Labyrinths and mazes

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http://xahlee.info/comp/unicode_drawing_shapes.html by Xah Lee

Situationist Times #04: International Labyrinth Edition

Jacqueline de Jong (one of the makers of the Situationist Times) talking about printed mazes with overlay.

The PDFs of the Situationist Times are available on Monoskop!

10 PRINT

Nick Montfort and others compilation of maze generation and other simple scripts from early home computing.

https://hub.xpub.nl/bootleglibrary/book/583

Some links to nice parts:

• Including what is a maze, and the ever useful (controversial?) distinction between maze and labyrinth...

The terms “maze” and “labyrinth” are generally synonyms in colloquial English. Still, many scholars and historians have argued over the distinction between these two terms. In the most popular proposed distinction, “labyrinth” refers only to single-path (unicursal) structures, while “maze” refers only to branching-path (multicursal) structures.In this book, the terms “maze” and “labyrinth” are not used to distinguish two different categories of structure or image. Instead, the two terms indicate a single conceptual category, with this book primarily using the term “maze” for both

• the map from Atari adventure,
• the (missing) Vera Molnar work but which you can see online,
• the commodore keyboard and the PETSCII table in the manual

AND an interesting link to the conversation about popular culture and the middle-class:

Fun With Python #1: Maze Generator

This notebook is based on the Medium article "Fun with Python part 1: Maze Generator" written by Orestis Zekai in 2020.

It is a nice tutorial which talks you through a Python implementation of a maze generator.

You can find the tutorial here: https://medium.com/swlh/fun-with-python-1-maze-generator-931639b4fb7e

The maze generator is based on a randomized version of Prim's algorithm, which is one of the maze algorithms that is used to generate a maze:

• Start with a grid full of walls.
• Pick a cell, mark it as part of the maze. Add the walls of the cell to the wall list.
• While there are walls in the list:
  • Pick a random wall from the list. If only one of the cells that the wall divides is visited, then:
    • Make the wall a passage and mark the unvisited cell as part of the maze.
    • Add the neighboring walls of the cell to the wall list.
  • Remove the wall from the list.

Generating mazes on paper

from IPython.display import IFrame
IFrame("maze-generator-on-paper.pdf", width=600, height=400)

Maze Generator

The code below is a slightly adapted version of maze.py written by Orestis Zekai: https://github.com/OrWestSide/python-scripts/blob/master/maze.py

You can use the code to generate custom mazes.

Change the following variables in the code, to make your maze bigger or smaller and to change how your maze looks like!

# --------------------------
wall_tile = "▓"
cell_tile = "░"
height = 11
width = 27
# --------------------------

NOTE: The code below is a slightly different version of the code from the tutorial. The variable names are changed in the double for-loops, to make them connect to the other canvas examples in the other notebooks. For example, a for loop to move block by block through the maze is written below in the following way, using y and x to refer to the coordinates of a block:

for y in range(height):
        for x in range(width):
            if (maze[y][x] == "u"):
                print(unvisited, end="")

# Maze generator -- Randomized Prim Algorithm

## Imports
import random

## Functions
def printMaze(maze):
    for y in range(height):
        for x in range(width):
            if (maze[y][x] == "u"):
                print(unvisited, end="")
            elif (maze[y][x] == "c"):
                print(cell_tile, end="")
            else:
                print(wall_tile, end="")
            
        print("")

# Find number of surrounding cells
def surroundingCells(rand_wall):
    s_cells = 0
    if (maze[rand_wall[0]-1][rand_wall[1]] == "c"):
        s_cells += 1
    if (maze[rand_wall[0]+1][rand_wall[1]] == "c"):
        s_cells += 1
    if (maze[rand_wall[0]][rand_wall[1]-1] == "c"):
        s_cells +=1
    if (maze[rand_wall[0]][rand_wall[1]+1] == "c"):
        s_cells += 1

    return s_cells

## Main code

# Init variables
# --------------------------
wall_tile = "▓"
cell_tile = "░"
height = 11
width = 27
# --------------------------
wall = "w"
cell = "c"
unvisited = "u"
maze = []

# Denote all cells as unvisited
for y in range(height):
    line = []
    for x in range(width):
        line.append(unvisited)
    maze.append(line)

# Randomize starting point and set it a cell
starting_height = int(random.random()*height)
starting_width = int(random.random()*width)
if (starting_height == 0):
    starting_height += 1
if (starting_height == height-1):
    starting_height -= 1
if (starting_width == 0):
    starting_width += 1
if (starting_width == width-1):
    starting_width -= 1

# Mark it as cell and add surrounding walls to the list
maze[starting_height][starting_width] = cell
walls = []
walls.append([starting_height - 1, starting_width])
walls.append([starting_height, starting_width - 1])
walls.append([starting_height, starting_width + 1])
walls.append([starting_height + 1, starting_width])

# Denote walls in maze
maze[starting_height-1][starting_width] = "w"
maze[starting_height][starting_width - 1] = "w"
maze[starting_height][starting_width + 1] = "w"
maze[starting_height + 1][starting_width] = "w"

while (walls):
    # Pick a random wall
    rand_wall = walls[int(random.random()*len(walls))-1]

    # Check if it is a left wall
    if (rand_wall[1] != 0):
        if (maze[rand_wall[0]][rand_wall[1]-1] == "u" and maze[rand_wall[0]][rand_wall[1]+1] == "c"):
            # Find the number of surrounding cells
            s_cells = surroundingCells(rand_wall)

            if (s_cells < 2):
                # Denote the new path
                maze[rand_wall[0]][rand_wall[1]] = "c"

                # Mark the new walls
                # Upper cell
                if (rand_wall[0] != 0):
                    if (maze[rand_wall[0]-1][rand_wall[1]] != "c"):
                        maze[rand_wall[0]-1][rand_wall[1]] = "w"
                    if ([rand_wall[0]-1, rand_wall[1]] not in walls):
                        walls.append([rand_wall[0]-1, rand_wall[1]])

                # Bottom cell
                if (rand_wall[0] != height-1):
                    if (maze[rand_wall[0]+1][rand_wall[1]] != "c"):
                        maze[rand_wall[0]+1][rand_wall[1]] = "w"
                    if ([rand_wall[0]+1, rand_wall[1]] not in walls):
                        walls.append([rand_wall[0]+1, rand_wall[1]])

                # Leftmost cell
                if (rand_wall[1] != 0): 
                    if (maze[rand_wall[0]][rand_wall[1]-1] != "c"):
                        maze[rand_wall[0]][rand_wall[1]-1] = "w"
                    if ([rand_wall[0], rand_wall[1]-1] not in walls):
                        walls.append([rand_wall[0], rand_wall[1]-1])

            # Delete wall
            for wall in walls:
                if (wall[0] == rand_wall[0] and wall[1] == rand_wall[1]):
                    walls.remove(wall)

            continue

    # Check if it is an upper wall
    if (rand_wall[0] != 0):
        if (maze[rand_wall[0]-1][rand_wall[1]] == "u" and maze[rand_wall[0]+1][rand_wall[1]] == "c"):

            s_cells = surroundingCells(rand_wall)
            if (s_cells < 2):
                # Denote the new path
                maze[rand_wall[0]][rand_wall[1]] = "c"

                # Mark the new walls
                # Upper cell
                if (rand_wall[0] != 0):
                    if (maze[rand_wall[0]-1][rand_wall[1]] != "c"):
                        maze[rand_wall[0]-1][rand_wall[1]] = "w"
                    if ([rand_wall[0]-1, rand_wall[1]] not in walls):
                        walls.append([rand_wall[0]-1, rand_wall[1]])

                # Leftmost cell
                if (rand_wall[1] != 0):
                    if (maze[rand_wall[0]][rand_wall[1]-1] != "c"):
                        maze[rand_wall[0]][rand_wall[1]-1] = "w"
                    if ([rand_wall[0], rand_wall[1]-1] not in walls):
                        walls.append([rand_wall[0], rand_wall[1]-1])

                # Rightmost cell
                if (rand_wall[1] != width-1):
                    if (maze[rand_wall[0]][rand_wall[1]+1] != "c"):
                        maze[rand_wall[0]][rand_wall[1]+1] = "w"
                    if ([rand_wall[0], rand_wall[1]+1] not in walls):
                        walls.append([rand_wall[0], rand_wall[1]+1])

            # Delete wall
            for wall in walls:
                if (wall[0] == rand_wall[0] and wall[1] == rand_wall[1]):
                    walls.remove(wall)

            continue

    # Check the bottom wall
    if (rand_wall[0] != height-1):
        if (maze[rand_wall[0]+1][rand_wall[1]] == "u" and maze[rand_wall[0]-1][rand_wall[1]] == "c"):

            s_cells = surroundingCells(rand_wall)
            if (s_cells < 2):
                # Denote the new path
                maze[rand_wall[0]][rand_wall[1]] = "c"

                # Mark the new walls
                if (rand_wall[0] != height-1):
                    if (maze[rand_wall[0]+1][rand_wall[1]] != "c"):
                        maze[rand_wall[0]+1][rand_wall[1]] = "w"
                    if ([rand_wall[0]+1, rand_wall[1]] not in walls):
                        walls.append([rand_wall[0]+1, rand_wall[1]])
                if (rand_wall[1] != 0):
                    if (maze[rand_wall[0]][rand_wall[1]-1] != "c"):
                        maze[rand_wall[0]][rand_wall[1]-1] = "w"
                    if ([rand_wall[0], rand_wall[1]-1] not in walls):
                        walls.append([rand_wall[0], rand_wall[1]-1])
                if (rand_wall[1] != width-1):
                    if (maze[rand_wall[0]][rand_wall[1]+1] != "c"):
                        maze[rand_wall[0]][rand_wall[1]+1] = "w"
                    if ([rand_wall[0], rand_wall[1]+1] not in walls):
                        walls.append([rand_wall[0], rand_wall[1]+1])

            # Delete wall
            for wall in walls:
                if (wall[0] == rand_wall[0] and wall[1] == rand_wall[1]):
                    walls.remove(wall)

            continue

    # Check the right wall
    if (rand_wall[1] != width-1):
        if (maze[rand_wall[0]][rand_wall[1]+1] == "u" and maze[rand_wall[0]][rand_wall[1]-1] == "c"):

            s_cells = surroundingCells(rand_wall)
            if (s_cells < 2):
                # Denote the new path
                maze[rand_wall[0]][rand_wall[1]] = "c"

                # Mark the new walls
                if (rand_wall[1] != width-1):
                    if (maze[rand_wall[0]][rand_wall[1]+1] != "c"):
                        maze[rand_wall[0]][rand_wall[1]+1] = "w"
                    if ([rand_wall[0], rand_wall[1]+1] not in walls):
                        walls.append([rand_wall[0], rand_wall[1]+1])
                if (rand_wall[0] != height-1):
                    if (maze[rand_wall[0]+1][rand_wall[1]] != "c"):
                        maze[rand_wall[0]+1][rand_wall[1]] = "w"
                    if ([rand_wall[0]+1, rand_wall[1]] not in walls):
                        walls.append([rand_wall[0]+1, rand_wall[1]])
                if (rand_wall[0] != 0): 
                    if (maze[rand_wall[0]-1][rand_wall[1]] != "c"):
                        maze[rand_wall[0]-1][rand_wall[1]] = "w"
                    if ([rand_wall[0]-1, rand_wall[1]] not in walls):
                        walls.append([rand_wall[0]-1, rand_wall[1]])

            # Delete wall
            for wall in walls:
                if (wall[0] == rand_wall[0] and wall[1] == rand_wall[1]):
                    walls.remove(wall)

            continue

    # Delete the wall from the list anyway
    for wall in walls:
        if (wall[0] == rand_wall[0] and wall[1] == rand_wall[1]):
            walls.remove(wall)
    
# Mark the remaining unvisited cells as walls
for y in range(height):
    for x in range(width):
        if (maze[y][x] == "u"):
            maze[y][x] = "w"

# Set entrance and exit
for x in range(width):
    if (maze[1][x] == "c"):
        maze[0][x] = "c"
        break

for x in range(width-1, 0, -1):
    if (maze[height-2][x] == "c"):
        maze[height-1][x] = "c"
        break

# Print final maze
printMaze(maze)

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