Newer
Older
import pygame
import math
from queue import PriorityQueue
WIDTH = 800
WIN = pygame.display.set_mode((WIDTH, WIDTH))
pygame.display.set_caption("Pathfinder Visualizer")
# colors
RED = (255, 0, 0 )
GREEN = (0, 255, 0)
BLUE = (0, 255, 0)
YELLOW = (255, 255, 0 )
WHITE = (255, 255, 255)
BLACK = (0, 0 , 0)
PURPLE = (128, 0, 128)
ORANGE = (225, 165, 0)
GREY = (128, 128, 128)
TURQUOISE = (64, 224, 208)
class Spot:
def __init__(self, row, col, width, total_rows):
self.row = row
self.col = col
self.x = row * width # row number 8 the width of each spot
self.y = col * width
self.color = WHITE
self.neighbors = []
self.width = width
self.total_rows = total_rows
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
def get_pos(self):
return self.row, self.col
# already looked at ?
def is_closed(self):
return self.color == RED
def is_open(self):
return self.color == GREEN
def is_barrier(self):
return self.color == BLACK
def is_start(self):
return self.color == ORANGE
def is_end(self):
return self.color == TURQUOISE
def reset(self):
self.color = WHITE
def make_start(self):
self.color = ORANGE
def make_closed(self):
self.color = RED
def make_open(self):
self.color = GREEN
def make_barrier(self):
self.color = BLACK
def make_end(self):
self.color = TURQUOISE
def make_path(self):
self.color = PURPLE
def draw(self, win):
pygame.draw.rect(win, self.color, (self.x, self.y, self.width, self.width))
def update_neighbors(self, grid):
self.neighbors = []
if self.row < self.total_rows -1 and not grid[self.row + 1][self.col].is_barrier(): # DOWN
self.neighbors.append(grid[self.row + 1][self.col])
if self.row > 0 and not grid[self.row - 1][self.col].is_barrier(): # UP
self.neighbors.append(grid[self.row - 1][self.col])
if self.col < self.total_rows -1 and not grid[self.row][self.col + 1].is_barrier(): # RIGHT
self.neighbors.append(grid[self.row][self.col + 1])
if self.col > 0 and not grid[self.row][self.col - 1].is_barrier(): # LEFT
self.neighbors.append(grid[self.row][self.col - 1])
def __lt__(self,other):
return False
# heuiristic function
def h(p1, p2):
x1, y1 = p1 # deconstruct p1
x2, y2 = p2 # deconstruct p2
return abs(x1-x2) + abs(y1-y2)
def reconstruct_path(came_from, current, draw):
# current starts from the end node and we'll traverse to the start node
while current in came_from:
current = came_from[current]
current.make_path()
draw()
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
draw() # Lamda is a anonym function so can call like this
count = 0
open_set = PriorityQueue() # always gets the smallest element everytime out of it
open_set.put((0, count, start))
came_from = {}
g_score = {spot: float("inf") for row in grid for spot in row} # for row in grid, for spot in row => g_score[spot] = float("inf")
g_score[start] = 0
f_score = {spot: float("inf") for row in grid for spot in row} # for row in grid, for spot in row => f_score[spot] = float("inf")
f_score[start] = h(start.get_pos(), end.get_pos()) # 0 + h
open_set_hash = {start}
while not open_set.empty():
# make sure we're not quitting the game, if we are then quit
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
current = open_set.get()[2] # gets the min fscore related node from the priority queue
open_set_hash.remove(current)
if current == end:
reconstruct_path(came_from, end, draw)
end.make_end()
return True
for neighbor in current.neighbors:
temp_g_score = g_score[current] + 1
if temp_g_score < g_score[neighbor]:
came_from[neighbor] = current
g_score[neighbor] = temp_g_score
f_score[neighbor] = temp_g_score + h(neighbor.get_pos(), end.get_pos())
if neighbor not in open_set_hash:
count += 1
open_set.put((f_score[neighbor], count, neighbor))
open_set_hash.add(neighbor)
neighbor.make_open()
draw()
if current != start:
current.make_closed()
return False
draw() # Lamda is a anonym function so can call like this
stack = [(start, None)] # node of node and its parent
visited = set() # to avoid duplicacy
parents = {} # dict to store parent information
# while set is not empty
while stack:
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
current, parent = stack.pop()
visited.add(current)
# check if we reached the goal
if current == end:
reconstruct_path_dfs_bfs(start, end, parents, draw) # Pass the required arguments directly
end.make_end()
return True
for neighbor in current.neighbors:
if neighbor not in visited and not neighbor.is_barrier():
stack.append((neighbor, current))
neighbor.make_open()
parents[neighbor] = current
draw()
if current != start:
current.make_closed()
return False
def reconstruct_path_dfs_bfs(start, end, parents, draw,): # Pass the required arguments directly
current = end
while current != start:
current.make_path()
draw()
current = parents[current]
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
def bfs(draw, grid, start, end, ROWS):
draw()
queue = [start]
visited = set()
parents = {}
while queue:
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
current = queue.pop(0)
if current == end:
reconstruct_path_dfs_bfs(start, end, parents, draw)
end.make_end()
return True
for neighbor in current.neighbors:
if neighbor not in visited and not neighbor.is_barrier():
queue.append(neighbor)
visited.add(neighbor)
neighbor.make_open()
parents[neighbor] = current
draw()
if current != start:
current.make_closed()
return False
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
# A* without heuristics
# The g-score represents the cost of the path from the start node to the current node.
def dijkstra(draw, grid, start, end):
draw() # Lamda is a anonym function so can call like this
count = 0
open_set = PriorityQueue() # always gets the smallest element everytime out of it
open_set.put((0, count, start))
came_from = {}
g_score = {spot: float("inf") for row in grid for spot in row} # for row in grid, for spot in row => g_score[spot] = float("inf")
g_score[start] = 0
while not open_set.empty():
# make sure we're not quitting the game, if we are then quit
for event in pygame.event.get():
if event.type == pygame.QUIT:
pygame.quit()
current = open_set.get()[2] # gets the min gscore related node from the priority queue
if current == end:
reconstruct_path(came_from, end, draw)
end.make_end()
return True
for neighbor in current.neighbors:
temp_g_score = g_score[current] + 1
if temp_g_score < g_score[neighbor]:
came_from[neighbor] = current
g_score[neighbor] = temp_g_score
if neighbor not in open_set.queue:
count += 1
open_set.put((g_score[neighbor], count, neighbor))
neighbor.make_open()
draw()
if current != start:
current.make_closed()
return False
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
def make_grid(rows, width):
grid = []
gap = width // rows # the width of each cube
for i in range(rows):
grid.append([])
for j in range(rows):
spot = Spot(i, j, gap, rows) # i and j are current row, col for that spot and gap is the width of each Spot
grid[i].append(spot)
return grid
def draw_grid(win, rows, width):
gap = width // rows
for i in range(rows):
pygame.draw.line(win, GREY, (0, i*gap), (width, i * gap)) # horizontal lines
for j in range(rows):
pygame.draw.line(win, GREY, (j*gap, 0), (j * gap, width)) # vertical lines
def draw(win, grid, rows, width):
win.fill(WHITE)
for row in grid:
for spot in row:
spot.draw(win)
draw_grid(win, rows, width)
pygame.display.update()
def get_clicked_pos(pos, rows, width):
gap = width // rows
y,x = pos
row = y // gap
col = x // gap
return row,col
def main(win, width):
ROWS = 50
grid = make_grid(ROWS, width)
start = None
end = None
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
run = True
while run:
draw(win, grid, ROWS, width)
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
if pygame.mouse.get_pressed()[0]: # left click
pos = pygame.mouse.get_pos() # x, y coord of the click
row, col = get_clicked_pos(pos, ROWS, width)
spot = grid[row][col]
if not start and spot!=end:
start = spot
start.make_start()
elif not end and spot!=start:
end = spot
end.make_end()
elif spot != end and spot != start:
spot.make_barrier()
elif pygame.mouse.get_pressed()[2]: # right click
pos = pygame.mouse.get_pos() # x, y coord of the click
row, col = get_clicked_pos(pos, ROWS, width)
spot = grid[row][col]
spot.reset()
if spot == start:
start = None
elif spot == end:
end = None
if event.type == pygame.KEYDOWN:
for row in grid:
for spot in row:
spot.update_neighbors(grid)
if event.key == pygame.K_d and start and end:
# Execute DFS when the "D" key is pressed
dfs(lambda: draw(win, grid, ROWS, width), grid, start, end, ROWS)
if event.key == pygame.K_a and start and end:
# Execute A* when the "A" key is pressed
a_star(lambda: draw(win, grid, ROWS, width), grid, start, end)
if event.key == pygame.K_b and start and end:
bfs(lambda: draw(win, grid, ROWS, width), grid, start, end, ROWS)
if event.key == pygame.K_j and start and end:
dijkstra(lambda: draw(win, grid, ROWS, width), grid, start, end)