基于python的贪吃蛇

最近刚接触python ，感觉很有意思，发现python非常灵活，应用比较广泛，通过加载模块，可以完成很多功能。看了一篇关于基于贪吃蛇的python的实现方法，将其中的思路进行总结。

程序流程分为三个部分：1、开始界面 2、运行游戏 3、退出游戏 。主要完成界面背景的设置，然后等待按键开始游戏，贪吃蛇采用列表存储，重点是通过判断head的坐标，如果与苹果的坐标重合，就吃掉苹果，如果不在界面坐标轴范围，表示撞墙，游戏结束

#-*- coding:utf-8 -*-

import pygame, sys, random

from pygame.locals import*

FPS = 15

WINDOWWIDTH =640

WINDOWHEIGHT = 480

CELLSIZE = 20

assert WINDOWWIDTH % CELLSIZE == 0, "Window width must be a multiple of cell size"

assert WINDOWHEIGHT % CELLSIZE == 0, "Window height muset be multiple of cell size"

CELLWIDTH = WINDOWWIDTH / CELLSIZE #屏幕上在X坐标轴上显示的方格数

CELLHEIGHT = WINDOWHEIGHT / CELLSIZE #屏幕上在Y坐标轴上显示的方格数

#RGB

WHITE = (255, 255, 255)

BLACK = (0, 0 , 0)

RED = (255, 0, 0)

GREEN = (0, 255, 0)

DARKGREEN = (0, 155, 0)

DARKGRAY = (40, 40, 40)

BGCOLOR = BLACK

UP = 'up'

DOWN = 'down'

LEFT = 'left'

RIGHT = 'right'

HEAD = 0 #很巧妙的运用

#main function

def main():

global FPSCLOCK, DISPLAYSURF, BASICFONT

pygame.init()

FPSCLOCK = pygame.time.Clock()

DISPLAYSURF = pygame.display.set_mode((WINDOWWIDTH, WINDOWHEIGHT))

BASICFONT = pygame.font.Font('freesansbold.ttf', 18)

pygame.display.set_caption('Wormy')

showStartScreen() #显示起始画面

while True:

runGame() #运行游戏主体

showGameOverScreen() #显示游戏结束画面

def runGame():

#设置蛇身开始在随机位置

startx = random.randint(5, CELLWIDTH-6)

starty = random.randint(5, CELLHEIGHT-6)

wormCoods = [{'x': startx, 'y': starty},

{'x': startx-1, 'y': starty},

{'x': startx-2, 'y': starty}]

direction = RIGHT #蛇初始方向向右

#得到一个随机苹果的位置

apple = getRandomLocation()

while True:

for event in pygame.event.get():

if event.type == QUIT:

terminate()

elif event.type == KEYDOWN: #处理蛇的移动方向

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()

#看蛇身是否撞击到自己或四周墙壁

if wormCoods[HEAD]['x'] == -1 or wormCoods[HEAD]['x'] == CELLWIDTH or wormCoods[HEAD]['y'] == -1 or wormCoods[HEAD]['y'] == CELLHEIGHT:

return #game over

for wormBody in wormCoods[1:]:

if wormBody['x'] == wormCoods[HEAD]['x'] and wormBody['y'] == wormCoods[HEAD]['y']:

return #game over

#判断蛇是否吃到苹果

if wormCoods[HEAD]['x'] == apple['x'] and wormCoods[HEAD]['y'] == apple['y']:

apple = getRandomLocation() #随机显示一个新的苹果

else:

del wormCoods[-1] #删除蛇的尾巴，即列表最后一个小方块

#根据蛇的移动方向，给蛇添加一个新的头部

if direction == UP:

newHead = {'x': wormCoods[HEAD]['x'], 'y': wormCoods[HEAD]['y']-1}

elif direction == DOWN:

newHead = {'x': wormCoods[HEAD]['x'], 'y': wormCoods[HEAD]['y']+1}

elif direction == LEFT:

newHead = {'x': wormCoods[HEAD]['x']-1, 'y': wormCoods[HEAD]['y']}

elif direction == RIGHT:

newHead = {'x': wormCoods[HEAD]['x']+1, 'y': wormCoods[HEAD]['y']}

wormCoods.insert(0,newHead)

DISPLAYSURF.fill(BGCOLOR)

drawGrid() #画屏幕上的小方格

drawWorm(wormCoods) #画蛇身

drawApple(apple) #画苹果

drawScore(len(wormCoods) - 3)#显示蛇身长度计算玩家的分数

pygame.display.update()

FPSCLOCK.tick(FPS)

#提示按键消息

def drawPressKeyMsg():

pressKeySurf = BASICFONT.render('Press a key to play.', True, DARKGRAY)

pressKeyRect = pressKeySurf.get_rect()

pressKeyRect.topleft = (WINDOWWIDTH - 200, WINDOWHEIGHT-30)

DISPLAYSURF.blit(pressKeySurf, pressKeyRect)

#检测按键游戏是否要退出

def checkForKeyPress():

if len(pygame.event.get(QUIT)) > 0:

terminate()

keyUpEvents = pygame.event.get(KEYUP)

if len(keyUpEvents) == 0:

return None

if keyUpEvents[0].key == K_ESCAPE:

terminate()

return keyUpEvents[0].key

#显示开始界面

def showStartScreen():

titleFont = pygame.font.Font('freesansbold.ttf', 100)

titleSurf1 = titleFont.render('Hello!', True, WHITE, DARKGREEN)

titleSurf2 = titleFont.render('Wormy!', True, GREEN)

degrees1 = 0

degrees2 = 0

while True:

DISPLAYSURF.fill(BGCOLOR)

rotatedSurf1 = pygame.transform.rotate(titleSurf1, degrees1)

rotatedRect1 = rotatedSurf1.get_rect()

rotatedRect1.center = (WINDOWWIDTH / 2, WINDOWHEIGHT / 2)

DISPLAYSURF.blit(rotatedSurf1,rotatedRect1)

rotatedSurf2 = pygame.transform.rotate(titleSurf2, degrees2)

rotatedRect2 = rotatedSurf2.get_rect()

rotatedRect2.center = (WINDOWWIDTH / 2, WINDOWHEIGHT / 2)

DISPLAYSURF.blit(rotatedSurf2,rotatedRect2)

drawPressKeyMsg()

if checkForKeyPress():

pygame.event.get()

return

pygame.display.update()

FPSCLOCK.tick(FPS)

degrees1 += 3

degrees2 += 7

#游戏退出

def terminate():

pygame.quit()

sys.exit()

#随机显示苹果的位置

def getRandomLocation():

return {'x': random.randint(0, CELLWIDTH - 1), 'y': random.randint(0, CELLHEIGHT - 1)}

#游戏结束时的画面

def showGameOverScreen():

gameOverFont = pygame.font.Font('freesansbold.ttf', 150)

gameSurf = gameOverFont.render('GAME', True, WHITE)

overSurf = gameOverFont.render('OVER', True, WHITE)

gameRect = gameSurf.get_rect()

overRect = overSurf.get_rect()

gameRect.midtop = (WINDOWWIDTH / 2, 10)

overRect.midtop = (WINDOWWIDTH / 2, gameRect.height + 10 + 25)

DISPLAYSURF.blit(gameSurf, gameRect)

DISPLAYSURF.blit(overSurf, overRect)

drawPressKeyMsg()

pygame.display.update()

pygame.time.wait(500)

checkForKeyPress()

while True:

if checkForKeyPress():

pygame.event.get()

return

def drawScore(score):

scoreSurf = BASICFONT.render('Score: %s' %(score), True, WHITE)

scoreRect = scoreSurf.get_rect()

scoreRect.topleft = (WINDOWWIDTH - 120, 10)

DISPLAYSURF.blit(scoreSurf, scoreRect)

def drawWorm(wormCoods):

for coord in wormCoods:

x = coord['x'] * CELLSIZE

y = coord['y'] * CELLSIZE

wormSegmentRect = pygame.Rect(x, y, CELLSIZE, CELLSIZE)

pygame.draw.rect(DISPLAYSURF, DARKGREEN, wormSegmentRect)

wormInnerSegmentRect = pygame.Rect(x+4, y+4, CELLSIZE-8, CELLSIZE-8)

pygame.draw.rect(DISPLAYSURF, GREEN, wormInnerSegmentRect)

def drawApple(coord):

x = coord['x'] * CELLSIZE

y = coord['y'] * CELLSIZE

appleRect = pygame.Rect(x, y, CELLSIZE, CELLSIZE)

pygame.draw.rect(DISPLAYSURF, RED, appleRect)

def drawGrid():

for x in range(0, WINDOWWIDTH, CELLSIZE):

pygame.draw.line(DISPLAYSURF, DARKGRAY, (x, 0), (x, WINDOWHEIGHT))

for y in range(0, WINDOWHEIGHT, CELLSIZE):

pygame.draw.line(DISPLAYSURF, DARKGRAY, (0, y), (WINDOWWIDTH, y))

if __name__ == '__main__':

main()