Vesta - Large-Scale Fire Simulator
Vesta is a program to run large-scale, cell-based, wildfire simulations. It was developed within the Fire Paradox project. Vesta also was the goddess of the hearth, home, and family in Roman religion. Vesta is free software and is released under the GNU GPL v3.
Design
Vesta is a cell-based simulator. This was chosen over the vector-based approach for many reasons:
- performance: cell-based spread algorithms generally use less processing power to achieve results comparable to vector-based algorithms. They can also easily be scaled to use multiple processors, which is important to exploit the multi-core architectures that modern machines are built on.
- robustness: vector-based algorithms have many implementation details that are hard to solve, such as handling self intersections, union of isolated regions, etc. Not resolving these issues correctly can lead to unstable simulations and incorrect results. It is generally far easier to develop robust and correct cell-based algorithms.
Vesta separates the problem of simulating fires in two independent modules:
- fire model - responsible for computing the fire velocity at any point of the simulation domain, depending on conditions such as terrain slope, wind speed and direction, vegetation, etc.; and
- fire spread engine - determines how the fire spreads the fire from cell to cell. It queries the fire model to determine how fast the fire must spread.