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I am still learning how to code and wanted to create a pathfinding visualizer by following this video: https://www.youtube.com/watch?v=JtiK0DOeI4A&ab_channel=TechWithTim

I think i understand the algorithm and the whole code more or less, but i want to expand the program. I want to implement more algorithms, some buttons and a file dialog to import and export labyrinths and stop the time the algorithm takes and some stuff like that. I know how to implement another algorithm, but i am new to Pygame, so i have no idea how to display that. I tried to combined it with PyQt5 and searched for different solutions with Pygame itself, but nothing really worked.

How can i add some bar or something like that above where i can choose the algorithm i want to use with a dropdown menu or similar and import the labyrinth and all that stuff?

This is the corresponding code:

import pygame
import math
from queue import PriorityQueue

RED = (255, 0, 0)
GREEN = (0, 255, 0)
BLUE = (0, 0, 255)
YELLOW = (255, 255, 0)
WHITE = (255, 255, 255)
BLACK = (0, 0, 0)
PURPLE = (128, 0, 128)
ORANGE = (255, 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
        self.y = col * width
        self.color = WHITE
        self.neighbors = []
        self.width = width
        self.total_rows = total_rows

    def get_pos(self):
        return (self.row, self.col)
    
    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_closed(self):
        self.color = RED
    
    def make_open(self):
        self.color = GREEN

    def make_barrier(self):
        self.color = BLACK

    def make_start(self):
        self.color = ORANGE

    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.neightbors = []
        if self.row < self.total_rows -1 and not grid[self.row + 1][self.col].is_barrier(): # DOWN
            self.neightbors.append(grid[self.row + 1][self.col])

        if self.row > 0 and not grid[self.row - 1][self.col].is_barrier(): # UP
            self.neightbors.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.neightbors.append(grid[self.row][self.col + 1])

        if self.col > 0 and not grid[self.row][self.col - 1].is_barrier(): # LEFT
            self.neightbors.append(grid[self.row][self.col - 1])

    def __lt__(self, other):
        return (False)

def h(p1, p2):
    x1, y1 = p1
    x2, y2 = p2
    return (abs(x1 - x2) + abs(y1 - y2))

def reconstruct_path(came_from, current, draw):
    while current in came_from:
        current = came_from[current]
        current.make_path()
        draw()

def algorithm(draw, grid, start, end):
    count = 0
    open_set = PriorityQueue()
    open_set.put((0, count, start))
    came_from = {}
    g_score = {spot: float ("inf") for row in grid for spot in row}
    g_score[start] = 0
    f_score = {spot: float ("inf") for row in grid for spot in row}
    f_score[start] = h(start.get_pos(), end.get_pos())

    open_set_hash = {start}

    while not open_set.empty():
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                pygame.quit()

        current = open_set.get()[2]
        open_set_hash.remove(current)

        if current == end: # draws the path
            reconstruct_path(came_from, end, draw)
            end.make_end()
            return True

        for neighbor in current.neightbors:
            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
                    
def make_grid(rows, width):
    grid = []
    gap = width // rows
    for i in range(rows):
        grid.append([])
        for j in range(rows):
            spot = Spot(i, j, gap, rows)
            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))
        for j in range(rows):
            pygame.draw.line(win, GREY, (j * gap, 0), (j * gap, width))

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():
    width = 800
    win = pygame.display.set_mode((width, width))
    pygame.display.set_caption("A* Path Finding Algorithm")


    ROWS = 50
    grid = make_grid(ROWS, width)

    start = None
    end = None

    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]:
                pos = pygame.mouse.get_pos()
                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]:
                pos = pygame.mouse.get_pos()
                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:
                if event.key == pygame.K_SPACE and start and end:
                    for row in grid:
                        for spot in row:
                            spot.update_neighbors(grid)
                    
                    algorithm(lambda: draw(win, grid, ROWS, width), grid, start, end)

                if event.key == pygame.K_c:
                    start = None
                    end = None
                    grid = make_grid(ROWS, width)

    pygame.quit()

if __name__ == "__main__":
    main()
Rabbid76
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Marvin
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  • Look at this topic in order to make buttons : https://stackoverflow.com/questions/47639826/pygame-button-single-click . However, during all years I used pygame I never saw a specific method to make a bar like you said. The only way that comes to my mind is to make multiples loop that begin if the player click on a button in order to add several alogirthms. And drawing rectangles on each algorithm is, in my mind, the best way to make a fake "task bar". Notice me if you want me to write a little example. – Æ’kS124 Jan 03 '21 at 15:03
  • Related [tips on Adding/creating a drop down selection box in pygame](https://stackoverflow.com/questions/19877900/tips-on-adding-creating-a-drop-down-selection-box-in-pygame/65397627#65397627) and [trying creating dropdown menu pygame, but got stuck](https://stackoverflow.com/questions/59236523/trying-creating-dropdown-menu-pygame-but-got-stuck/65369938#65369938) – Rabbid76 Jan 03 '21 at 15:15
  • 2
    The title of your question has nothing to do with your question. You're looking for UI elements, but not pathfinding. – Rabbid76 Jan 03 '21 at 15:51

0 Answers0