Braise

Probabilistic cellular automaton for fire propagation with real-time OpenGL visualization.

Description

Braise is a visual fire propagation simulation based on a probabilistic cellular automaton. The initial grid can start with a 5x5 square of burning cells in the center, or with a fire front from one of the four cardinal directions (east, west, north, south). The fire spreads according to probabilistic rules.

Simulation Rules

1. A burning cell (yellow) becomes burnt (black) in the next generation
2. A green cell ignites with probability p if at least one neighbor is burning
3. A burnt cell remains burnt

Cell States

• Green (0): Unburnt cell
• Yellow (1): Burning cell
• Black (2): Burnt cell

Installation

Dependencies

sudo apt install g++ libgl1-mesa-dev libglu1-mesa-dev freeglut3-dev libx11-dev libfmt-dev libspdlog-dev

Build

make

Usage

The simulation requires three mandatory parameters and one optional parameter:

./build/braise <height> <width> <probability> [front]

Parameters:

• height: Number of rows in the grid (integer)
• width: Number of columns in the grid (integer)
• probability: Ignition probability (float between 0.0 and 1.0)
• front (optional): Fire front starting position
  • east: Fire starts from the eastern edge (right side)
  • west: Fire starts from the western edge (left side)
  • north: Fire starts from the northern edge (top)
  • south: Fire starts from the southern edge (bottom)
  • If not specified, fire starts in a 5x5 square in the center

Examples:

# Default: 5x5 square in the center
./build/braise 100 100 0.5

# Fire starting from the eastern edge
./build/braise 100 100 0.5 east

# Fire starting from the northern edge
./build/braise 100 100 0.5 north

Or using the Makefile (uses default parameters):

make run

Project Structure

braise/
├── include/
│   └── fire.hpp          # Simulation function declarations
├── src/
│   ├── fire.cpp          # Cellular automaton logic
│   │                     # - generation(): computes next generation
│   │                     # - neighbors(): counts burning neighbors
│   └── main.cpp          # OpenGL interface and render loop
├── Makefile              # Build script
└── README.md

Technical Details

• Rendering engine: OpenGL with GLUT (double buffering)
• Update frequency: 50ms per generation
• Random generator: Mersenne Twister (std::mt19937)
• Neighborhood: 8 neighbors (Moore neighborhood)
• Logging: spdlog for debugging

License

Apache License 2.0