A user-friendly guide to the Genesis Device
The Genesis Device is an advanced mod for Planetary Annihilation system designing. The main section of the mod allows you to build more accurate ellipses in the Planetary Annihilation System Designer by enabling the use of the Polar Coordinate System instead of the old X&Y Cartesian Coordinate System.
When the mod is successfully installed and activated, a new “Ellipse Generator” tab should appear when selecting any planet in the System Designer. You can find the Genesis Device mod on the PA Mod Manager.
There are five parameters — four mandatory and one optional — that will be used as input:
- Perihelion: The minimum distance from the sun/planet in the ellipse. Currently, the minimum distance to the sun is 12,500 (This value can be greater depending on the planet’s mass and planet’s radius).
- Aphelion: The maximum distance from the sun/planet in the ellipse. Currently, the game limits the maximum distance to 200,000 from the sun.
- Ellipse Axis Tilt: This is the angle you tilt the ellipse’s major axis with respect to the horizontal line, in the counter-clockwise direction.
- Starting Angle: This is the polar angle at which your planet starts with respect to a Polar Coordinates System, where for zero degree the planet is at the aphelion, and for 180 degrees, the planet is at the perihelion.
- Orbital Direction (optional): Changes the orbit’s direction to either clockwise or counter-clockwise.
After inserting the desired values, click “Calculate Orbit” and the planet will be set in a position that is coherent to the given values.
Using the Mod
The first examples will use the Sun as the center of the orbit, so, for these cases, do not change the “Orbiting Body” drop-down box.
By changing the Perihelion and keeping all the other parameters fixed, the minimum distance to the sun will behave like this:
By changing the Aphelion and keeping all the other parameters fixed, the maximum distance to the sun will behave like this:
By changing the Ellipse Axis Tilt and keeping all the other parameters fixed, the position of the Ellipse will behave like this:
By changing the Starting Angle and keeping all the other parameters fixed, the planet will “move” within the ellipse, as can be seen below:
Orbiting Another Planet
In order to make a moon to orbit another planet using the mod, first one must click and drag it to orbit the desired planet, then swap to “Ellipse Generator” tab. In the “Orbiting Body” box, select the corresponding planet your desired moon is orbiting, then insert the desired parameters described above and click “Calculate Orbit”. This extra step is due to a bug in the Planetary Annihilation System Designer that requires planets to be “snapped” into orbit through clicking and dragging even when the input numbers are entered correctly.
For elliptical orbits, setting two or more planets within the same Ellipse and changing only the Starting Angle may result in incidental planet collision. The distance between the planets will be minimal when they are very close to the Aphelion.
Try it yourself
After some good practice, one can produce the following artwork:
About The Math
For further reference about the physics equations regarding this mod, please refer to this short paper.