小组任务，贪吃蛇游戏代码

  1 #!/usr/bin/env python3
  2 # -*- coding: utf-8 -*-
  3 from sys import exit#调用exit函数，用于终止python程序
  4 from random import choice#调用choice函数，返回一个列表，元组或字符串的随机项
  5 
  6 import pygame#调用pygame库
  7 from pygame.locals import QUIT, KEYDOWN#调用quit(用于退出python),keydown函数(触发按下某键时的功能)
  8 
  9 TITLE = ‘贪吃蛇--Transfer by 逗比小青年‘
 10 
 11 WIDTH = 660#宽度
 12 HEIGHT = 500#长度
 13 SNAKE_SIZE = 20#每一块蛇的大小
 14 BOARD_COLOR = (0, 0, 100)#底板颜色
 15 
 16 
 17 class Vector():
 18     def __init__(self, x, y):
 19         self._x = x
 20         self._y = y
 21 
 22     @property
 23     def x(self):
 24         return self._x
 25 
 26     @property
 27     def y(self):
 28         return self._y
 29 
 30     @x.setter
 31     def x(self, value):
 32         self._x = value
 33 
 34     @y.setter
 35     def y(self, value):
 36         self._y = value
 37 
 38     def __len__(self):#返回集合长度
 39         return 2
 40 
 41     def __getitem__(self, index):#getitem用于输出序列属性中的某个元素
 42         if index == 0:
 43             return self.x
 44         if index == 1:
 45             return self.y
 46         raise IndexError#raise 关键字用于引发一个异常，即程序出现错误后，程序内部会显示"IndexError"
 47 
 48     def copy(self):#复制对象子列
 49         type_self = type(self)
 50         return type_self(self.x, self.y)
 51 
 52     def move(self, other):#运动函数
 53         if isinstance(other, Vector):#isinstance() 函数用来判断一个对象是否是一个已知的类型
 54             self.x += other.x
 55             self.y += other.y
 56         else:
 57             self.x += other
 58             self.y += other
 59         return self
 60 
 61     def __eq__(self, other):
 62         if isinstance(other, Vector):
 63             return self.x == other.x and self.y == other.y
 64         return NotImplemented
 65 
 66     def __ne__(self, other):
 67         if isinstance(other, Vector):
 68             return self.x != other.x or self.y != other.y
 69         return NotImplemented
 70 
 71     def __repr__(self):#repr() 函数将对象转化为供解释器读取的形式
 72         type_self = type(self)
 73         name = type_self.__name__
 74         return ‘{}({!r}, {!r})‘.format(name, self.x, self.y)
 75 
 76 
 77 class Snake:
 78     def __init__(self):
 79         self.map = {(x, y): 0
 80                     for x in range(1,
 81                                    int(WIDTH / SNAKE_SIZE) - 2)
 82                     for y in range(1,
 83                                    int(HEIGHT / SNAKE_SIZE) - 2)}
 84         self.body = [
 85             Vector(5 * SNAKE_SIZE, 5 * SNAKE_SIZE),
 86             Vector(6 * SNAKE_SIZE, 5 * SNAKE_SIZE)
 87         ]
 88         self.head = self.body[-1].copy()
 89         self.color = (0, 0, 0)
 90         self.direction = {
 91             ‘right‘: Vector(SNAKE_SIZE, 0),
 92             ‘left‘: Vector(-SNAKE_SIZE, 0),
 93             ‘up‘: Vector(0, -SNAKE_SIZE),
 94             ‘down‘: Vector(0, SNAKE_SIZE)
 95         }
 96         self.move_direction = ‘right‘
 97         self.speed = 4
 98         self.score = 0
 99         self.food = Vector(0, 0)
100         self.food_color = (255, 0, 0)
101         self.generate_food()
102         self.game_started = False
103 
104     def generate_food(self):#食物生成
105         empty_pos = [
106             pos for pos in self.map.keys()
107             if Vector(pos[0] * SNAKE_SIZE, pos[1] *
108                       SNAKE_SIZE) not in self.body
109         ]
110         result = choice(empty_pos)
111         self.food.x = result[0] * 20
112         self.food.y = result[1] * 20
113 
114     def move(self):#移动中的进食过程与死亡判断
115         self.head = self.body[-1].copy()
116         self.head.move(self.direction[self.move_direction])
117         if not self._islive(self.head):
118             return False
119 
120         self.body.append(self.head)
121 
122         if self.head == self.food:
123             self.score += 1
124             if self.score % 5 == 0:
125                 self.speed += 2
126             self.generate_food()
127         else:
128             self.body.pop(0)
129         return True
130 
131     def _islive(self, head):#死亡定义
132         return 0 < head.x < WIDTH - SNAKE_SIZE and 0 < head.y < HEIGHT - SNAKE_SIZE and head not in self.body
133 
134 
135 KEY_DIRECTION_DICT = {#操控键位定义
136     119: ‘up‘,  # W
137     115: ‘down‘,  # S
138     97: ‘left‘,  # A
139     100: ‘right‘,  # D
140     273: ‘up‘,  # UP
141     274: ‘down‘,  # DOWN
142     276: ‘left‘,  # LEFT
143     275: ‘right‘,  # RIGHT
144 }
145 
146 
147 def press(events, snake):
148     for event in events:
149         if event.type == QUIT:
150             exit()
151         if event.type == KEYDOWN:
152             if event.key == 13:
153                 snake.game_started = True
154             if snake.game_started and event.key in KEY_DIRECTION_DICT:
155                 return direction_check(snake.move_direction,
156                                        KEY_DIRECTION_DICT[event.key])
157 
158 
159 def draw_score(screen, score, position):#实时分数显示
160     tips_font = pygame.font.SysFont(‘arial‘, 20)
161     screen.blit(
162         tips_font.render(‘Score: {}‘.format(score), True, (0, 0, 205),
163                          (255, 255, 255)), position)
164 
165 
166 def game_continue(screen, snake):
167     init_board(screen)
168     draw_score(screen, snake.score, (500, 0))
169     for seg in snake.body:
170         pygame.draw.rect(screen, snake.color, [seg[0], seg[1], 20, 20], 0)
171     pygame.draw.rect(screen, snake.food_color,
172                      [snake.food[0], snake.food[1], 20, 20], 0)
173 
174 
175 def game_over(screen, fonts, score):
176     screen.blit(fonts[‘game_over‘], (250, 100))
177     draw_score(screen, score, (290, 200))
178     screen.blit(fonts[‘start‘], (220, 310))
179     snake = Snake()
180     return snake
181 
182 
183 def direction_check(move_direction, change_direction):#键位感知
184     directions = [[‘up‘, ‘down‘], [‘left‘, ‘right‘]]
185     if move_direction in directions[0] and change_direction in directions[1]:
186         return change_direction
187     elif move_direction in directions[1] and change_direction in directions[0]:
188         return change_direction
189 
190     return move_direction
191 
192 
193 def init(fonts):#游戏界面文字布置
194     fps_clock = pygame.time.Clock()
195     pygame.display.set_caption(TITLE)
196     screen = pygame.display.set_mode((WIDTH, HEIGHT), 0, 32)
197     screen.fill((255, 255, 255))
198     screen.blit(fonts[‘welcome‘], (177, 100))
199     screen.blit(fonts[‘start‘], (195, 310))
200     return fps_clock, screen
201 
202 
203 def init_board(screen):#边框定制
204     board_width = int(WIDTH / SNAKE_SIZE)
205     board_height = int(HEIGHT / SNAKE_SIZE)
206     color = BOARD_COLOR
207     width = 0
208     for i in range(board_width):
209         pos = i * SNAKE_SIZE, 0, SNAKE_SIZE, SNAKE_SIZE
210         pygame.draw.rect(screen, color, pos, width)
211         pos = i * SNAKE_SIZE, (board_height -
212                                1) * SNAKE_SIZE, SNAKE_SIZE, SNAKE_SIZE
213         pygame.draw.rect(screen, color, pos, width)
214 
215     # 上下边框占用了 Y: 0 26*20
216     for i in range(board_height - 1):
217         pos = 0, SNAKE_SIZE + i * SNAKE_SIZE, SNAKE_SIZE, SNAKE_SIZE
218         pygame.draw.rect(screen, color, pos, width)
219         pos = (
220             board_width - 1
221         ) * SNAKE_SIZE, SNAKE_SIZE + i * SNAKE_SIZE, SNAKE_SIZE, SNAKE_SIZE
222         pygame.draw.rect(screen, color, pos, width)
223 
224 
225 def font_setting():#游戏初始，游戏结束，游戏胜利界面文字布置
226     title_font = pygame.font.SysFont(‘arial‘, 32)
227     welcome_words = title_font.render(‘Welcome to My Snake‘, True, (0, 0, 0),
228                                       (255, 255, 255))
229     tips_font = pygame.font.SysFont(‘arial‘, 24)
230     start_game_words = tips_font.render(‘Press Enter to Start Game‘, True,
231                                         (0, 0, 0), (255, 255, 255))
232     gameover_words = title_font.render(‘GAME OVER‘, True, (205, 92, 92),
233                                        (255, 255, 255))
234     win_words = title_font.render(‘THE SNAKE IS LONG ENOUGH AND YOU WIN!‘,
235                                   True, (0, 0, 205), (255, 255, 255))
236     return {
237         ‘welcome‘: welcome_words,
238         ‘start‘: start_game_words,
239         ‘game_over‘: gameover_words,
240         ‘win‘: win_words
241     }
242 
243 
244 def main():
245     pygame.init()
246     fonts = font_setting()
247     fps_clock, screen = init(fonts)
248 
249     snake = Snake()
250     direction = snake.move_direction
251     while True:
252         events = pygame.event.get()
253         new_direction = press(events, snake)
254         if snake.game_started:
255             if new_direction:
256                 snake.move_direction = new_direction
257             screen.fill((255, 255, 255))
258             if not snake.move():
259                 snake = game_over(screen, fonts, snake.score)
260                 direction = snake.move_direction
261             else:
262                 game_continue(screen, snake)
263         pygame.display.update()
264         fps_clock.tick(snake.speed)
265     
266 
267 
268 if __name__ == ‘__main__‘:
269     main()