood();
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this.updateLevel();
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} else {
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this.snake.pop(); // 如果没有吃到食物，移除尾部
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}
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// 检查特殊食物超时
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if (this.specialFood && Date.now() - this.specialFoodTimer > this.specialFoodDuration) {
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this.specialFood = null;
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}
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// 更新UI
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this.updateUI();
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}
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checkCollision(head) {
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// 检查撞墙
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if (head.x < 0 || head.x >= this.tileCount || head.y < 0 || head.y >= this.tileCountY) {
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return true;
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}
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// 检查撞到自己（从第4节开始检查，避免误判）
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for (let i = 4; i < this.snake.length; i++) {
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if (this.snake[i].x === head.x && this.snake[i].y === head.y) {
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return true;
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}
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}
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return false;
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}
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updateLevel() {
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// 每吃5个食物升一级
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const newLevel = Math.floor(this.foodEaten / 5) + 1;
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if (newLevel > this.level) {
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this.level = newLevel;
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this.gameSpeed = Math.min(20, 10 + this.level); // 速度上限20
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}
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}
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updateUI() {
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document.getElementById('score').textContent = this.score;
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document.getElementById('length').textContent = this.snake.length;
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document.getElementById('level').textContent = this.level;
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}
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draw() {
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// 清空画布
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this.ctx.fillStyle = '#222';
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this.ctx.fillRect(0, 0, this.canvas.width, this.canvas.height);
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// 绘制网格（背景）
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this.ctx.strokeStyle = '#333';
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this.ctx.lineWidth = 0.5;
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for (let x = 0; x < this.tileCount; x++) {
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for (let y = 0; y < this.tileCountY; y++) {
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this.ctx.strokeRect(x * this.gridSize, y * this.gridSize, this.gridSize, this.gridSize);
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}
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}
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// 绘制蛇
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this.snake.forEach((segment, index) => {
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if (index === 0) {
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// 蛇头
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this.ctx.fillStyle = '#4CAF50';
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} else {
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// 蛇身，渐变颜色
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const gradient = (index / this.snake.length) * 100;
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this.ctx.fillStyle = `hsl(120, 80%, ${60 - gradient}%)`;
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}
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this.ctx.fillRect(segment.x * this.gridSize, segment.y * this.gridSize, this.gridSize, this.gridSize);
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// 边框
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this.ctx.strokeStyle = '#2E7D32';
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this.ctx.strokeRect(segment.x * this.gridSize, segment.y * this.gridSize, this.gridSize, this.gridSize);
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});
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// 绘制普通食物
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this.ctx.fillStyle = '#FF5252';
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this.ctx.beginPath();
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this.ctx.arc(
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this.food.x * this.gridSize + this.gridSize / 2,
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this.food.y * this.gridSize + this.gridSize / 2,
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this.gridSize / 2 - 2,
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0,
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Math.PI * 2
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);
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this.ctx.fill();
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// 绘制特殊食物（如果存在）
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if (this.specialFood) {
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this.ctx.fillStyle = '#FFD700';
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this.ctx.beginPath();
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this.ctx.arc(
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this.specialFood.x * this.gridSize + this.gridSize / 2,
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this.specialFood.y * this.gridSize + this.gridSize / 2,
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this.gridSize / 2 - 1,
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0,
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Math.PI * 2
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);
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this.ctx.fill();
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// 闪烁效果
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const time = Date.now() - this.specialFoodTimer;
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const alpha = 0.5 + 0.5 * Math.sin(time / 200);
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this.ctx.globalAlpha = alpha;
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this.ctx.fillStyle = '#FF6B00';
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this.ctx.fill();
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this.ctx.globalAlpha = 1;
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}
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// 绘制暂停状态
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if (this.isPaused) {
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this.ctx.fillStyle = 'rgba(0, 0, 0, 0.7)';
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this.ctx.fillRect(0, 0, this.canvas.width, this.canvas.height);
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this.ctx.fillStyle = 'white';
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this.ctx.font = '24px Arial';
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this.ctx.textAlign = 'center';
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this.ctx.fillText('游戏暂停', this.canvas.width / 2, this.canvas.height / 2);
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}
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}
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gameLoop() {
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this.update();
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this.draw();
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if (!this.gameOver) {
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setTimeout(() => this.gameLoop(), 1000 / this.gameSpeed);
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}
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}
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togglePause() {
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this.isPaused = !this.isPaused;
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document.getElementById('pauseBtn').textContent = this.isPaused ? '继续' : '暂停';
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if (!this.isPaused && !this.gameOver) {
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this.gameLoop();
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}
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}
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changeDirection(dx, dy) {
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if (this.isPaused || this.gameOver) return;
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// 防止180度转弯
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if ((this.dx !== 0 && dx !== 0) || (this.dy !== 0 && dy !== 0)) {
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return;
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}
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this.dx = dx;
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this.dy = dy;
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}
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showGameOver() {
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const modal = document.getElementById('gameOverModal');
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const gameTime = Math.floor((Date.now() - this.startTime) / 1000);
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document.getElementById('finalScore').textContent = this.score;
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document.getElementById('finalLength').textContent = this.snake.length;
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document.getElementById('finalLevel').textContent = this.level;
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document.getElementById('gameTime').textContent = gameTime;
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document.getElementById('foodEaten').textContent = this.foodEaten;
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modal.style.display = 'flex';
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}
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restart() {
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this.snake = [
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{x: 10, y: 10},
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{x: 9, y: 10},
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{x: 8, y: 10}
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];
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this.dx = 1;
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this.dy = 0;
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this.score = 0;
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this.level = 1;
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this.gameSpeed = 10;
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this.isPaused = false;
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this.gameOver = false;
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this.startTime = Date.now();
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this.foodEaten = 0;
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this.specialFood = null;
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this.generateFood();
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this.updateUI();
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document.getElementById('gameOverModal').style.display = 'none';
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document.getElementById('pauseBtn').textContent = '暂停';
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this.gameLoop();
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}
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}
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// 全局游戏实例
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let game;
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document.addEventListener('DOMContentLoaded', () => {
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game = new SnakeGame();
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}); |