python写一个贪吃蛇小游戏

好的，我来写一个简单的贪吃蛇小游戏，需要用到 Python 的 Pygame 库。

首先安装 Pygame 库，在命令行中输入：

pip install pygame

然后创建一个 Python 文件，比如命名为 `snake_game.py`，并在文件中写入以下代码：

import pygame
import random

# 初始化 Pygame
pygame.init()

# 游戏窗口大小
WINDOW_WIDTH = 800
WINDOW_HEIGHT = 600

# 创建游戏窗口
screen = pygame.display.set_mode((WINDOW_WIDTH, WINDOW_HEIGHT))

# 设置窗口标题
pygame.display.set_caption("贪吃蛇小游戏")

# 定义颜色
BLACK = (0, 0, 0)
WHITE = (255, 255, 255)
GREEN = (0, 255, 0)
RED = (255, 0, 0)

# 定义游戏区域大小和格子大小
GAME_AREA_WIDTH = 600
GAME_AREA_HEIGHT = 600
GRID_SIZE = 20

# 计算出格子的行数和列数
GRID_ROWS = GAME_AREA_HEIGHT // GRID_SIZE
GRID_COLS = GAME_AREA_WIDTH // GRID_SIZE

# 定义贪吃蛇初始位置和长度
SNAKE_INIT_POS = [(GRID_COLS // 2, GRID_ROWS // 2)]
SNAKE_INIT_LENGTH = 3

# 定义贪吃蛇的移动速度
SNAKE_SPEED = 5

# 定义食物的初始位置
FOOD_INIT_POS = (random.randint(0, GRID_COLS - 1), random.randint(0, GRID_ROWS - 1))

# 加载字体
font = pygame.font.SysFont(None, 30)

# 定义游戏结束的函数
def game_over():
    text = font.render("Game Over", True, RED)
    screen.blit(text, (WINDOW_WIDTH // 2 - text.get_width() // 2, WINDOW_HEIGHT // 2 - text.get_height() // 2))
    pygame.display.update()
    pygame.time.wait(1000)

# 定义绘制游戏区域的函数
def draw_game_area():
    pygame.draw.rect(screen, WHITE, (100, 50, GAME_AREA_WIDTH, GAME_AREA_HEIGHT), 2)

# 定义绘制贪吃蛇的函数
def draw_snake(snake):
    for pos in snake:
        pygame.draw.rect(screen, GREEN, (100 + pos[0] * GRID_SIZE, 50 + pos[1] * GRID_SIZE, GRID_SIZE, GRID_SIZE))

# 定义绘制食物的函数
def draw_food(food):
    pygame.draw.rect(screen, RED, (100 + food[0] * GRID_SIZE, 50 + food[1] * GRID_SIZE, GRID_SIZE, GRID_SIZE))

# 定义更新贪吃蛇的函数
def update_snake(snake, direction):
    head_x, head_y = snake[0]
    if direction == "UP":
        head_y -= 1
    elif direction == "DOWN":
        head_y += 1
    elif direction == "LEFT":
        head_x -= 1
    elif direction == "RIGHT":
        head_x += 1
    snake.insert(0, (head_x, head_y))
    if len(snake) > SNAKE_INIT_LENGTH:
        snake.pop()
    return snake

# 定义检测贪吃蛇是否碰到边界或自己的函数
def check_collision(snake):
    head_x, head_y = snake[0]
    if head_x < 0 or head_x >= GRID_COLS or head_y < 0 or head_y >= GRID_ROWS:
        return True
    for pos in snake[1:]:
        if pos == (head_x, head_y):
            return True
    return False

# 游戏循环
def game_loop():
    # 初始化贪吃蛇和食物
    snake = SNAKE_INIT_POS.copy()
    food = FOOD_INIT_POS
    direction = "RIGHT"
    score = 0

    # 游戏是否结束的标志
    game_over_flag = False

    # 游戏循环
    while not game_over_flag:
        # 处理事件
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                game_over_flag = True
            elif event.type == pygame.KEYDOWN:
                if event.key == pygame.K_UP and direction != "DOWN":
                    direction = "UP"
                elif event.key == pygame.K_DOWN and direction != "UP":
                    direction = "DOWN"
                elif event.key == pygame.K_LEFT and direction != "RIGHT":
                    direction = "LEFT"
                elif event.key == pygame.K_RIGHT and direction != "LEFT":
                    direction = "RIGHT"

        # 清屏
        screen.fill(BLACK)

        # 绘制游戏区域和网格
        draw_game_area()
        for i in range(GRID_ROWS):
            pygame.draw.line(screen, WHITE, (100, 50 + i * GRID_SIZE), (100 + GAME_AREA_WIDTH, 50 + i * GRID_SIZE))
        for i in range(GRID_COLS):
            pygame.draw.line(screen, WHITE, (100 + i * GRID_SIZE, 50), (100 + i * GRID_SIZE, 50 + GAME_AREA_HEIGHT))

        # 绘制贪吃蛇和食物
        draw_snake(snake)
        draw_food(food)

        # 更新贪吃蛇
        snake = update_snake(snake, direction)

        # 检测贪吃蛇是否吃到食物
        if snake[0] == food:
            food = (random.randint(0, GRID_COLS - 1), random.randint(0, GRID_ROWS - 1))
            score += 1
            SNAKE_INIT_LENGTH += 1

        # 检测贪吃蛇是否碰到边界或自己
        if check_collision(snake):
            game_over()
            game_over_flag = True

        # 更新分数
        score_text = font.render("Score: {}".format(score), True, WHITE)
        screen.blit(score_text, (10, 10))

        # 更新屏幕
        pygame.display.update()

        # 控制游戏帧率
        pygame.time.Clock().tick(SNAKE_SPEED)

    # 退出 Pygame
    pygame.quit()

# 开始游戏
game_loop()

代码中的注释会帮助你理解每个部分的作用。运行 `snake_game.py` 文件即可开始游戏。