python实现简单的贪吃蛇游戏

import sys
import pygame
import random

class Button(object):#定义按钮类
 def __init__(self,begin1,begin2,restart1,restart2,position,position2):
 self.gamebegin1=pygame.image.load(begin1).convert_alpha()#导入开始和重启按钮图片
 self.gamebegin2=pygame.image.load(begin2).convert_alpha()
 self.gamerestart1=pygame.image.load(restart1).convert_alpha()
 self.gamerestart2=pygame.image.load(restart2).convert_alpha()
 self.position=position
 self.position2=position2
 
 def ifpress(self):
 point_x,point_y=pygame.mouse.get_pos()#找到鼠标光标所在位置
 x,y=self.position#指定的点击按钮位置
 w,h=self.gamebegin1.get_size()#定义按钮尺寸
 x-=w/2
 y-=h/2
 if_x=x-w/2<point_x<x+w/2#判断鼠标光标是否在按钮上
 if_y=y-h/2<point_y<y+h/2
 return if_x and if_y

 def ispress(self):
 x,y=self.position
 w,h=self.gamebegin1.get_size()
 x-=w/2
 y-=h/2
 if self.ifpress():#如果鼠标光标在按钮上，图片显示为gamebegin1，否则显示为gamebegin2
  screen.blit(self.gamebegin1,(x-w/2+8,y-h/2+7))  
 else:
  screen.blit(self.gamebegin2,(x-w/2,y-h/2))
 #定义重启按钮，方法同上
 def ifrepress(self):
 point_x,point_y=pygame.mouse.get_pos()
 x,y=self.position2
 w,h=self.gamerestart1.get_size()
 x-=w/2
 y-=h/2
 if_x=x-w/2<point_x<x+w/2
 if_y=y-h/2<point_y<y+h/2
 return if_x and if_y

 def isrepress(self):
 x,y=self.position2
 w,h=self.gamerestart1.get_size()
 x-=w/2
 y-=h/2
 if self.ifrepress():
  screen.blit(self.gamerestart1,(x-w/2,y-h/2))  
 else:
  screen.blit(self.gamerestart2,(x-w/2,y-h/2))
  
def choice():#定义选择难度
 screen.fill((0,0,0))#初始界面颜色设置为黑色
 Rect1=pygame.Rect(300,300,200,100)#设置按钮尺寸
 Rect2=pygame.Rect(300,450,200,100)
 pygame.draw.rect(screen,(136,189,186),Rect1)#创建按钮
 screen.blit(font.render('grade one:',-1,(255,255,255)),(300,300))
 pygame.draw.rect(screen,(136,189,186),Rect2)
 screen.blit(font.render('grade two:',-1,(255,255,255)),(300,450))
 pygame.display.flip()#显示到屏幕上
 point_x,point_y=pygame.mouse.get_pos()#找到鼠标光标所在位置
 global a,b#定义全局变量
 if 300<point_x<500 and 300<point_y<400:#判断光标是否在按钮上
 if pygame.mouse.get_pressed()[0]:#判断鼠标是否按下
  a=8#a表示没秒执行8次
  b=1#b表示设定的一个数，与后面判断执行时有关
 if 300<point_x<500 and 450<point_y<550:
 if pygame.mouse.get_pressed()[0]:
  a=12
  b=1
 pygame.display.update()#更新屏幕
 

def getResult():#游戏结束时出现得分结果和gameover
 final_text1='Game_Over'
 final_text2='Your final score is: '+str(score)
 ft1_font=pygame.font.SysFont('Arial',70)
 ft1_surf=font.render(final_text1,1,(242,3,36))
 screen.blit(ft1_surf,[screen.get_width()/2-ft1_surf.get_width()/2,100])
 pygame.display.flip()

def main():
 pygame.init()#初始化pygame
 clock=pygame.time.Clock()#定义时间
 pygame.font.init()#初始化字符
 #需要在其它定义中出现的参数，这里还需要定义全局变量一下
 global score,screen,font,button,status,x,y,direction,snackhead,snackbody,foodposition,state,a,b
 screen=pygame.display.set_mode((640,640))#设置屏幕尺寸
 screen.fill((0,0,0))#填充屏幕颜色
 #指明图片路径
 beginname1='D://picture//gamebegin1.png'
 beginname2='D://picture//gamebegin2.png'
 restartname1='D://picture//restart1.png'
 restartname2='D://picture//restart2.png'
 pygame.display.set_caption('sanckgame')
 font=pygame.font.SysFont('Arial',40)#定义字符种类和大小
 snackhead=[120,120]#定义初始蛇的头部位置
 foodposition=[360,360]#定义初始食物位置
 snackbody=[[120,120],[100,120],[80,120]]#定义蛇全身位置 
 score=0
 x=300
 y=300
 state=0
 a=1
 b=0
 food_eat=1#食物被吃为0，否则为1
 direction='right'#定义初始运动方向
 re_direction=direction#re_direction为变化后的方向
 button = Button(beginname1,beginname2,restartname1,restartname2,(330,300),(600,320))#定义按钮数值 
 pygame.display.update()

 
 while True:
  
 for event in pygame.event.get():#遍历可能出现的事件

  if event.type == pygame.QUIT:#点击关闭，程序关闭
  pygame.quit()
  sys.exit()
 button.ispress()#显示按钮
 pygame.display.update()
 if button.ifpress():
  if pygame.mouse.get_pressed()[0]:   
  break #点击按钮，结束这里的循环，进入游戏选择难度界面
 while True:
 for event in pygame.event.get():

  if event.type == pygame.QUIT:
  pygame.quit()
  sys.exit()
 choice()#运行choice()
 if b==1:#如果点击了按钮，结束循环，进入游戏运行界面
  break
 pygame.mixer.init()#初始化音乐
 pygame.mixer.music.load('D://music//Above Everything - Capo Productions.ogg')#导入音乐 
 pygame.display.update()
 status=True
 screen=pygame.display.set_mode((640,640))
 screen.fill((0,0,0))
 while status:
 clock.tick(a)#运行速度
 
 for event in pygame.event.get():

  if event.type == pygame.QUIT:
  pygame.quit()
  sys.exit()
  
  elif event.type == pygame.KEYDOWN:#判断键盘事件
  if event.key == pygame.K_RIGHT or event.key == ord('d'):
   re_direction='right'
  if event.key == pygame.K_LEFT or event.key == ord('a'):
   re_direction='left'
  if event.key == pygame.K_UP or event.key == ord('w'):
   re_direction='up'
  if event.key == pygame.K_DOWN or event.key == ord('s'):
   re_direction='down'
 #跳出判断事件循环
 if re_direction=='right'and not direction =='left':
  direction=re_direction
 if re_direction=='left'and not direction =='right':
  direction=re_direction
 if re_direction=='up'and not direction =='down':
  direction=re_direction
 if re_direction=='down'and not direction =='up':
  direction=re_direction
 #头部坐标变化 
 if direction=='left':
  snackhead[0]-=20
 if direction=='right':
  snackhead[0]+=20
 if direction=='down':
  snackhead[1]+=20  
 if direction=='up':
  snackhead[1]-=20
 snackbody.insert(0,list(snackhead))#每移动一次，把头部新位置插入到最前面，形成新的头部
 
 if snackhead[0]==foodposition[0] and snackhead[1]==foodposition[1]:#判断蛇是否吃到了食物
  food_eat=0
  score+=1
  pygame.display.update()
 else:
  snackbody.pop()#没吃到则将位置变化前的尾部剔除出去，设的长度不变
 pygame.display.update()
 if food_eat==0:#迟到食物后生成新的食物
  x=random.randint(1,31)
  y=random.randint(1,31)
  for position in snackbody:#判断食物是否出现在蛇的身体处，出现则重新生成
  if not x == position[0] and not y == position[1]:
   state=1
  else:
   state=0
  if state ==1:
  foodposition=[int(x*20),int(y*20)]
  food_eat=1
  
 screen.fill((0,0,0))
 for position in snackbody:#画出蛇的身体和食物
  rect2=pygame.Rect(position[0],position[1],20,20)
  pygame.draw.rect(screen,(166,188,199),rect2)
  rect1=pygame.Rect(foodposition[0],foodposition[1],20,20)
  pygame.draw.rect(screen,(169,111,102),rect1)
 screen.blit(font.render('Score:'+str(score),-1,(255,255,255)),(100,50))#显示出得分
 pygame.display.update()
 #如果蛇撞到墙或自己的身体，则游戏结束
 if snackhead[0]<0 or snackhead[0]>620:
  restart()
 if snackhead[1]<0 or snackhead[1]>620:
  restart()
 for body in snackbody[1:]:
  if body[0]==snackhead[0]and body[1]==snackhead[1]:
  restart() 
 
 pygame.display.flip()
 pygame.display.update()
 if pygame.mixer.music.get_busy()==False:
  pygame.mixer.music.set_volume(0.3)
  pygame.mixer.music.play(-1)#音乐循环
 
def restart():#重新开始按钮
  
 getResult()#显示结果
 while True:
 for event in pygame.event.get():

  if event.type == pygame.QUIT:
  pygame.quit()
  sys.exit()
  
  button.isrepress()
  pygame.display.update()
  if button.ifrepress():
  pygame.display.update()
  if pygame.mouse.get_pressed()[0]:
   main()

main()