Mazes for Programmers in Rust

This repository contains code following the outline algorithms in Mazes for Programmers by Jamis Buck, which can be found here.

mazesfp is a library containing maze construction algorithms which can be applied to a grid struct.

Algorithms

For all these approaches a grid of squares is constructed. In this context the term 'wall' refers to the boundary between two cells within the grid.

Binary Tree

In the binary tree algorithm each cell of the grid is visited and a coin is tossed, the result determines if either the northern or eastern wall is erased (where possible). This is the simplest algorithm, although not the best in terms of results.

Run the example with:

cargo run --example binary_tree

Sidewinder

In the sidewinder algorithm a coin is again tossed, however if the result is heads, the eastern wall is erased and the cell is added to a list of visited cells. If the result is tails, a random cell from those visited is chosen and the southern boundary is erased, the visited cell list is then cleared. If the cell is an eastern boundary cell it is treated as tails.

Run the example with:

cargo run --example sidewinder

Aldous-Broder

In the Aldous-Broder algorithm developed by David Aldous and Andrei Broder is a random walk algorithm. A cell is chosen at random and a neighbour then selected also at random, if the neighbour has not yet been visited a path is cut between them.

Run the example with:

cargo run --example aldous_broder

Wilson

Wilson's algoritm developed by David Bruce Wilson consists of firstly randomly setting a cell as visited, then randomly selecting another cell as a start cell. A random walk is performed until a visited cell is reached, if a path leads to a loop this loop is erased and the process continues from the point prior to it.

Run the example with:

cargo run --example wilson

Hunt and Kill

With the Hunt and Kill algorithm a random walk is performed, however unlike Aldous-Broder cells cannot be re-visited, a pathway can only be made through unvisited cells. A random walk is performed until a loop occurs, when this happens starting from the top of the maze the first cell unvisited cell with at least one visited neighbour is set as the new continuation point (after a path is cut between itself and the visited cell).

Run the example with:

cargo run --example hunt_and_kill

Reverse Backtracker

The reverse backtracker algorithm is similar to Hunt and Kill in terms of initial motion, however rather than finding the first unvisited cell starting from the top row instead we backtrack along the current path to the first cell which has a neighbour which has not been visited and head that direction.

Run the example with:

cargo run --example reverse_backtracker