# Naive Viable Looking N-body 2D System Generator

Delivered as a Unity package but you can also get the sources directly from github.

Made with Unity but the generation algorithm itself could be used with any engine.

### Naive

This generator is based on the idea that the center of mass of a two-body system is at a shared focus point of the two bodies.

An ellipse is made of a center, two foci and an eccentricy that is responsible for the flatness of the ellipse and the positions of the foci. An elliptical orbit means that one of the foci is actually the center of mass of the orbit. And in a two-body system, the bodies share one of their foci, which is placed at the center of mass of the system.

The naive approach I chose here is to apply this property to n-body systems, knowing that this is wrong as there is no analytical solution for n-body systems. But I think this is actually not invalid but just way too restrictive. This approach probably prevents certain configurations when n is greater than two.

### Viable looking

The system generated usually looks like it is viable but I have not yet tested the generated systems under the use of the universal law of gravitation. The planets have their own mass and their own orbit.

### N-body

This generator can be used to create a planetary system with one, two, three or more bodies.

### 2D

It is a 2D planetary system generator but adding the 3rd dimension should not be a problem I think.

### Algorithm

- Generate n bodies by randomly assigning them a mass.
- Distribute the n bodies on the screen (all bodies are at the apoapsis).
- Find the center of mass of the system formed by the n bodies.
- Generate an elliptical orbit for each body.
- Move each ellipse's center so that all foci are at the center of mass of the system.

Published | Nov 13, 2017 |

Status | In development |

Category | Tool |

Platforms | Windows, macOS, Linux, HTML5 |

Author | { Simon Chauvin } |

Tags | 2D, Generator, Gravity, Ludum Dare 40, PROCJAM |

## Download

Click download now to get access to the following files:

**NaiveViableLookingNBody2DSystemGenerator.unitypackage**16 kB

**NaiveViableLookingNBody2DSystemGenerator.zip**13 MB

**NaiveViableLookingNBodySystemGenerator (Linux).zip**16 MB

**NaiveViableLookingNBodySystemGenerator (MacOS).zip**15 MB

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