NBody Raylib

An n-body simulation made with Raylib and C.
This projects takes a JSON file as an input and runs a real time n-body simulation with visual rendering.
JSON files are loaded with cJSON.

Building

1. Install Raylib on your system
2. Clone this repository
3. Compile with make

Trying some examples

You can find some examples on the examples/ directory.
Run them with ./BodySim <example.json>

Creating Custom Simulations

Create a custom simulation by writing a JSON file.

Parameter	Unit	Description
scale	Un/AU	Game units per Astronomical Unit (AU)
name	-	The bodies name
color	RGB	Visual color (0-255 values)
mass	kg	Body mass
radius	pixels	Displayed size
position.x/y	AU	Initial position (fraction of AU)
velocity.x/y	km/s	Initial velocity

Example:

{
  "scale": 250000,
  "bodies": [
    {
      "name": "Alpha",
      "color": { "r": 255, "g": 100, "b": 100 },
      "mass": 4e25,
      "radius": 100,
      "position": { "x": -0.04, "y": 0.00 },
      "velocity": { "x": 0.00, "y": 0.25 }
    },
    {
      "name": "Beta",
      "color": { "r": 100, "g": 255, "b": 100 },
      "mass": 4e25,
      "radius": 100,
      "position": { "x": 0.04, "y": 0.00 },
      "velocity": { "x": 0.00, "y": -0.20 }
    }
  ]
}

Run your custom simulation with:

./BodySim path/to/your_sim.json

Simulation Controls

The following keyboard controls are available during simulation:

Key	Action
F11	Toggle fullscreen mode
→	Increase simulation speed
←	Decrease simulation speed
T	Toggle trajectories
D	Toggle debug information
N	Toggle body names