python pygame 游戏实战:Maze 迷宫生成，显示和游戏（附全部代码）

生成迷宫(maze)的算法有很多种，论坛上有很多这方面的资料可以参考。  这里使用回溯法(backtracking)，主要参考Build a 2-player maze game with Python Part 4 - Coding TidBits 

用的是迭代函数(recursive function): 不断寻找周边没有走过的网格(cell), 并随机打通任一边的”墙（wall)".  如果设定SHOW_DRAW = True的话， 可以图像显示整个回溯法过程。 迷宫生成结束后， 图像显示， 并加上一个红球代表玩家， 红球可以走过整个迷宫， 玩法方面， 可以计算红球通过整个迷宫的时间。迷宫的复杂程度可以通过设定其行和列数， 如MAZE_COLS=15， MAZE_ROWS=13

全部代码如下：

import random
import pygame
import numpy as np

#Ref；http://www.danduda.com/blog/2018/11/18/Build-a-2-player-maze-game-with-Python-Part-4/
UP,DOWN=-1,1
LEFT,RIGHT=-2,2

SCREEN_WIDTH = 800
SCREEN_HEIGHT = 600

MAZE_COLS=15
MAZE_ROWS=13
WALL_SIZE = int(120/max(MAZE_COLS,MAZE_ROWS))  # Pixel size/Wall thickness
WT=WALL_SIZE #used in pygame.time.wait(WT)
CELL_SIZE=4*WALL_SIZE #a cell has only 2 walls: DOWN, RIGHT
MAZE_WIDTH =CELL_SIZE * MAZE_COLS +WALL_SIZE  
MAZE_HEIGHT = CELL_SIZE *MAZE_ROWS+ WALL_SIZE

TOPLEFT_X,TOPLEFT_Y = (SCREEN_WIDTH // 2 - MAZE_WIDTH // 2, SCREEN_HEIGHT // 2 - MAZE_HEIGHT // 2)
x_offset = TOPLEFT_X + WALL_SIZE
y_offset = TOPLEFT_Y + WALL_SIZE   

WALL_COLOR = (18, 94, 32)
MAZE_COLOR = (255, 255, 255)
UNVISITED_COLOR = (0, 0, 0)
PLAYER_COLOR = (255, 0, 0)

SHOW_DRAW = True

class Cell():
    def __init__(self,r,c):
        self.r=r
        self.c=c
        self.visited=False    #True-just visited, not open any wall
        self.walls={UP:False,DOWN:False,LEFT:False,RIGHT:False}
 
class Maze():
    def __init__(self,row=MAZE_ROWS,col=MAZE_COLS):
        self.row=row
        self.col=col
        self.maze= [[Cell(r,c) for c in range(col)] for r in range(row)]
        self.make()       
        self.player= Player(PLAYER_COLOR, (WALL_SIZE * 3) // 2 )                                     
        self.player_sprite = pygame.sprite.RenderPlain(self.player)                    
    def make(self,r0=0,c0=0):    
        direction = {UP: (-1, 0),DOWN: (1, 0),LEFT:(0, -1),RIGHT:(0, 1)}
        current_cell=self.maze[r0][c0]        
        current_cell.visited=True 
        visited_stack=[current_cell]        
        while visited_stack:
            current_cell=visited_stack[-1]  
            un_visited=[]   #unvisited neighbours
            for d, (dr, dc) in direction.items():
                r, c = current_cell.r + dr, current_cell.c + dc
                if (0 <= r < self.row) and (0 <= c < self.col):
                    cell = self.maze[r][c]
                    if not cell.visited:   
                        un_visited.append((d,cell))                     
            if un_visited:                              
                dc,nc=random.choice(un_visited)
                current_cell.walls[dc]=True  #this direction is open
                nc.visited=True
                nc.walls[-dc]=True  
                visited_stack.append(nc)           
            elif len(visited_stack):
                visited_stack.pop()
                
            if SHOW_DRAW:
                self.draw_maze()
                pygame.display.update()
                pygame.time.wait(WT)
                pygame.event.pump()       
              
        #self.maze[0][0].walls[LEFT]=True
        #self.maze[self.row-1][self.col-1].walls[RIGHT] = True 
     
    def draw_maze(self):        
        screen.fill('black')
        pygame.draw.rect(screen, WALL_COLOR, (TOPLEFT_X, TOPLEFT_Y, MAZE_WIDTH, MAZE_HEIGHT))                                        
        for c in range(MAZE_COLS):      #colums 5 x-c
            for r in range(MAZE_ROWS):  # rows 3 y-r
                cell=self.maze[r][c]    
                x=c*CELL_SIZE+ x_offset
                y=r*CELL_SIZE + y_offset
                if cell.visited:                    
                     pygame.draw.rect(screen, MAZE_COLOR, (x, y,3*WALL_SIZE, 3*WALL_SIZE))                                           
                else:                             
                     pygame.draw.rect(screen, UNVISITED_COLOR,(x, y,3*WALL_SIZE, 3*WALL_SIZE)) 
                if cell.walls[DOWN]:
                     pygame.draw.rect(screen, MAZE_COLOR, (x, y+3*WALL_SIZE ,3*WALL_SIZE, WALL_SIZE))                         
                if cell.walls[RIGHT]:
                     pygame.draw.rect(screen, MAZE_COLOR, (x+3*WALL_SIZE, y, WALL_SIZE, 3*WALL_SIZE))
                                 
                                
            
    def can_move(self, direction):
        c=self.player.c
        r=self.player.r
        return self.maze[r][c].walls[direction]        
    def move_up(self):
        if self.can_move(UP):
            self.player.r-=1
    def move_right(self):
        if self.can_move(RIGHT):
            self.player.c+=1
    def move_down(self):
        if self.can_move(DOWN):
            self.player.r+=1
    def move_left(self):
        if self.can_move(LEFT): 
            self.player.c-=1    
 
    def checkEvents(self):
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                exit()   
            keys = pygame.key.get_pressed()
            if keys[pygame.K_LEFT]:
                self.move_left()
            if keys[pygame.K_RIGHT]:
                self.move_right()
            if keys[pygame.K_UP]:
                self.move_up()
            if keys[pygame.K_DOWN]:
                self.move_down()                
    def update(self):
        self.draw_maze()     
        #self.draw_grid()
        self.player.update()
        self.player_sprite.draw(screen)                              

class Player(pygame.sprite.Sprite):
    def __init__(self, color, radius, r=0, c=0):
        # Call the parent class (Sprite) constructor
        super().__init__()
        self.r = r
        self.c = c
        self.image = pygame.Surface([radius * 2, radius * 2])
        self.image.fill(MAZE_COLOR)
        self.image.set_colorkey(MAZE_COLOR)
        pygame.draw.circle(self.image, color, (radius, radius), radius)                  
        self.rect = self.image.get_rect()
        self.update() 
    def update(self):
        self.rect.x = x_offset+self.c*CELL_SIZE
        self.rect.y = y_offset+self.r*CELL_SIZE
            
pygame.init()
screen=pygame.display.set_mode((SCREEN_WIDTH,SCREEN_HEIGHT))
A=Maze()
while 1:
    screen.fill((0,0,0))
    A.checkEvents()
    A.update()
    pygame.display.update()