Python “贪吃蛇”游戏，在不断改进中学习pygame编程

偏执的太偏执、 2023-10-14 22:44 79阅读 0赞

![1ae28d15992f405bb7fd51daa60c3dc2.gif][]

**目录**

前言

改进过程一

增加提示信息

原版帮助摘要

pygame.draw

pygame.font

class Rect

class Surface

改进过程二

增加显示得分

改进过程三

增加背景景乐

增加提示音效

音乐切换

静音切换

mixer.music.play 注意事项

原版帮助摘要

pygame.mixer

pygame.mixer.Sound

改进过程四

增加WASD方向键

增加退出事件的确认

小结

pygame编程框架

完整代码

--------------------

## 前言 ##

在上一篇博文里，从讯飞星火中获取到游戏“贪吃蛇”的代码，运行效果如上图。代码并不完整，当蛇死了就退出游戏，不能多次玩这个游戏。

前文链接：

[讯飞星火、文心一言和通义千问同时编“贪吃蛇”游戏，谁会胜出？][Link 1]

代码如下：

import pygame
    import sys
    import random
     
    # 定义颜色
    WHITE = (255, 255, 255)
    GREEN = (0, 255, 0)
    RED  = (255, 0, 0)
    GREY = (211, 211, 211)  # 淡灰色
     
    def init():
        global screen, screen_size
        global snake_pos, food_pos, snake_speed
     
        # 初始化pygame
        pygame.init()
     
        # 设置屏幕大小
        screen_size = (640, 480)
        screen = pygame.display.set_mode(screen_size)
     
        # 设置游戏标题
        pygame.display.set_caption("贪吃蛇")
     
        # 蛇的初始位置
        snake_pos = [[100, 100], [80, 100], [60, 100]]
     
        # 食物的初始位置
        food_pos = [300, 300]
     
        # 蛇的初始速度
        snake_speed = [20, 0]
     
    def repaint():
        # 绘制游戏界面
        screen.fill(WHITE)
     
        # 定义线段的端点坐标
        x,y = (-1,640,640,-1)*16, []
        for i in range(36):
            for _ in range(2):
                y.append(19+i*20)
     
        # 使用pygame.draw.lines()函数绘制线段
        points = list(zip(x,y))
        pygame.draw.lines(screen, GREY, False, points, 1) # 线宽为1
        points = list(zip(y,x))
        pygame.draw.lines(screen, GREY, False, points, 1)   
     
        # 重画蛇和食物
        for pos in snake_pos:
            pygame.draw.rect(screen, GREEN, pygame.Rect(pos[0], pos[1], 20, 20))
        pygame.draw.rect(screen, RED, pygame.Rect(food_pos[0], food_pos[1], 20, 20))
        pygame.display.flip()
     
    def game_quit():
        pygame.quit()
        sys.exit()
     
    def main():
        global screen, screen_size
        global snake_pos, food_pos, snake_speed
        
        # 主循环
        while True:
            # 处理游戏事件
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    game_quit()
                elif event.type == pygame.KEYDOWN:
                    if event.key == pygame.K_UP:
                        snake_speed = [0, -20]
                    elif event.key == pygame.K_DOWN:
                        snake_speed = [0, 20]
                    elif event.key == pygame.K_LEFT:
                        snake_speed = [-20, 0]
                    elif event.key == pygame.K_RIGHT:
                        snake_speed = [20, 0]
     
            # 更新蛇的位置
            snake_pos.insert(0, [snake_pos[0][0] + snake_speed[0], snake_pos[0][1] + snake_speed[1]])
     
            # 检查蛇头是否碰到食物
            if snake_pos[0] == food_pos:
                food_pos = [random.randrange(1, screen_size[0] // 20) * 20, random.randrange(1, screen_size[1] // 20) * 20]
            else:
                snake_pos.pop()
     
            # 检查蛇头是否碰到墙壁或者蛇身
            if snake_pos[0][0] < 0 or snake_pos[0][0] >= screen_size[0] or snake_pos[0][1] < 0 or snake_pos[0][1] >= screen_size[1] or snake_pos[0] in snake_pos[1:]:
                game_quit()
                '''
                此处可增加与用户的交互，如：
                if askyesno('title','again?'):
                    init() # Yes to Play again
                else:
                    game_quit() # No to Exit
                '''
     
            # 重画界面及蛇和食物
            repaint()
     
            # 控制游戏速度
            pygame.time.Clock().tick(10)
     
    if __name__ == "__main__":
     
        init()
        main()

### 改进过程一 ###

#### 增加提示信息 ####

之前没有仔细学过pygame的编程，刚好拿这例程练练手，在不断改进中学习pygame编程。

原代码一执行，蛇就开始游动了，就从这里入手。开始前，增加显示“按任意键开始...”的提示。

![430570d634af43d699af3c431b6ec93f.png][]

蛇死后，提醒是否重来？Yes to play again, No to quit game.

![f38182e16948453488d737293b8d5fc4.png][]

同时，在游戏中允许按ESC键暂停游戏，再按一次继续。

![3768406c79d048bd9914ae50ed9c4ab9.png][]

由于没查到 pygame 有弹出信息窗口的方法(函数)，于是用了DOS时代显示信息窗口的办法，画多个矩形窗口来模拟窗口，最后在矩形框上写上提示文字。代码如下：

def show\_msg(msg, color = BLUE):  
x = screen.get\_rect().centerx  
y = screen.get\_rect().centery - 50  
font = pygame.font.Font(None, 36)  
text = font.render(msg, True, color)  
text\_rect = text.get\_rect()  
text\_rect.centerx = x  
text\_rect.centery = y  
rectangle1 = pygame.Rect(x-155, y-25, 320, 60)  
rectangle2 = pygame.Rect(x-160, y-30, 320, 60)  
pygame.draw.rect(screen, DARK, rectangle1)  
pygame.draw.rect(screen, GREY, rectangle2)  
pygame.draw.rect(screen, BLACK, rectangle2, 2) \# 边框宽为2  
screen.blit(text, text\_rect)  
pygame.display.flip()

--------------------

#### 原版帮助摘要 ####

##### **pygame.draw** #####

NAME  
pygame.draw - pygame module for drawing shapes

FUNCTIONS  
aaline(...)  
aaline(surface, color, start\_pos, end\_pos) -> Rect  
aaline(surface, color, start\_pos, end\_pos, blend=1) -> Rect  
draw a straight antialiased line  
  
aalines(...)  
aalines(surface, color, closed, points) -> Rect  
aalines(surface, color, closed, points, blend=1) -> Rect  
draw multiple contiguous straight antialiased line segments  
  
arc(...)  
arc(surface, color, rect, start\_angle, stop\_angle) -> Rect  
arc(surface, color, rect, start\_angle, stop\_angle, width=1) -> Rect  
draw an elliptical arc  
  
circle(...)  
circle(surface, color, center, radius) -> Rect  
circle(surface, color, center, radius, width=0, draw\_top\_right=None, draw\_top\_left=None, draw\_bottom\_left=None, draw\_bottom\_right=None) -> Rect  
draw a circle  
  
ellipse(...)  
ellipse(surface, color, rect) -> Rect  
ellipse(surface, color, rect, width=0) -> Rect  
draw an ellipse  
  
line(...)  
line(surface, color, start\_pos, end\_pos) -> Rect  
line(surface, color, start\_pos, end\_pos, width=1) -> Rect  
draw a straight line  
  
**lines(...)**  
lines(surface, color, closed, points) -> Rect  
lines(surface, color, closed, points, width=1) -> Rect  
draw multiple contiguous straight line segments  
  
polygon(...)  
polygon(surface, color, points) -> Rect  
polygon(surface, color, points, width=0) -> Rect  
draw a polygon  
  
**rect(...)**  
rect(surface, color, rect) -> Rect  
rect(surface, color, rect, width=0, border\_radius=0, border\_top\_left\_radius=-1, border\_top\_right\_radius=-1, border\_bottom\_left\_radius=-1, border\_bottom\_right\_radius=-1) -> Rect  
draw a rectangle

--------------------

##### **pygame.font** #####

NAME  
pygame.font - pygame module for loading and rendering fonts

CLASSES  
builtins.object  
Font  
  
class Font(builtins.object)  
| **Font(file\_path=None, size=12) -> Font**  
| Font(file\_path, size) -> Font  
| Font(pathlib.Path, size) -> Font  
| Font(object, size) -> Font  
| create a new Font object from a file  
|  
| Methods defined here:  
|  
| \_\_init\_\_(self, /, \*args, \*\*kwargs)  
| Initialize self. See help(type(self)) for accurate signature.  
|  
| get\_ascent(...)  
| get\_ascent() -> int  
| get the ascent of the font  
|  
| get\_bold(...)  
| get\_bold() -> bool  
| check if text will be rendered bold  
|  
| get\_descent(...)  
| get\_descent() -> int  
| get the descent of the font  
|  
| get\_height(...)  
| get\_height() -> int  
| get the height of the font  
|  
| get\_italic(...)  
| get\_italic() -> bool  
| check if the text will be rendered italic  
|  
| get\_linesize(...)  
| get\_linesize() -> int  
| get the line space of the font text  
|  
| get\_strikethrough(...)  
| get\_strikethrough() -> bool  
| check if text will be rendered with a strikethrough  
|  
| get\_underline(...)  
| get\_underline() -> bool  
| check if text will be rendered with an underline  
|  
| metrics(...)  
| metrics(text) -> list  
| gets the metrics for each character in the passed string  
|  
| **render(...)**  
| render(text, antialias, color, background=None) -> Surface  
| draw text on a new Surface  
|  
| set\_bold(...)  
| set\_bold(bool) -> None  
| enable fake rendering of bold text  
|  
| set\_italic(...)  
| set\_italic(bool) -> None  
| enable fake rendering of italic text  
|  
| set\_script(...)  
| set\_script(str) -> None  
| set the script code for text shaping  
|  
| set\_strikethrough(...)  
| set\_strikethrough(bool) -> None  
| control if text is rendered with a strikethrough  
|  
| set\_underline(...)  
| set\_underline(bool) -> None  
| control if text is rendered with an underline  
|  
| size(...)  
| size(text) -> (width, height)  
| determine the amount of space needed to render text  
|  
| ----------------------------------------------------------------------  
| Data descriptors defined here:  
|  
| bold  
| bold -> bool  
| Gets or sets whether the font should be rendered in (faked) bold.  
|  
| italic  
| italic -> bool  
| Gets or sets whether the font should be rendered in (faked) italics.  
|  
| strikethrough  
| strikethrough -> bool  
| Gets or sets whether the font should be rendered with a strikethrough.  
|  
| underline  
| underline -> bool  
| Gets or sets whether the font should be rendered with an underline.

--------------------

##### **class Rect** #####

Help on class Rect in module pygame.rect:

--------------------

##### **class Surface** #####

--------------------

另外增加了3个状态变量，初始状态为：

is\_running = False  
is\_paused = False  
is\_dead = False

增加了4个按键判别：

is\_dead时，判断重新开始还是退出游戏

pygame.K\_y: 字母Y/y  
pygame.K\_n: 字母N/n

暂停和恢复

pygame.K\_ESCAPE: Esc键  
pygame.K\_SPACE: 空格键

**完整代码如下：**

import pygame
    import sys
    import random
    
    # 定义颜色
    BLACK = (0, 0, 0)
    WHITE = (255, 255, 255)
    RED   = (255, 0, 0)
    GREEN = (0, 255, 0)
    BLUE  = (0, 0, 255)
    GREY  = (220, 220, 220)  # 淡灰色
    DARK  = (120, 120, 120)  # 深灰色
    
    def init():
        global screen, screen_size
        global snake_pos, food_pos, snake_speed
    
        # 初始化pygame
        pygame.init()
    
        # 设置屏幕大小
        screen_size = (640, 480)
        screen = pygame.display.set_mode(screen_size)
    
        # 设置游戏标题
        pygame.display.set_caption("贪吃蛇")
    
        # 蛇的初始位置
        snake_pos = [[100, 100], [80, 100], [60, 100]]
    
        # 食物的初始位置
        food_pos = [300, 300]
    
        # 蛇的初始速度
        snake_speed = [20, 0]
    
    
    def show_msg(msg, color = BLUE):
        x = screen.get_rect().centerx
        y = screen.get_rect().centery - 50
        font = pygame.font.Font(None, 36)
        text = font.render(msg, True, color)
        text_rect = text.get_rect()
        text_rect.centerx = x
        text_rect.centery = y
        rectangle1 = pygame.Rect(x-155, y-25, 320, 60)
        rectangle2 = pygame.Rect(x-160, y-30, 320, 60)
        pygame.draw.rect(screen, DARK, rectangle1)
        pygame.draw.rect(screen, GREY, rectangle2)
        pygame.draw.rect(screen, BLACK, rectangle2, 2) # 边框宽为2
        screen.blit(text, text_rect)
        pygame.display.flip()
    
    def repaint():
        # 绘制游戏界面
        screen.fill(WHITE)
    
        # 定义线段的端点坐标
        x,y = (-1,640,640,-1)*16, []
        for i in range(36):
            for _ in range(2):
                y.append(19+i*20)
    
        # 使用pygame.draw.lines()函数绘制线段
        points = list(zip(x,y))
        pygame.draw.lines(screen, GREY, False, points, 1) # 线宽为1
        points = list(zip(y,x))
        pygame.draw.lines(screen, GREY, False, points, 1)   
    
        # 重画蛇和食物
        for pos in snake_pos:
            pygame.draw.rect(screen, GREEN, pygame.Rect(pos[0], pos[1], 20, 20))
        pygame.draw.rect(screen, RED, pygame.Rect(food_pos[0], food_pos[1], 20, 20))
        pygame.display.flip()
    
    def game_quit():
        pygame.quit()
        sys.exit()
    
    def main():
        global screen, screen_size
        global snake_pos, food_pos, snake_speed
    
        is_running = False
        is_paused = False
        is_dead = False
    
        repaint()
        show_msg("Press any key to start ...")
    
        # 主循环
        while True:
            # 处理游戏事件
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    game_quit()
                elif event.type == pygame.KEYDOWN:
                    if event.key == pygame.K_UP:
                        snake_speed = [0, -20]
                    elif event.key == pygame.K_DOWN:
                        snake_speed = [0, 20]
                    elif event.key == pygame.K_LEFT:
                        snake_speed = [-20, 0]
                    elif event.key == pygame.K_RIGHT:
                        snake_speed = [20, 0]
                    elif event.key == pygame.K_y:
                        if is_dead:
                            init()
                            is_dead = False
                        is_running = True
                    elif event.key == pygame.K_n:
                        if is_dead: game_quit()
                        else: is_running = True
                    elif event.key == pygame.K_ESCAPE:
                        if is_running:
                            show_msg(">>> Paused <<<")
                            is_paused = not is_paused
                    else: # 任意键进入开始状态
                        is_running = True
    
            if not is_running: continue
            if is_paused and is_running: continue
    
            # 更新蛇的位置
            snake_pos.insert(0, [snake_pos[0][0] + snake_speed[0], snake_pos[0][1] + snake_speed[1]])
    
            # 检查蛇头是否碰到食物
            if snake_pos[0] == food_pos:
                food_pos = [random.randrange(1, screen_size[0] // 20) * 20, random.randrange(1, screen_size[1] // 20) * 20]
            else:
                snake_pos.pop()
    
            # 检查蛇头是否碰到墙壁或者蛇身
            if snake_pos[0][0] < 0 or snake_pos[0][0] >= screen_size[0] or snake_pos[0][1] < 0 or snake_pos[0][1] >= screen_size[1] or snake_pos[0] in snake_pos[1:]:
                show_msg("Dead! Again? (Y or N)")
                is_running = False
                is_dead = True
                continue
    
            # 重画界面及蛇和食物
            repaint()
    
            # 控制游戏速度
            pygame.time.Clock().tick(10)
    
    if __name__ == "__main__":
    
        init()
        main()

### 改进过程二 ###

#### 增加显示得分 ####

每吃到一个食物+10分，蛇长和食物靠近边界会有额外加分；顺带显示出蛇的坐标位置。

![116ccdc7cbd94a9e8fabe3ee789c36df.png][]

函数show\_msg\_at()，比show\_msg增加x,y坐标，把信息显示到指定的位置：

def show\_msg\_at(**x, y,** msg):  
font = pygame.**font.SysFont**('Consolas', 14) \# 使用系统字库  
text = font.render(msg, True, BLACK)  
text\_rect = text.get\_rect()  
 **text\_rect.x, text\_rect.y** = **x, y**  
screen.blit(text, text\_rect)  
pygame.display.flip()

另外新增一个全局变量 scores，当碰到食物时加10分，蛇长超过5以及食物靠近边界的距离小3会有额外加分，规则可以自己定，例如：

**if snake\_pos\[0\] == food\_pos:**  
 **scores += 10 + len(snake\_pos) // 5**  
 **if not 1 < snake\_pos\[0\]\[0\]//20 < 30 or not 1 < snake\_pos\[0\]\[1\]//20 < 22:  
scores += 5**

**完整代码如下：**

import pygame
    import sys
    import random
    
    # 定义颜色
    BLACK = (0, 0, 0)
    WHITE = (255, 255, 255)
    RED   = (255, 0, 0)
    GREEN = (0, 255, 0)
    BLUE  = (0, 0, 255)
    GREY  = (220, 220, 220)  # 淡灰色
    DARK  = (120, 120, 120)  # 深灰色
    
    def init():
        global screen, screen_size, scores
        global snake_pos, food_pos, snake_speed
    
        # 初始化pygame
        scores = 0
        pygame.init()
    
        # 设置屏幕大小
        screen_size = (640, 480)
        screen = pygame.display.set_mode(screen_size)
    
        # 设置游戏标题
        pygame.display.set_caption("贪吃蛇")
    
        # 蛇的初始位置
        snake_pos = [[100, 100], [80, 100], [60, 100]]
    
        # 食物的初始位置
        food_pos = [300, 300]
    
        # 蛇的初始速度
        snake_speed = [20, 0]
    
    
    def show_msg(msg, color = BLUE):
        x = screen.get_rect().centerx
        y = screen.get_rect().centery - 50
        font = pygame.font.Font(None, 36)
        text = font.render(msg, True, color)
        text_rect = text.get_rect()
        text_rect.centerx = x
        text_rect.centery = y
        rectangle1 = pygame.Rect(x-155, y-25, 320, 60)
        rectangle2 = pygame.Rect(x-160, y-30, 320, 60)
        pygame.draw.rect(screen, DARK, rectangle1)
        pygame.draw.rect(screen, GREY, rectangle2)
        pygame.draw.rect(screen, BLACK, rectangle2, 2) # 边框宽为2
        screen.blit(text, text_rect)
        pygame.display.flip()
    
    def repaint():
        # 绘制游戏界面
        screen.fill(WHITE)
    
        # 定义线段的端点坐标
        x,y = (-1,640,640,-1)*16, []
        for i in range(36):
            for _ in range(2):
                y.append(19+i*20)
    
        # 使用pygame.draw.lines()函数绘制线段
        points = list(zip(x,y))
        pygame.draw.lines(screen, GREY, False, points, 1) # 线宽为1
        points = list(zip(y,x))
        pygame.draw.lines(screen, GREY, False, points, 1)   
    
        # 重画蛇和食物
        for pos in snake_pos:
            pygame.draw.rect(screen, GREEN, pygame.Rect(pos[0], pos[1], 20, 20))
        pygame.draw.rect(screen, RED, pygame.Rect(food_pos[0], food_pos[1], 20, 20))
        pygame.display.flip()
        show_msg_at(22, 6, f'Scores: {scores}')
        show_msg_at(410, 6, f'Snake coordinate: ({1+snake_pos[0][0]//20:2}, {1+snake_pos[0][1]//20:2})')
    
    def show_msg_at(x, y, msg):
        font = pygame.font.SysFont('Consolas', 14)
        text = font.render(msg, True, BLACK)
        text_rect = text.get_rect()
        text_rect.x, text_rect.y = x, y
        screen.blit(text, text_rect)
        pygame.display.flip()
    
    def game_quit():
        pygame.quit()
        sys.exit()
    
    def main():
        global screen, screen_size, scores
        global snake_pos, food_pos, snake_speed
    
        is_running = False
        is_paused = False
        is_dead = False
    
        repaint()
        show_msg("Press any key to start ...")
    
        # 主循环
        while True:
            # 处理游戏事件
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    game_quit()
                elif event.type == pygame.KEYDOWN:
                    if event.key == pygame.K_UP:
                        snake_speed = [0, -20]
                    elif event.key == pygame.K_DOWN:
                        snake_speed = [0, 20]
                    elif event.key == pygame.K_LEFT:
                        snake_speed = [-20, 0]
                    elif event.key == pygame.K_RIGHT:
                        snake_speed = [20, 0]
                    elif event.key == pygame.K_y:
                        if is_dead:
                            init()
                            is_dead = False
                        is_running = True
                    elif event.key == pygame.K_n:
                        if is_dead: game_quit()
                        else: is_running = True
                    elif event.key == pygame.K_SPACE:
                        if is_dead: continue
                        if is_paused: is_paused = False
                        is_running = True
                    elif event.key == pygame.K_ESCAPE:
                        if is_running:
                            show_msg(">>> Paused <<<")
                            is_paused = not is_paused
                    else: # 任意键进入开始状态
                        if is_dead: continue
                        is_running = True
    
            if not is_running: continue
            if is_paused and is_running: continue
    
            # 更新蛇的位置
            snake_pos.insert(0, [snake_pos[0][0] + snake_speed[0], snake_pos[0][1] + snake_speed[1]])
    
            # 检查蛇头是否碰到食物
            if snake_pos[0] == food_pos:
                scores += 10 + len(snake_pos) // 5
                if not 1 < snake_pos[0][0]//20 < 30 or not 1 < snake_pos[0][1]//20 < 22:
                    scores += 5 
                food_pos = [random.randrange(1, screen_size[0] // 20) * 20, random.randrange(1, screen_size[1] // 20) * 20]
            else:
                snake_pos.pop()
    
            # 检查蛇头是否碰到墙壁或者蛇身
            if snake_pos[0][0] < 0 or snake_pos[0][0] >= screen_size[0] or snake_pos[0][1] < 0 or snake_pos[0][1] >= screen_size[1] or snake_pos[0] in snake_pos[1:]:
                show_msg("Dead! Again? (Y or N)")
                is_running = False
                is_dead = True
                continue
    
            # 重画界面及蛇和食物
            repaint()
    
            # 控制游戏速度
            pygame.time.Clock().tick(10)
    
    if __name__ == "__main__":
    
        init()
        main()

### 改进过程三 ###

#### 增加背景景乐 ####

def play\_music(mp3, volume = 1, loops = -1):  
\# 初始化pygame的mixer模块  
**pygame.mixer**.init()  
\# 加载音乐文件  
**pygame.mixer.music**.load(mp3)  
\# 控制音量 volume = 0~1，1为最高音量  
**pygame.mixer.music**.set\_volume(volume)  
\# 播放音乐 loops = -1 为循环播放  
**pygame.mixer.music**.play(loops)

#### 增加提示音效 ####

def play\_sound(wav\_no):  
sound\_fn = f'sound\{wav\_no\}.wav'  
if os.path.exists(sound\_fn):  
alert\_sound = **pygame.mixer.Sound**(sound\_fn)  
alert\_sound.play()

#### 音乐切换 ####

快捷键 Ctrl+M

elif event.key == **pygame.K\_m and event.mod & pygame.KMOD\_CTRL**:  
\# Ctrl+M 切换背景音乐  
is\_mute = False  
**music\_no = 1 if music\_no == 3 else music\_no + 1**  
music\_fn = f"voice\{music\_no\}.mp3"  
if os.path.exists(music\_fn):  
t = threading.Thread(target=play\_music, args=(music\_fn,0.8,))  
t.start()

#### 静音切换 ####

快捷键 Ctrl+S

elif event.key == **pygame.K\_s and event.mod & pygame.KMOD\_CTRL**:  
\# Ctrl+S 切换静音状态  
is\_mute = not is\_mute  
if is\_mute:  
pygame.mixer.music**.pause()**  
else:  
pygame.mixer.music**.unpause()**

#### mixer.music.play 注意事项 ####

1. pygame.mixer.music.play() 只能播放pygame支持的音频格式，包括WAV, MP3等。

2. 如果音频文件未找到或无法读取，pygame.mixer.music.play( ) 会抛出一个异常。使用需要确保音频文件的路径正确，且文件存在。导入os库，用os.path.exists(music\_file) 判断文件是否存在。

3. pygame.mixer.music.play() 是一个阻塞函数，在音频播放期间程序将不会执行其他操作。如果需要在播放同时执行其他操作，需要在一个单独的线程中调用pygame.mixer.music.play()。

4. 多线程需要导入threading库，例如：

t = threading.Thread(target=play\_music, args=(music\_fn,0.8,))  
t.start()

--------------------

#### 原版帮助摘要 ####

##### pygame.mixer #####

NAME  
pygame.mixer\_music - pygame module for controlling streamed audio

FUNCTIONS  
fadeout(...)  
fadeout(time) -> None  
stop music playback after fading out  
  
get\_busy(...)  
get\_busy() -> bool  
check if the music stream is playing  
  
get\_endevent(...)  
get\_endevent() -> type  
get the event a channel sends when playback stops  
  
get\_pos(...)  
get\_pos() -> time  
get the music play time  
  
get\_volume(...)  
get\_volume() -> value  
get the music volume  
  
 **load(...)**  
load(filename) -> None  
load(fileobj, namehint=) -> None  
Load a music file for playback  
  
**pause(...)**  
pause() -> None  
temporarily stop music playback  
  
 **play(...)**  
play(loops=0, start=0.0, fade\_ms=0) -> None  
Start the playback of the music stream  
  
queue(...)  
queue(filename) -> None  
queue(fileobj, namehint=, loops=0) -> None  
queue a sound file to follow the current  
  
rewind(...)  
rewind() -> None  
restart music  
  
set\_endevent(...)  
set\_endevent() -> None  
set\_endevent(type) -> None  
have the music send an event when playback stops  
  
set\_pos(...)  
set\_pos(pos) -> None  
set position to play from  
  
**set\_volume**(...)  
set\_volume(volume) -> None  
set the music volume  
  
stop(...)  
stop() -> None  
stop the music playback  
  
unload(...)  
unload() -> None  
Unload the currently loaded music to free up resources  
  
 **unpause**(...)  
unpause() -> None  
resume paused music

--------------------

##### pygame.mixer.Sound #####

--------------------

**完整代码：**

import pygame
    import sys, os
    import random
    import threading
    
    # 定义颜色
    BLACK = (0, 0, 0)
    WHITE = (255, 255, 255)
    RED   = (255, 0, 0)
    GREEN = (0, 255, 0)
    BLUE  = (0, 0, 255)
    GREY  = (220, 220, 220)  # 淡灰色
    DARK  = (120, 120, 120)  # 深灰色
    
    def init():
        global screen, screen_size, scores
        global snake_pos, food_pos, snake_speed
    
        # 初始化pygame
        scores = 0
        pygame.init()
    
        # 设置屏幕大小
        screen_size = (640, 480)
        screen = pygame.display.set_mode(screen_size)
    
        # 设置游戏标题
        pygame.display.set_caption("贪吃蛇")
    
        # 蛇的初始位置
        snake_pos = [[100, 100], [80, 100], [60, 100]]
    
        # 食物的初始位置
        food_pos = [300, 300]
    
        # 蛇的初始速度
        snake_speed = [20, 0]
    
    def play_music(mp3, volume = 1, loops = -1):
        # 初始化pygame的mixer模块
        pygame.mixer.init()
        # 加载音乐文件
        pygame.mixer.music.load(mp3)
        # 控制音量
        pygame.mixer.music.set_volume(volume)
        # 播放音乐
        pygame.mixer.music.play(loops)
    
    def play_sound(wav_no):
        sound_fn = f'sound{wav_no}.wav'
        if os.path.exists(sound_fn):
            alert_sound = pygame.mixer.Sound(sound_fn)
            alert_sound.play()
    
    def show_msg(msg, color = BLUE):
        x = screen.get_rect().centerx
        y = screen.get_rect().centery - 50
        font = pygame.font.Font(None, 36)
        text = font.render(msg, True, color)
        text_rect = text.get_rect()
        text_rect.centerx = x
        text_rect.centery = y
        rectangle1 = pygame.Rect(x-155, y-25, 320, 60)
        rectangle2 = pygame.Rect(x-160, y-30, 320, 60)
        pygame.draw.rect(screen, DARK, rectangle1)
        pygame.draw.rect(screen, GREY, rectangle2)
        pygame.draw.rect(screen, BLACK, rectangle2, 2) # 边框宽为2
        screen.blit(text, text_rect)
        pygame.display.flip()
    
    def repaint():
        # 绘制游戏界面
        screen.fill(WHITE)
    
        # 定义线段的端点坐标
        x,y = (-1,640,640,-1)*16, []
        for i in range(36):
            for _ in range(2):
                y.append(19+i*20)
    
        # 使用pygame.draw.lines()函数绘制线段
        points = list(zip(x,y))
        pygame.draw.lines(screen, GREY, False, points, 1) # 线宽为1
        points = list(zip(y,x))
        pygame.draw.lines(screen, GREY, False, points, 1)   
    
        # 重画蛇和食物
        for pos in snake_pos:
            pygame.draw.rect(screen, GREEN, pygame.Rect(pos[0], pos[1], 20, 20))
        pygame.draw.rect(screen, RED, pygame.Rect(food_pos[0], food_pos[1], 20, 20))
        pygame.display.flip()
        show_msg_at(22, 6, f'Scores: {scores}')
        show_msg_at(410, 6, f'Snake coordinate: ({1+snake_pos[0][0]//20:2}, {1+snake_pos[0][1]//20:2})')
    
    def show_msg_at(x, y, msg):
        font = pygame.font.SysFont('Consolas', 14)
        text = font.render(msg, True, BLACK)
        text_rect = text.get_rect()
        text_rect.x, text_rect.y = x, y
        screen.blit(text, text_rect)
        pygame.display.flip()
    
    def game_quit():
        pygame.quit()
        sys.exit()
    
    def main():
        global screen, screen_size, scores
        global snake_pos, food_pos, snake_speed
    
        is_running = False
        is_paused = False
        is_dead = False
        is_mute = False
        
        repaint()
        show_msg("Press any key to start ...")
    
        # 创建一个线程来播放音乐
        music_no = 1
        music_fn = "voice1.mp3"
        if os.path.exists(music_fn):
            t = threading.Thread(target=play_music, args=(music_fn,0.8,))
            t.start()
    
        # 主循环
        while True:
            # 处理游戏事件
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    game_quit()
                elif event.type == pygame.KEYDOWN:
                    if event.key == pygame.K_UP:
                        snake_speed = [0, -20]
                    elif event.key == pygame.K_DOWN:
                        snake_speed = [0, 20]
                    elif event.key == pygame.K_LEFT:
                        snake_speed = [-20, 0]
                    elif event.key == pygame.K_RIGHT:
                        snake_speed = [20, 0]
                    elif event.key == pygame.K_y:
                        if is_dead:
                            init()
                            is_dead = False
                        is_running = True
                    elif event.key == pygame.K_n:
                        if is_dead: game_quit()
                        else: is_running = True
                    elif event.key == pygame.K_SPACE:
                        if is_dead: continue
                        if is_paused: is_paused = False
                        is_running = True
                    elif event.key == pygame.K_ESCAPE:
                        if is_running:
                            show_msg(">>> Paused <<<")
                            is_paused = not is_paused
                            if not is_mute and is_paused: play_sound(1)
                    elif event.key == pygame.K_m and event.mod & pygame.KMOD_CTRL:
                        # Ctrl+M 切换背景音乐
                        is_mute = False
                        music_no = 1 if music_no == 3 else music_no + 1
                        music_fn = f"voice{music_no}.mp3"
                        if os.path.exists(music_fn):
                            t = threading.Thread(target=play_music, args=(music_fn,0.8,))
                            t.start()
                    elif event.key == pygame.K_s and event.mod & pygame.KMOD_CTRL:
                        # Ctrl+S 切换静音状态
                        is_mute = not is_mute
                        if is_mute:
                            pygame.mixer.music.pause()
                        else:
                            pygame.mixer.music.unpause()
                        is_running = True
                    else: # 任意键进入开始状态
                        if is_dead: continue
                        is_running = True
    
            if not is_running: continue
            if is_paused and is_running: continue
    
            # 更新蛇的位置
            snake_pos.insert(0, [snake_pos[0][0] + snake_speed[0], snake_pos[0][1] + snake_speed[1]])
    
            # 检查蛇头是否碰到食物
            if snake_pos[0] == food_pos:
                scores += 10 + len(snake_pos) // 5
                if not 1 < snake_pos[0][0]//20 < 30 or not 1 < snake_pos[0][1]//20 < 22:
                    scores += 5
                if not is_mute: play_sound(2)
                food_pos = [random.randrange(1, screen_size[0] // 20) * 20, random.randrange(1, screen_size[1] // 20) * 20]
            else:
                snake_pos.pop()
    
            # 检查蛇头是否碰到墙壁或者蛇身
            if snake_pos[0][0] < 0 or snake_pos[0][0] >= screen_size[0] or snake_pos[0][1] < 0 or snake_pos[0][1] >= screen_size[1] or snake_pos[0] in snake_pos[1:]:
                show_msg("Dead! Again? (Y or N)")
                is_running = False
                is_dead = True
                if not is_mute: play_sound(3)
                continue
    
            # 重画界面及蛇和食物
            repaint()
    
            # 控制游戏速度
            pygame.time.Clock().tick(10)
    
    if __name__ == "__main__":
    
        init()
        main()

### 改进过程四 ###

#### 增加WASD方向键 ####

DOS时代的游戏经常用W、A、S、D四个字母，对应上左下右四个方向键，上面的代码中，快捷键 ctrl+S 换成 strl+Q 避免冲突。

另外，游戏中按了与前进方向相反的键，相当于蛇的自杀行为。为了避免这个bug，引入一个表示蛇移动方向的变量direction：

if not is\_paused:  
if (event.key == pygame.K\_w or event.key == pygame.K\_UP) and direction != DOWN:  
direction = UP  
elif (event.key == pygame.K\_s or event.key == pygame.K\_DOWN) and direction != UP:  
direction = DOWN  
elif (event.key == pygame.K\_a or event.key == pygame.K\_LEFT) and direction != RIGHT:  
direction = LEFT  
elif (event.key == pygame.K\_f or event.key == pygame.K\_RIGHT) and direction != LEFT:  
direction = RIGHT

把移动和按键分离，控制移动的代码放到后面去：

if direction == UP:  
snake\_speed = \[0, -20\]  
elif direction == DOWN:  
snake\_speed = \[0, 20\]  
elif direction == LEFT:  
snake\_speed = \[-20, 0\]  
elif direction == RIGHT:  
snake\_speed = \[20, 0\]

#### 增加退出事件的确认 ####

pygame 没有弹窗一类的方法，导入tkinter库，由messagebox来实现：

from tkinter import messagebox  
......  
for event in pygame.event.get():  
if event.type == pygame.QUIT:  
if messagebox.askyesno("确认", "是否要退出？"):  
game\_quit()  
......

效果如下：

![d260beb31b1e49178521982c472b9d4c.png][]

最后，增加了按暂停键时背景音乐也暂停的功能；另外修改了一些小错误，估计还会有bug出现，状态变量设置多了感觉逻辑有点乱。

--------------------

## 小结 ##

本文以贪吃蛇游戏为例，对pygame编程的一个简单框架进行了深入的学习，包括对画图、字体、音乐等各个方面操作的各种方法和函数，学习后在pygame这方面的编程能力有所长进提高。

### pygame编程框架 ###

import pygame
    import sys
    
    # 初始化Pygame
    pygame.init()
    
    # 设置窗口大小
    screen_size = (800, 600)
    
    # 创建窗口
    screen = pygame.display.set_mode(screen_size)
    
    # 设置窗口标题
    pygame.display.set_caption("Pygame Example")
    
    # 主循环
    while True:
        # 处理事件
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                pygame.quit()
                sys.exit()
            elif event.type == ...
                ... // 处理按键事件
    
        # 填充背景色
        screen.fill((255, 255, 255))
    
        # 绘制矩形
        pygame.draw.rect(screen, (0, 0, 255), (400, 300, 100, 50))
    
        # 更新显示
        pygame.display.flip()

### 完整代码 ###

import pygame
    from sys import exit as system
    from random  import randrange
    from os.path import exists
    from tkinter import messagebox
    from threading import Thread
    
    # 定义颜色
    BLACK = (0, 0, 0)
    WHITE = (255, 255, 255)
    RED   = (255, 0, 0)
    GREEN = (0, 255, 0)
    BLUE  = (0, 0, 255)
    GREY  = (220, 220, 220)  # 淡灰色
    DARK  = (120, 120, 120)  # 深灰色
    
    def init():
        global screen, screen_size, scores
        global snake_pos, food_pos, snake_speed
    
        # 初始化pygame
        scores = 0
        pygame.init()
    
        # 设置屏幕大小
        screen_size = (640, 480)
        screen = pygame.display.set_mode(screen_size)
    
        # 设置游戏标题
        pygame.display.set_caption("贪吃蛇")
    
        # 蛇的初始位置
        snake_pos = [[100, 100], [80, 100], [60, 100]]
    
        # 食物的初始位置
        food_pos = [300, 300]
    
        # 蛇的初始速度
        snake_speed = [20, 0]
    
    def play_music(mp3, volume = 1, loops = -1):
        # 初始化pygame的mixer模块
        pygame.mixer.init()
        # 加载音乐文件
        pygame.mixer.music.load(mp3)
        # 控制音量
        pygame.mixer.music.set_volume(volume)
        # 播放音乐
        pygame.mixer.music.play(loops)
    
    def play_sound(wav_no):
        sound_fn = f'sound{wav_no}.wav'
        if exists(sound_fn):
            alert_sound = pygame.mixer.Sound(sound_fn)
            alert_sound.play()
    
    def show_msg(msg, color = BLUE):
        x = screen.get_rect().centerx
        y = screen.get_rect().centery - 50
        font = pygame.font.Font(None, 36)
        text = font.render(msg, True, color)
        text_rect = text.get_rect()
        text_rect.centerx = x
        text_rect.centery = y
        rectangle1 = pygame.Rect(x-155, y-25, 320, 60)
        rectangle2 = pygame.Rect(x-160, y-30, 320, 60)
        pygame.draw.rect(screen, DARK, rectangle1)
        pygame.draw.rect(screen, GREY, rectangle2)
        pygame.draw.rect(screen, BLACK, rectangle2, 2) # 边框宽为2
        screen.blit(text, text_rect)
        pygame.display.flip()
    
    def repaint():
        # 绘制游戏界面
        screen.fill(WHITE)
    
        # 定义线段的端点坐标
        x,y = (-1,640,640,-1)*16, []
        for i in range(36):
            for _ in range(2):
                y.append(19+i*20)
    
        # 使用pygame.draw.lines()函数绘制线段
        points = list(zip(x,y))
        pygame.draw.lines(screen, GREY, False, points, 1) # 线宽为1
        points = list(zip(y,x))
        pygame.draw.lines(screen, GREY, False, points, 1)   
    
        # 重画蛇和食物
        for pos in snake_pos:
            pygame.draw.rect(screen, GREEN, pygame.Rect(pos[0], pos[1], 20, 20))
        pygame.draw.rect(screen, RED, pygame.Rect(food_pos[0], food_pos[1], 20, 20))
        pygame.display.flip()
        show_msg_at(22, 6, f'Scores: {scores}')
        show_msg_at(410, 6, f'Snake coordinate: ({1+snake_pos[0][0]//20:2}, {1+snake_pos[0][1]//20:2})')
    
    def show_msg_at(x, y, msg):
        font = pygame.font.SysFont('Consolas', 14)
        text = font.render(msg, True, BLACK)
        text_rect = text.get_rect()
        text_rect.x, text_rect.y = x, y
        screen.blit(text, text_rect)
        pygame.display.flip()
    
    def game_quit():
        pygame.quit()
        system()
    
    def main():
        global screen, screen_size, scores
        global snake_pos, food_pos, snake_speed
    
        is_running = False
        is_paused = False
        is_dead = False
        is_mute = False
        
        repaint()
        show_msg("Press any key to start ...")
    
        # 创建一个线程来播放音乐
        music_no = 1
        music_fn = "voice1.mp3"
        if exists(music_fn):
            t = Thread(target=play_music, args=(music_fn,0.8,))
            t.start()
    
        # 主循环
        UP, DOWN, LEFT, RIGHT = 1, 2, 3, 4
        direction = RIGHT
        while True:
            # 处理游戏事件
            for event in pygame.event.get():
                if event.type == pygame.QUIT:
                    if messagebox.askyesno("确认", "是否要退出？"):
                        game_quit()
                elif event.type == pygame.KEYDOWN:
                    # 增加 WASD 四键对应 上左下右 方向键
                    if not is_paused:
                        if   (event.key == pygame.K_w or event.key == pygame.K_UP)    and direction != DOWN:
                            direction = UP
                        elif (event.key == pygame.K_s or event.key == pygame.K_DOWN)  and direction != UP:
                            direction = DOWN
                        elif (event.key == pygame.K_a or event.key == pygame.K_LEFT)  and direction != RIGHT:
                            direction = LEFT
                        elif (event.key == pygame.K_f or event.key == pygame.K_RIGHT) and direction != LEFT:
                            direction = RIGHT
                    if event.key == pygame.K_y:
                        if is_dead:
                            init()
                            is_dead = False
                        is_running = True
                    elif event.key == pygame.K_n:
                        if is_dead: game_quit()
                        else: is_running = True
                    elif event.key == pygame.K_SPACE:
                        if is_dead: continue
                        if is_paused:
                            is_paused = False
                            pygame.mixer.music.unpause()
                        is_running = True
                    elif event.key == pygame.K_ESCAPE:
                        if is_running:
                            show_msg(">>> Paused <<<")
                            is_paused = not is_paused
                            if is_paused:
                                pygame.mixer.music.pause()
                                if not is_mute: play_sound(1)
                            else:
                                pygame.mixer.music.unpause()
                    elif event.key == pygame.K_m and event.mod & pygame.KMOD_CTRL:
                        # Ctrl+M 切换背景音乐
                        is_mute = False
                        music_no = 1 if music_no == 3 else music_no + 1
                        music_fn = f"voice{music_no}.mp3"
                        if exists(music_fn):
                            t = Thread(target=play_music, args=(music_fn,0.8,))
                            t.start()
                    elif event.key == pygame.K_q and event.mod & pygame.KMOD_CTRL:
                        # Ctrl+Q 切换静音状态
                        is_mute = not is_mute
                        if is_mute:
                            pygame.mixer.music.pause()
                        else:
                            pygame.mixer.music.unpause()
                        is_running = True
                    else: # 任意键进入开始状态
                        if is_dead: continue
                        is_running = True
    
            if not is_running: continue
            if is_paused: continue
    
            if direction   == UP:
                snake_speed = [0, -20]
            elif direction == DOWN:
                snake_speed = [0, 20]
            elif direction == LEFT:
                snake_speed = [-20, 0]
            elif direction == RIGHT:
                snake_speed = [20, 0]
    
            # 更新蛇的位置
            snake_pos.insert(0, [snake_pos[0][0] + snake_speed[0], snake_pos[0][1] + snake_speed[1]])
    
            # 检查蛇头是否碰到食物
            if snake_pos[0] == food_pos:
                scores += 10 + len(snake_pos) // 5
                if not 1 < snake_pos[0][0]//20 < 30 or not 1 < snake_pos[0][1]//20 < 22:
                    scores += 5
                if not is_mute: play_sound(2)
                food_pos = [randrange(1, screen_size[0] // 20) * 20, randrange(1, screen_size[1] // 20) * 20]
            else:
                snake_pos.pop()
    
            # 检查蛇头是否碰到墙壁或者蛇身
            if snake_pos[0][0] < 0 or snake_pos[0][0] >= screen_size[0] or snake_pos[0][1] < 0 or snake_pos[0][1] >= screen_size[1] or snake_pos[0] in snake_pos[1:]:
                show_msg("Dead! Again? (Y or N)")
                is_running = False
                is_dead = True
                direction = RIGHT
                if not is_mute: play_sound(3)
                continue
    
            # 重画界面及蛇和食物
            repaint()
    
            # 控制游戏速度
            pygame.time.Clock().tick(10)
    
    if __name__ == "__main__":
    
        init()
        main()

最终版的源代码及音乐文件列表如下：

![a11fde1e884941a28802693ea9655fa8.png][]

下载地址：

[https://download.csdn.net/download/boysoft2002/88231961][https_download.csdn.net_download_boysoft2002_88231961]

[1ae28d15992f405bb7fd51daa60c3dc2.gif]: https://img-blog.csdnimg.cn/1ae28d15992f405bb7fd51daa60c3dc2.gif
[Link 1]: https://hannyang.blog.csdn.net/article/details/132343605
[430570d634af43d699af3c431b6ec93f.png]: https://img-blog.csdnimg.cn/430570d634af43d699af3c431b6ec93f.png
[f38182e16948453488d737293b8d5fc4.png]: https://img-blog.csdnimg.cn/f38182e16948453488d737293b8d5fc4.png
[3768406c79d048bd9914ae50ed9c4ab9.png]: https://img-blog.csdnimg.cn/3768406c79d048bd9914ae50ed9c4ab9.png
[116ccdc7cbd94a9e8fabe3ee789c36df.png]: https://img-blog.csdnimg.cn/116ccdc7cbd94a9e8fabe3ee789c36df.png
[d260beb31b1e49178521982c472b9d4c.png]: https://img-blog.csdnimg.cn/d260beb31b1e49178521982c472b9d4c.png
[a11fde1e884941a28802693ea9655fa8.png]: https://img-blog.csdnimg.cn/a11fde1e884941a28802693ea9655fa8.png
[https_download.csdn.net_download_boysoft2002_88231961]: https://download.csdn.net/download/boysoft2002/88231961