JavaFX Algorithm Visualizer

Repository

For running this project and documentation, visit the GitHub repo: javafx-algorithm-visualiser

Demo Video

If the embedded video doesn’t load, you can watch the demo directly on YouTube

Overview

An interactive graph algorithm visualiser to help users better understand how algorithms work. At the time of writing this the repo currently only supports Dijkstras algorithm but I plan on extending this to other graph based algorithms.

What I Built

I developed an interactive algorithm visualisation tool mainly for graph based algorithms which involves a visual representation of nodes and weighted directed edges. The application also has a step button to allow you to step throgh and algorithm and see what happens at each stage. There is also a table showing visited and distance to different nodes which is updated in real-time. The App also uses a modular architecture with clear seperation between algorithm logic, data models, UI, and utility functions making it easier to build on top of this code base.

Technologies Used

• Java+: Core programming language with modern language features
• JavaFX: Package for building GUIs
• Gradle: Build automation and dependency management
• Object-Oriented Design: Clean architecture with interfaces, inheritance, and encapsulation
• Data Structures: Custom implementations of graphs, priority queues, and algorithm state management

Key Features

• Algorithm Visualisation: Currently only supports Dijkstra’s shortest path algorithm
• Interactive Controls: Step button to manually step through algorithm iterations
• Visual Feedback: Color-coded nodes based on which node we are visiting and processing
• Extensible Design: Algorithm interface allows easy addition of new graph-based algorithms

What I Learned

• Algorithm Implementation: Deepened understanding of graph algorithms by implementing them from scratch
• JavaFX: Improved skills with building Java GUIs, UI controls, event handling, and custom data structure implementation
• Software Architecture: Practiced separation of concerns with distinct packages for algorithms, models, UI, and utilities
• State Management: Learned to translate algorithm states into visual representations effectively
• Cross-Platform Development: Implemented build systems that work consistently across different operating systems
• Problem Solving: Overcame challenges in geometry for edge rendering and arrow head positioning (this was probably one of the most confusing parts of the project)