Working version of the Barnes-Hut NBody simulator in the Cpp repository.
Primus now uses SFML for real-time rendering of the simulation. It is built to be run from the command line, along with a number of optional flags.
A CUDA accelerated version of the program will be added eventually. Currently, cuda is a bit of a nightmare to work with across systems.
Window captures of the simulation with the GUI on. Simulation speed limited to 60 steps per second. All three examples show a solar system-like simulation, containing at least the Sun, the Earth, and a varying number of additional smaller mass (~1018 kg) particles.
Gifs were captured in real-time using Peek (github.com/peek/peek).
This project uses Boost libraries for the command line interface, and the SFML library for the drawing window. You can install these libraries with
sudo apt-get install libsfml-dev
sudo apt-get install libboost-all-dev
Clone this repository
git clone http:://github.com/nicklayden/Primus
cd Primus
Invoke the makefile
make
To run the program with default settings
./primus
| Flag | Type | Comment |
|---|---|---|
| -N | uint | Number of randomly generated particles to add to the simulation. Unbounded |
| -d (--deltat) | double | Time step between each iteration in seconds. (Deprecated. Timesteps are variable) |
| -T | uint | Total number of iterations to run the simulation for (Deprecated) |
| -t (--theta) | float | Barnes-Hut parameter theta. Controls force estimation algorithm. Setting to 0 uses the all-pairs algorithm |
| -s (--softener) | float | Softening parameter used to lower drastic effects arising from particles getting too close to each other. |
| -m (--stats) | bool | Dump simulation stats like Total Energy and Momentum and time to file. Frequency depends on -f flag |
| -f (--dumpfreq) | int | Frequency with which to record data dumps. (1/steps) |
| --fps | float | Set upper limit on framerate for the GUI. Default is unbounded. This also limits the maximum speed of the simulation |
| --draw | bool | Draw the Barnes-Hut node tree on the simulation window. Toggle on/off with the "A" key. |