Python 贪吃蛇小游戏

（声明：本文使用的源码非原创，17年在CSDN上用币下载的资源，具体是哪位大佬的忘记了）
在此之前首先说一下环境
Python3.X （使用2.x的大佬自己稍微改动一下就行）
pygame 1.9.6（当然这个没必要和我一样）

1. 导包

## 导入相关模块
import random
import pygame
import sys

from pygame.locals import *

2. 配置初始化参数

snake_speed = 15 #贪吃蛇的速度
windows_width = 800
windows_height = 600 #游戏窗口的大小
cell_size = 20       #贪吃蛇身体方块大小,注意身体大小必须能被窗口长宽整除

''' #初始化区
由于我们的贪吃蛇是有大小尺寸的, 因此地图的实际尺寸是相对于贪吃蛇的大小尺寸而言的
'''
map_width = int(windows_width / cell_size)
map_height = int(windows_height / cell_size)

# 颜色定义
white = (255, 255, 255)
black = (0, 0, 0)
gray = (230, 230, 230)
dark_gray = (40, 40, 40)
DARKGreen = (0, 155, 0)
Green = (0, 255, 0)
Red = (255, 0, 0)
blue = (0, 0, 255)
dark_blue =(0,0, 139)


BG_COLOR = black #游戏背景颜色

# 定义方向
UP = 1
DOWN = 2
LEFT = 3
RIGHT = 4

HEAD = 0 #贪吃蛇头部下标

3. 主函数及运行主体

#主函数
def main():
	pygame.init() # 模块初始化
	snake_speed_clock = pygame.time.Clock() # 创建Pygame时钟对象
	screen = pygame.display.set_mode((windows_width, windows_height)) #
	screen.fill(white)

	pygame.display.set_caption("Python 贪吃蛇小游戏") #设置标题
	show_start_info(screen)               #欢迎信息
	while True:
		running_game(screen, snake_speed_clock)
		show_gameover_info(screen)


#游戏运行主体
def running_game(screen,snake_speed_clock):
	startx = random.randint(3, map_width - 8) #开始位置
	starty = random.randint(3, map_height - 8)
	snake_coords = [{
    
    'x': startx, 'y': starty},  #初始贪吃蛇
                  {
    
    'x': startx - 1, 'y': starty},
                  {
    
    'x': startx - 2, 'y': starty}]

	direction = RIGHT       #  开始时向右移动

	food = get_random_location()     #实物随机位置

	while True:
		for event in pygame.event.get():
			if event.type == QUIT:
				terminate()
			elif event.type == KEYDOWN:
				if (event.key == K_LEFT or event.key == K_a) and direction != RIGHT:
					direction = LEFT
				elif (event.key == K_RIGHT or event.key == K_d) and direction != LEFT:
					direction = RIGHT
				elif (event.key == K_UP or event.key == K_w) and direction != DOWN:
					direction = UP
				elif (event.key == K_DOWN or event.key == K_s) and direction != UP:
					direction = DOWN
				elif event.key == K_ESCAPE:
					terminate()

		move_snake(direction, snake_coords) #移动蛇

		ret = snake_is_alive(snake_coords)
		if not ret:
			break #蛇跪了. 游戏结束
		snake_is_eat_food(snake_coords, food) #判断蛇是否吃到食物

		screen.fill(BG_COLOR)
		#draw_grid(screen)
		draw_snake(screen, snake_coords)
		draw_food(screen, food)
		draw_score(screen, len(snake_coords) - 3)
		pygame.display.update()
		snake_speed_clock.tick(snake_speed) #控制fps

4. 画食物的函数

#将食物画出来
def draw_food(screen, food):
	x = food['x'] * cell_size
	y = food['y'] * cell_size
	appleRect = pygame.Rect(x, y, cell_size, cell_size)
	pygame.draw.rect(screen, Red, appleRect)

5. 画贪吃蛇的函数

#将贪吃蛇画出来
def draw_snake(screen, snake_coords):
	for coord in snake_coords:
		x = coord['x'] * cell_size
		y = coord['y'] * cell_size
		wormSegmentRect = pygame.Rect(x, y, cell_size, cell_size)
		pygame.draw.rect(screen, dark_blue, wormSegmentRect)
		wormInnerSegmentRect = pygame.Rect(                #蛇身子里面的第二层亮绿色
			x + 4, y + 4, cell_size - 8, cell_size - 8)
		pygame.draw.rect(screen, blue, wormInnerSegmentRect)

6. 画网格的函数（非必选，觉得多余的可以忽略此项）

#画网格(可选)
def draw_grid(screen):
	for x in range(0, windows_width, cell_size):  # draw 水平 lines
		pygame.draw.line(screen, dark_gray, (x, 0), (x, windows_height))
	for y in range(0, windows_height, cell_size):  # draw 垂直 lines
		pygame.draw.line(screen, dark_gray, (0, y), (windows_width, y))

7. 操纵贪吃蛇移动的函数

#移动贪吃蛇
def move_snake(direction, snake_coords):
    if direction == UP:
        newHead = {
    
    'x': snake_coords[HEAD]['x'], 'y': snake_coords[HEAD]['y'] - 1}
    elif direction == DOWN:
        newHead = {
    
    'x': snake_coords[HEAD]['x'], 'y': snake_coords[HEAD]['y'] + 1}
    elif direction == LEFT:
        newHead = {
    
    'x': snake_coords[HEAD]['x'] - 1, 'y': snake_coords[HEAD]['y']}
    elif direction == RIGHT:
        newHead = {
    
    'x': snake_coords[HEAD]['x'] + 1, 'y': snake_coords[HEAD]['y']}

    snake_coords.insert(0, newHead)

8. 判断蛇是否死亡的函数

#判断蛇死了没
def snake_is_alive(snake_coords):
	tag = True
	if snake_coords[HEAD]['x'] == -1 or snake_coords[HEAD]['x'] == map_width or snake_coords[HEAD]['y'] == -1 or \
			snake_coords[HEAD]['y'] == map_height:
		tag = False # 蛇碰壁啦
	for snake_body in snake_coords[1:]:
		if snake_body['x'] == snake_coords[HEAD]['x'] and snake_body['y'] == snake_coords[HEAD]['y']:
			tag = False # 蛇碰到自己身体啦
	return tag

9.判断蛇是否吃到食物的函数

#判断贪吃蛇是否吃到食物
def snake_is_eat_food(snake_coords, food):  #如果是列表或字典，那么函数内修改参数内容，就会影响到函数体外的对象。
	if snake_coords[HEAD]['x'] == food['x'] and snake_coords[HEAD]['y'] == food['y']:
		food['x'] = random.randint(0, map_width - 1)
		food['y'] = random.randint(0, map_height - 1) # 实物位置重新设置
	else:
		del snake_coords[-1]  # 如果没有吃到实物, 就向前移动, 那么尾部一格删掉

10. 随机生成食物

#食物随机生成
def get_random_location():
	return {
    
    'x': random.randint(0, map_width - 1), 'y': random.randint(0, map_height - 1)}

11. 游戏开始与结束的相关配置

#开始信息显示
def show_start_info(screen):
	font = pygame.font.Font('myfont.ttf', 40)
	tip = font.render('按任意键开始游戏~~~', True, (65, 105, 225))
	gamestart = pygame.image.load('gamestart.png')
	screen.blit(gamestart, (140, 30))
	screen.blit(tip, (240, 550))
	pygame.display.update()

	while True:  #键盘监听事件
		for event in pygame.event.get():  # event handling loop
			if event.type == QUIT:
				terminate()     #终止程序
			elif event.type == KEYDOWN:
				if (event.key == K_ESCAPE):  #终止程序
					terminate() #终止程序
				else:
					return #结束此函数, 开始游戏
#游戏结束信息显示
def show_gameover_info(screen):
	font = pygame.font.Font('myfont.ttf', 40)
	tip = font.render('按Q或者ESC退出游戏, 按任意键重新开始游戏~', True, (65, 105, 225))
	gamestart = pygame.image.load('gameover.png')
	screen.blit(gamestart, (60, 0))
	screen.blit(tip, (80, 300))
	pygame.display.update()

	while True:  #键盘监听事件
		for event in pygame.event.get():  # event handling loop
			if event.type == QUIT:
				terminate()     #终止程序
			elif event.type == KEYDOWN:
				if event.key == K_ESCAPE or event.key == K_q:  #终止程序
					terminate() #终止程序
				else:
					return #结束此函数, 重新开始游戏
#画成绩
def draw_score(screen,score):
	font = pygame.font.Font('myfont.ttf', 30)
	scoreSurf = font.render('得分: %s' % score, True, Green)
	scoreRect = scoreSurf.get_rect()
	scoreRect.topleft = (windows_width - 120, 10)
	screen.blit(scoreSurf, scoreRect)
#程序终止
def terminate():
	pygame.quit()
	sys.exit()