Reaction-Diffusion Simulation

This project implements a Reaction-Diffusion simulation using the Gray-Scott model, available in both C and web versions. It visualizes various patterns that emerge from the interaction of two virtual chemicals in a 2D grid.

Visual Demonstrations

Mitosis (Animated)	Mitosis (Static)	Coral Growth (Animated)
Coral Pattern (Static)	Spiral Pattern 1	Spiral Pattern 2

Table of Contents

• Introduction
• Features
• Versions
  • C Version
  • Web Version
• Mathematical Model
• Getting Started
  • Prerequisites
  • Installation
• Usage
  • Running the Simulation
  • Controls
  • Changing Patterns
• Project Structure
• Building and Running
• Contributing
• Possible Improvements
• FAQ
• References
• License

Introduction

Reaction-Diffusion systems are mathematical models that describe how the concentration of substances changes in space over time due to local chemical reactions and diffusion. These systems can produce a wide variety of patterns, including spots, stripes, and more complex structures, making them useful for modeling various biological and chemical phenomena.

Features

• Real-time simulation of the Reaction-Diffusion process
• Multiple pre-defined patterns (see Changing Patterns)
• Interactive controls (see Controls)
• Cross-platform support (C and Web versions)
• Easy-to-use build system

Versions

C Version

The C version provides a decent-performance simulation using the Raylib graphics library. It offers:

• Decently fast, real-time rendering
• Platform-native window and controls
• Easy compilation and execution via batch file

Jump to C installation instructions

Web Version

The web version allows for easy access and sharing of the simulation. Features include:

• Browser-based simulation (no installation required)
• Interactive UI for pattern selection and parameter adjustment
• Responsive design for various screen sizes

Try the web version now

Mathematical Model

This simulation uses the Gray-Scott model, defined by the following partial differential equations:

∂A/∂t = D_A ∇²A - AB² + f(1-A)
∂B/∂t = D_B ∇²B + AB² - (k+f)B

Where:

• A and B are the concentrations of two chemicals
• D_A and D_B are the diffusion rates of A and B
• f is the feed rate
• k is the kill rate
• ∇² is the Laplace operator

Getting Started

Prerequisites

• For C version:
  • C compiler
  • Raylib graphics library
• For Web version:
  • Modern web browser with JavaScript enabled

Installation

1. Clone the repository:

   git clone https://github.com/datavorous/Gray-Scott-Reaction-Diffusion-Model.git
   

2. For C version, install Raylib following the instructions on their website.

3. The web version requires no additional installation.

Usage

Running the Simulation

C Version

Navigate and run the build.bat file, after placing the libraylib.a file inside the lib/ folder. This will compile and run the simulation.

Web Version

Open the index.html file in your web browser, or visit the online demo.

Controls

• Left-click: Add chemical B to the simulation
• Spacebar: Pause/unpause the simulation
• Enter key: Reset the grid

Changing Patterns

To change patterns in the C version, modify the f and k values in the main.cpp file according to this table:

Pattern	f	k
Mitosis	0.0367	0.0649
Coral Growth	0.0545	0.062
Fingerprint	0.055	0.062
... (and so on)

In the web version, use the dropdown menu to select different patterns.

Project Structure

reaction-diffusion-simulation/
├── bin/
│   └── Makefile
├── include/
├── lib/
├── src/
│   └── main.cpp
├── build.bat
├── index.html
└── README.md

Building and Running

1. Navigate to the bin folder
2. Double-click build.bat or run it from the command line
3. The script will compile the code and launch the simulation

Contributing

We welcome contributions to the Reaction-Diffusion Simulation project! Here's how you can help:

Quick Start

1. Fork the repo and create your branch from main.
2. Make your changes, adhering to the best practises.
3. Ensure your code passes all tests.
4. Submit a pull request.

Reporting Issues

• Check existing issues before creating a new one.
• Provide detailed information: version, OS, steps to reproduce, expected vs. actual behavior.

Coding Standards

• Use the accepted and standard procedure for a given language.
• Use 4 spaces for indentation.
• Write clear, well-commented code.

Commit Messages

Follow the Conventional Commits specification:

type(scope): brief description

Longer description if necessary

Closes #123

Testing

• Write unit tests for new features or bug fixes.
• Ensure all tests pass before submitting a PR.

Documentation

• Update README.md and comments for significant changes.

Possible Improvements

1. Implement real-time parameter adjustment in C version
2. Add option to switch between different models
3. More liquids?
4. Optimize for larger grids using GPU acceleration
5. Implement more complex reaction-diffusion systems

FAQ

Q: Why does the simulation slow down with larger grids? A: The computational complexity increases with grid size. Consider lowering the resolution or using a more powerful machine.

References

1. Pearson, J. E. (1993). Complex Patterns in a Simple System. Science, 261(5118), 189-192.
2. Turing, A. M. (1952). The Chemical Basis of Morphogenesis. Philosophical Transactions of the Royal Society B, 237(641), 37-72.

License

This project is licensed under the GNU General Public License v3.0 - see the LICENSE file for details.

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Note: This project is for educational purposes only. It does not claim to accurately represent real-world chemical or biological processes.