核心内容

1.创建食物、蛇身

2.刷新展示屏幕

3.检测pygame.event

4.改变方向的实现逻辑

5.检测碰撞以及超出范围

6.死亡重置

Code

import os
import random
import pygame

# 屏幕大小
SCREEN_X = 600
SCREEN_Y = 600


def main():
    # 初始化pygame
    pygame.init()
    screen_size = (SCREEN_X, SCREEN_Y)
    screen = pygame.display.set_mode(screen_size)
    # 设置窗口名
    pygame.display.set_caption('贪吃蛇---by斌')
    # 创建一个clock对象来跟踪时间
    clock = pygame.time.Clock()
    # 初始化得分
    scores = 0
    # 初始化存活状态
    isdead = False
    # 创建snake实例
    snake = Snake()
    # 创建food实例
    food = Food()

    while True:
        for event in pygame.event.get():
            # 检测退出
            if event.type == pygame.QUIT:
                os._exit(0)

            if event.type == pygame.KEYDOWN:
                snake.changedirection(event.key)
                # 死亡后空格重新开始
                if event.key == pygame.K_SPACE and isdead:
                    return main()
                # 死亡后Esc退出
                elif event.key == pygame.K_ESCAPE and isdead:
                    os._exit(0)
                    
        # 设置屏幕背景颜色
        screen.fill((255, 255, 255))

        # 未死亡则向前移动
        if not isdead: 
            snake.move()
            
        # 刷新蛇身
        for rect in snake.body:
            pygame.draw.rect(screen, (20, 100, 30), rect, 0)

        isdead = snake.isdead()

        # 死亡后展示文本
        if isdead:
            scores_num = []
            # 寻找最高得分
            with open('scores.txt', 'r') as file:
                file.seek(0, 0)
                scores_str = file.readlines()
                for x in scores_str:
                    scores_num.append(int(x))
                best_scores = max(scores_num)
            show_text(screen, (125, 200), 'YOU DEAD', (227, 29, 18), False, 100)
            show_text(screen, (230, 260), "Best Score:{}".format(best_scores), (22, 220, 22), False, 30)
            show_text(screen, (185, 290), "press 'Spcae' to try again", (0, 0, 22), False, 30)
            show_text(screen, (230, 310), "or 'Esc' to exit", (0, 0, 22), False, 30)

        # 检测吃到食物
        if food.rect == snake.body[0]:
            # 吃到食物后加1分
            scores += 1
            # 储存历史得分
            with open('scores.txt', 'a+') as file:
                file.write(str(scores) + '\n')
                file.flush()
                file.close()
            # 吃到食物后移除原食物且蛇身增加
            food.remove()
            snake.addnode()
            
        # 重新生成食物
        food.set()
        # 刷新食物
        pygame.draw.rect(screen, (136, 0, 24), food.rect)
        
        #展示积分
        show_text(screen, (50, 500), "Scores:" + str(scores), (233, 233, 233))
        
        # 按时刷新
        pygame.display.update()
        clock.tick(10)


class Snake(object):
    def __init__(self):
        # 规定初始方向为右
        self.direction = pygame.K_RIGHT
        self.body = []
        for x in range(5):
            self.addnode()

    def addnode(self):
        # 初始坐标
        left, top = (0, 0)
        if self.body:
            left, top = (self.body[0].left, self.body[0].top)
            
        # 创建蛇身并规定大小
        node = pygame.Rect(left, top, 25, 25)

        # 检测按键
        if self.direction == pygame.K_LEFT:
            node.left -= 25
        elif self.direction == pygame.K_RIGHT:
            node.left += 25
        elif self.direction == pygame.K_UP:
            node.top -= 25
        elif self.direction == pygame.K_DOWN:
            node.top += 25
        self.body.insert(0, node)

    def delnode(self):
        self.body.pop()

    def isdead(self): # 检测死亡
        # 检测超出屏幕
        if self.body[0].x not in range(SCREEN_X):
            return True
        if self.body[0].y not in range(SCREEN_Y):
            return True
        
        # 检测身体碰撞
        if self.body[0] in self.body[1:]:
            return True
        return False

    def move(self): # 向前移动
        self.addnode()
        self.delnode()

    def changedirection(self, curkey): #改变方向
        lr = [pygame.K_LEFT, pygame.K_RIGHT]
        ud = [pygame.K_UP, pygame.K_DOWN]
        if curkey in (lr + ud):
            if (curkey in lr) and (self.direction in lr):
                return
            if (curkey in ud) and (self.direction in ud):
                return
            self.direction = curkey


class Food: #食物
    def __init__(self):
        # 创建食物并规定大小
        self.rect = pygame.Rect(-25, 0, 25, 25)

    def remove(self):
        # 移除食物
        self.rect.x = -25 

    def set(self):
        # 移除食物后在随机位置重新生成
        if self.rect.x == -25:
            allpos = []
            for pos in range(25, SCREEN_X - 25, 25):
                allpos.append(pos)
            self.rect.left = random.choice(allpos)
            self.rect.top = random.choice(allpos)


def show_text(screen, pos, text, color, font_bold=False,
              font_size=50, font_italic=False): # 设置展示文本
    cur_font = pygame.font.SysFont('宋体', font_size)
    cur_font.set_bold(font_bold)
    cur_font.set_italic(font_italic)
    text_fmt = cur_font.render(text, True, color)
    screen.blit(text_fmt, pos)


if __name__ == "__main__":
    main()

预览效果