├── README.md
└── maze-generator.py


/README.md:
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1 | # Maze Generator
2 | ![Image](https://www.picturepaste.ca/images/2020/05/31/Capture.png)
3 | ## Purpose
4 | To visualize the recursive backtracking algorithm.
5 | 


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/maze-generator.py:
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  1 | import pygame
  2 | import random
  3 | import time
  4 | 
  5 | 
  6 | def cwrap(x):
  7 |     q,r = divmod(x,255)
  8 |     if q%2:
  9 |         return 255-r
 10 |     else:
 11 |         return r
 12 | 
 13 | 
 14 | def removeWalls(a, b):
 15 | 	x = a.x-b.x
 16 | 	y = a.y-b.y
 17 | 
 18 | #Top right bottom left
 19 | 	if(x == -1):#remove right wall of A and left wall of b
 20 | 		a.walls[1] = False
 21 | 		b.walls[3] = False
 22 | 	if(x==1):#Remove left wall of A and right wall of b
 23 | 		a.walls[3] = False
 24 | 		b.walls[1] = False
 25 | 	if(y == -1):#Remove bottom wall of A and top wall of b
 26 | 		a.walls[2] = False
 27 | 		b.walls[0] = False
 28 | 	if(y == 1):#Remove top wall of A and bottom wall of b
 29 | 		a.walls[0] = False
 30 | 		b.walls[2] = False
 31 | 
 32 | 
 33 | 
 34 | class Cell():
 35 | 	def __init__(self, x, y,w, gameDisplay, grid, cols, rows):
 36 | 		self.cols = cols
 37 | 		self.rows = rows
 38 | 		self.x = x
 39 | 		self.y = y
 40 | 		self.w = w
 41 | 		self.gameDisplay = gameDisplay
 42 | 		self.walls = [True, True, True, True] #Top, right, bottom, left
 43 | 		self.visited = False
 44 | 
 45 | 
 46 | 
 47 | 	def show(self):
 48 | 		x_pos = self.x*self.w
 49 | 		y_pos = self.y*self.w
 50 | 
 51 | 		if(self.visited):
 52 | 			col = (cwrap(self.x * 30),
 53 | 			      cwrap(self.y * -10),
 54 | 				  cwrap(self.y * 40))
 55 | 			pygame.draw.rect(gameDisplay,col,(x_pos,y_pos,w,w))
 56 | 		#pygame.draw.rect(gameDisplay,(255,255,255),(x_pos,y_pos,w,w), 1)
 57 | 		if (self.walls[0]):
 58 | 		#Top
 59 | 			pygame.draw.line(gameDisplay, (255,255,255), (x_pos, y_pos), (x_pos+w, y_pos), 1)
 60 | 		if (self.walls[1]):
 61 | 		#Right
 62 | 			pygame.draw.line(gameDisplay, (255, 255,255), (x_pos+w, y_pos), (x_pos+w, y_pos+w), 1)
 63 | 		if (self.walls[2]):
 64 | 		#Bottom
 65 | 			pygame.draw.line(gameDisplay, (255, 255,255), (x_pos, y_pos+w), (x_pos+w, y_pos+w), 1)
 66 | 		if (self.walls[3]):
 67 | 		#Left
 68 | 			pygame.draw.line(gameDisplay, (255, 255,255), (x_pos, y_pos), (x_pos, y_pos+w), 1)
 69 | 
 70 | 		
 71 | 
 72 | 	def checkNeighbours(self):
 73 | 		neighbours = []
 74 | 		if(self.index(self.x, self.y-1)!= -1):
 75 | 			top = grid[self.index(self.x, self.y-1)]
 76 | 
 77 | 			if not top.visited :
 78 | 				neighbours.append(top)
 79 | 		
 80 | 		if(self.index(self.x+1, self.y)!= -1):
 81 | 			right = grid[self.index(self.x+1, self.y)]
 82 | 
 83 | 			if not right.visited:
 84 | 				neighbours.append(right)
 85 | 		
 86 | 		if(self.index(self.x, self.y+1)!= -1):
 87 | 			bottom = grid[self.index(self.x, self.y+1)]
 88 | 
 89 | 			if not bottom.visited:
 90 | 				neighbours.append(bottom)
 91 | 
 92 | 		if(self.index(self.x-1, self.y)!= -1):
 93 | 			left = grid[self.index(self.x-1, self.y)]
 94 | 
 95 | 			if not left.visited:
 96 | 				neighbours.append(left)
 97 | 
 98 | 		#print(top, self.index(self.x, self.y-1))
 99 | 		if(neighbours):
100 | 			return neighbours[random.randint(0, len(neighbours)-1)]
101 | 		else:
102 | 			return None
103 | 
104 | 
105 | 
106 | 	def index(self, x, y):
107 | 		if(x<0 or y<0 or x>self.cols-1 or y>self.rows-1):
108 | 			return -1
109 | 
110 | 		else:
111 | 			return (x+y*self.cols)
112 | 
113 | 	def highlight(self):
114 | 		x_pos = self.x*self.w
115 | 		y_pos = self.y*self.w
116 | 
117 | 		pygame.draw.rect(gameDisplay,(96,50,158),(x_pos,y_pos,w,w))
118 | 
119 | 
120 | if __name__ == "__main__":
121 | 	pygame.init()
122 | 	WIDTH = 600
123 | 	HEIGHT = 600
124 | 
125 | 	w = 10
126 | 	cols = int(WIDTH/w)
127 | 	rows = int(HEIGHT/w)
128 | 	grid = []
129 | 	stack = []
130 | 	
131 | 	gameDisplay = pygame.display.set_mode((WIDTH,HEIGHT))
132 | 	pygame.display.set_caption("Recursive Backtracker Maze Generator")
133 | 
134 | 	for i in range(rows):
135 | 		for j in range(cols):
136 | 			grid.append(Cell(j, i, w, gameDisplay, grid, cols, rows))
137 | 
138 | 
139 | 	current = grid[0]
140 | 
141 | 	clock = pygame.time.Clock()
142 | 
143 | 	exit = False
144 | 	time.sleep(10)
145 | 
146 | 	while not exit:
147 | 		for i in range(len(grid)):
148 | 			grid[i].show()
149 | 
150 | 		#Step 1
151 | 		current.visited = True
152 | 		current.highlight()
153 | 
154 | 		next = current.checkNeighbours()
155 | 
156 | 		if (next != None):
157 | 			next.visited = True
158 | 			#Step 2
159 | 			stack.append(current)
160 | 
161 | 			#Step 3
162 | 			removeWalls(current, next)
163 | 
164 | 
165 | 			#Step 4
166 | 			current = next
167 | 
168 | 
169 | 		elif (len(stack)>0):
170 | 			current = stack.pop()
171 | 
172 | 
173 | 
174 | 		for event in pygame.event.get():
175 | 			if event.type == pygame.QUIT:
176 | 				exit = True
177 | 
178 | 		pygame.display.update()
179 | 		gameDisplay.fill((0,0,0))
180 | 		clock.tick(60)
181 | 	pygame.quit()
182 | 	quit()
183 | 
184 | 
185 | 
186 | 
187 | 


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