Python Pathfinding Visualizer

Required Installations

 python3 -m pip install pygame==2.1.2

Usage

Start the application:

 python PathfindingVisualizer.py

Introduction

This is a visualization tool for pathfinding algorithms.

Currently there are 2 algorithms implemented for visualization (more will be added in the future):

• Breadth-first search
• Depth-first search

The visualization consists of nodes and connections between them (paths). Each node and each connection can be manually added or removed. To get startet you can follow the short tutorial below:

1. Create nodes on the canvas (by clicking left mouse button) --> each node created is provided with a unique label (single character)
2. Select your created nodes (by clicking on existing node) and connect (key 'c') them --> be aware, that all selected nodes are connected with each other!
3. If needed, remove nodes (by placing mouse cursor on node and pressing key 'r') or disconnect them (by selecting nodes and pressing key 'd')
4. Choose a start node (by putting mouse on node and pressing key 's') and a target/end node (by putting mouse on node and pressing key 'e')
5. Run pathfinding algorithm visualization (key '1' for BreadthFirstSearch, key '2' for DepthFirstSearch) --> be aware that to you need to specify a start and end node to start the pathfinding (However, they do not need to be connected)
6. Stop/Reset the pathfinding algorithm progress (key 'SPACE')

A summary of the possible actions, as well as a legend for the meaning of colors and symbols can be found in the next two sections.

Controls

Action	Controls
Create node	Mouse_left_click on free space
Remove node	Position mouse cursor on existing node + key 'r'
Select node	Mouse_left_click on existing (unselected) node
Unselect node	Mouse_left_click on existing (selected) node
Mark start node	Position mouse cursor on existing node + key 's'
Mark end node	Position mouse cursor on existing node + key 'e'
Connect nodes	key 'c' (connects all selected nodes)
Disconnect nodes	key 'd' (disconnects all unselected nodes)
Start breadth-first visualization	key '1'
Start depth-first visualization	key '2'
Stop/Reset algorithm progress	key 'SPACE'

Legend

Symbol/ Color	State
	Default node
	Selected node
	Start node
	End/Target node
	Waiting (Node is on the algorithms "waitlist" to be viewed soon)
	Focused (Node is currently focused by the algorithm)
	Already visited (Node was already visited by the algorithm)
	Final node (Node is part of the final path proposed by the algorithm)

Note: same colors also apply to the connections