# Pygame 中的贪食蛇 AI > 原文： [https://pythonspot.com/snake-ai-in-pygame/](https://pythonspot.com/snake-ai-in-pygame/) 在本文中，我们将向您展示如何创建基本的游戏 AI（人工智能）。 本文将介绍游戏蛇的 AI。 在此游戏（蛇）中，计算机和您都在玩蛇，而计算机蛇会尝试抓住您。 简而言之：对手 AI 会根据您在棋盘上的位置尝试确定并前往目的地。 ## 添加计算机玩家： 我们使用名为 Computer 的新类扩展了代码，它将成为我们的计算机玩家。 这包含绘制和移动计算机蛇的例程。 ```py class Computer: x = [0] y = [0] step = 44 direction = 0 length = 3 updateCountMax = 2 updateCount = 0 def __init__(self, length): self.length = length for i in range(0,2000): self.x.append(-100) self.y.append(-100) # initial positions, no collision. self.x[0] = 1*44 self.y[0] = 4*44 def update(self): self.updateCount = self.updateCount + 1 if self.updateCount > self.updateCountMax: # update previous positions for i in range(self.length-1,0,-1): self.x[i] = self.x[i-1] self.y[i] = self.y[i-1] # update position of head of snake if self.direction == 0: self.x[0] = self.x[0] + self.step if self.direction == 1: self.x[0] = self.x[0] - self.step if self.direction == 2: self.y[0] = self.y[0] - self.step if self.direction == 3: self.y[0] = self.y[0] + self.step self.updateCount = 0 def moveRight(self): self.direction = 0 def moveLeft(self): self.direction = 1 def moveUp(self): self.direction = 2 def moveDown(self): self.direction = 3 def draw(self, surface, image): for i in range(0,self.length): surface.blit(image,(self.x[i],self.y[i])) ``` 然后，我们调用计算机的更新和绘制方法。 ```py def on_loop(self): self.player.update() self.computer.update() .... def on_render(self): self._display_surf.fill((0,0,0)) self.player.draw(self._display_surf, self._image_surf) self.apple.draw(self._display_surf, self._apple_surf) self.computer.draw(self._display_surf, self._image_surf) pygame.display.flip() ``` 这将使计算机蛇移动并在屏幕上绘制。 它具有与人类玩家相同的属性。 ## 为计算机玩家添加智能 因为这是一个简单的游戏，所以我们无需在游戏内部创建完整的思维机。 我们只需要计算机玩家展示一些基本情报即可。 游戏中的智能通常非常有限，因为在大多数情况下，不需要复杂性或根本没有时间实现聪明的算法。 我们将添加的算法将仅到达目的地。 它将忽略任何障碍（人类玩家）。 ```py def target(self,dx,dy): if self.x[0] > dx: self.moveLeft() if self.x[0] < dx: self.moveRight() if self.x[0] == dx: if self.y[0] < dy: self.moveDown() if self.y[0] > dy: self.moveUp() ``` ## 完整代码 我们得到以下完整代码： ```py from pygame.locals import * from random import randint import pygame import time class Apple: x = 0 y = 0 step = 44 def __init__(self,x,y): self.x = x * self.step self.y = y * self.step def draw(self, surface, image): surface.blit(image,(self.x, self.y)) class Player: x = [0] y = [0] step = 44 direction = 0 length = 3 updateCountMax = 2 updateCount = 0 def __init__(self, length): self.length = length for i in range(0,2000): self.x.append(-100) self.y.append(-100) # initial positions, no collision. self.x[0] = 1*44 self.x[0] = 2*44 def update(self): self.updateCount = self.updateCount + 1 if self.updateCount > self.updateCountMax: # update previous positions for i in range(self.length-1,0,-1): self.x[i] = self.x[i-1] self.y[i] = self.y[i-1] # update position of head of snake if self.direction == 0: self.x[0] = self.x[0] + self.step if self.direction == 1: self.x[0] = self.x[0] - self.step if self.direction == 2: self.y[0] = self.y[0] - self.step if self.direction == 3: self.y[0] = self.y[0] + self.step self.updateCount = 0 def moveRight(self): self.direction = 0 def moveLeft(self): self.direction = 1 def moveUp(self): self.direction = 2 def moveDown(self): self.direction = 3 def draw(self, surface, image): for i in range(0,self.length): surface.blit(image,(self.x[i],self.y[i])) class Computer: x = [0] y = [0] step = 44 direction = 0 length = 3 updateCountMax = 2 updateCount = 0 def __init__(self, length): self.length = length for i in range(0,2000): self.x.append(-100) self.y.append(-100) # initial positions, no collision. self.x[0] = 1*44 self.y[0] = 4*44 def update(self): self.updateCount = self.updateCount + 1 if self.updateCount > self.updateCountMax: # update previous positions for i in range(self.length-1,0,-1): self.x[i] = self.x[i-1] self.y[i] = self.y[i-1] # update position of head of snake if self.direction == 0: self.x[0] = self.x[0] + self.step if self.direction == 1: self.x[0] = self.x[0] - self.step if self.direction == 2: self.y[0] = self.y[0] - self.step if self.direction == 3: self.y[0] = self.y[0] + self.step self.updateCount = 0 def moveRight(self): self.direction = 0 def moveLeft(self): self.direction = 1 def moveUp(self): self.direction = 2 def moveDown(self): self.direction = 3 def target(self,dx,dy): if self.x[0] > dx: self.moveLeft() if self.x[0] < dx: self.moveRight() if self.x[0] == dx: if self.y[0] < dy: self.moveDown() if self.y[0] > dy: self.moveUp() def draw(self, surface, image): for i in range(0,self.length): surface.blit(image,(self.x[i],self.y[i])) class Game: def isCollision(self,x1,y1,x2,y2,bsize): if x1 >= x2 and x1 <= x2 + bsize: if y1 >= y2 and y1 <= y2 + bsize: return True return False class App: windowWidth = 800 windowHeight = 600 player = 0 apple = 0 def __init__(self): self._running = True self._display_surf = None self._image_surf = None self._apple_surf = None self.game = Game() self.player = Player(5) self.apple = Apple(8,5) self.computer = Computer(5) def on_init(self): pygame.init() self._display_surf = pygame.display.set_mode((self.windowWidth,self.windowHeight), pygame.HWSURFACE) pygame.display.set_caption('Pygame pythonspot.com example') self._running = True self._image_surf = pygame.image.load("pygame.png").convert() self._apple_surf = pygame.image.load("apple.png").convert() def on_event(self, event): if event.type == QUIT: self._running = False def on_loop(self): self.computer.target(self.apple.x, self.apple.y) self.player.update() self.computer.update() # does snake eat apple? for i in range(0,self.player.length): if self.game.isCollision(self.apple.x,self.apple.y,self.player.x[i], self.player.y[i],44): self.apple.x = randint(2,9) * 44 self.apple.y = randint(2,9) * 44 self.player.length = self.player.length + 1 # does computer eat apple? for i in range(0,self.player.length): if self.game.isCollision(self.apple.x,self.apple.y,self.computer.x[i], self.computer.y[i],44): self.apple.x = randint(2,9) * 44 self.apple.y = randint(2,9) * 44 #self.computer.length = self.computer.length + 1 # does snake collide with itself? for i in range(2,self.player.length): if self.game.isCollision(self.player.x[0],self.player.y[0],self.player.x[i], self.player.y[i],40): print "You lose! Collision: " print "x[0] (" + str(self.player.x[0]) + "," + str(self.player.y[0]) + ")" print "x[" + str(i) + "] (" + str(self.player.x[i]) + "," + str(self.player.y[i]) + ")" exit(0) pass def on_render(self): self._display_surf.fill((0,0,0)) self.player.draw(self._display_surf, self._image_surf) self.apple.draw(self._display_surf, self._apple_surf) self.computer.draw(self._display_surf, self._image_surf) pygame.display.flip() def on_cleanup(self): pygame.quit() def on_execute(self): if self.on_init() == False: self._running = False while( self._running ): pygame.event.pump() keys = pygame.key.get_pressed() if (keys[K_RIGHT]): self.player.moveRight() if (keys[K_LEFT]): self.player.moveLeft() if (keys[K_UP]): self.player.moveUp() if (keys[K_DOWN]): self.player.moveDown() if (keys[K_ESCAPE]): self._running = False self.on_loop() self.on_render() time.sleep (50.0 / 1000.0); self.on_cleanup() if __name__ == "__main__" : theApp = App() theApp.on_execute() ``` ![python snake](img/03294f86324be9f10d0065240bd181ff.jpg) python snake ## 结论 您学习了如何使用非常简单的 AI 算法创建基本的计算机玩家。 [下一步：学习基本的侧滑器逻辑](https://pythonspot.com/jump-and-run-in-pygame/)