Path Finder Visualizer

An interactive maze for exploring breadth-first search. Place a start, an end, and walls, then watch the search visit cells and reveal a shortest route.

Originally a 2019–2020 Python/Tkinter/Pygame project. This refresh keeps the maze idea and replaces the search and interface with a small Tkinter application and an independently testable search module.

Try it

Use Python 3.10 or newer with Tkinter. No third-party Python packages are required. Check Tkinter with python3 -m tkinter; if that fails, use a Python installation that includes Tk.

python3 "Visual Maze.py"

1. Select Wall, then click cells to add or remove obstacles.
2. Select Start or End and click a cell to move that marker.
3. Choose Find path. Blue cells show exploration; gold cells show the route.
4. Edit the maze or choose Clear walls to explore another layout.

The interface uses a 12×12 grid. The search module accepts any positive rectangular dimensions, with coordinates (x, y) measured from the top left. Moves are up, down, left, or right, with equal cost. This is an unweighted-grid visualizer, not a weighted routing engine.

How it works

pathfinding.py uses a FIFO queue, records each cell once, and reconstructs the route through parent pointers. It returns a SearchResult with the route and exploration order. An unreachable target returns path=None; malformed coordinates and blocked endpoints raise ValueError.

from pathfinding import shortest_path

result = shortest_path(5, 4, (0, 0), (4, 3), walls={(2, 0), (2, 1)})
print(result.path)

Search time and memory are O(width × height) in the worst case. Animation uses Tk callbacks so the interface can respond while exploration is displayed.

Verify

python3 -m unittest discover -v

Tests cover detours, unreachable targets, coincident endpoints, invalid coordinates, and every wall configuration on a 3×3 grid, checked against an independent distance-relaxation implementation.

Repository guide

• pathfinding.py — search and validation; usable without a display.
• Visual Maze.py — interactive editor and animation.
• test_pathfinding.py — algorithm tests.

The original image assets remain in the repository for historical context; the refreshed interface does not depend on them. Earlier implementations remain in git history.