All Case Studies

2D A* Pathfinding System

February, 2024

This 2D A* pathfinding system in Unity features grid-based visualization, animated path rendering, and dynamic obstacle handling, and tile costs. The project demonstrates real-time pathfinding logic with adjustable parameters, offering a practical and visual approach to understanding the algorithm.

Screenshot showcasing the A pathfinding algorithm in Unity, featuring a grid-based maze with a highlighted red path from a green starting point to a target destination, demonstrating real-time shortest-path calculation
Visualization of A* pathfinding algorithm tracing the shortest path in a grid maze with red and green tiles highlighting the start and end points.
Demonstration of A* algorithm's pathfinding logic in a black-and-white grid maze with a red-highlighted optimal path.
Interactive A* pathfinding grid simulation with dynamically updated red path connecting the green start tile to the red destination.

Introduction

  • Overview: This project demonstrates a basic 2D implementation of the A* pathfinding algorithm, visualized with a grid-based UI in Unity.
  • Motivation: My goal was to gain a deeper understanding of the A* algorithm by implementing it in a system that could visualize its real-time behavior in response to different parameters. This approach allowed me to explore the algorithm from both a coding perspective and a conceptual one, observing how it adapts and responds to various conditions.

Key Features

  • A* Pathfinding Algorithm: The system calculates the shortest path between two points while avoiding obstacles. It evaluates possible paths, factoring in movement costs to choose the most efficient route.
  • Grid-Based UI: The algorithm operates on a grid where tiles are marked as walkable or non-walkable, with each tile potentially having a unique movement cost.
  • Animated Path Visualization: The path is animated by drawing one path point at a time.
  • Real-Time Adaptability: The system continuously evaluates changes in the grid, updating paths based on tile states and costs.

Key Challenges & Solutions

1. Writing the A* Algorithm in C#

  • Challenge: Translating A* pseudo-code into Unity C# required a deep understanding of its flow, variables, and logic to ensure accurate pathfinding.
  • Solution: Broke down the A* algorithm into logical steps and implemented it iteratively, using debugging to verify correct path calculations at each stage. This method ensured a robust, bug-free system capable of dynamically responding to grid changes.

2. Path Visualization

  • Challenge: Creating dynamic, animated path visualization.
  • Solution: Used Unity’s LineRenderer with a coroutine to animate the path-drawing process, iteratively rendering the path one vector point at a time for a step-by-step effect.

Future Development

Potential enhancements include:

  • 3D Adaptation: Expanding this implementation to handle 3D environments.
  • Advanced Obstacles: Adding features like moving obstacles or other external variables affecting the pathfinding logic.
  • Improved UI: Further refining the grid UI for better visual clarity and aesthetics.

Key Takeaways

Although simple in appearance, this project provided deep insights into A* pathfinding, particularly the logic and structure behind it, as I studied and translated pseudo-algorithms into Unity C#. Building a custom grid system and visualizing the algorithm’s progress with adjustable parameters gave me hands-on experience with the its practical application and adaptability.

Have a Unity Project in Mind?

Let’s chat about how I can help making it happen.

I’ll get back to you the next business day.

Get in Touch