Vector3Decimal

Stores a 3D vector as decimal values. Created for usage with Unity. Non-unity Vector3Decimal coming soon.

Why? A float can only store 7 digits of precision and Vector3 uses float, limiting the precision of the vector at high magnitudes. To demonstrate:

If my minimum requirement for precision is 0.001 meters, then I can’t store numbers with values more than 7 decimal places away:

NumA is Valid: 6358.331 This number is precise to the 3rd decimal point, or in this case, it's precise to the tenth of a millimeter.

NumB is Invalid: 10223.99 This number is precise to the 2nd decimal point: not precise enough.

Notice that each of those numbers only contains 7 digits, the limit for a float. If you were to add just ~400 to the NumA, the decimal point would move one place to the left, making it invalid and only precise to the 2nd decimal point.

A decimal has 28-29 digits of precision. That’s a lot! To compare the precision of a float and a decimal, here’s some analogies.

A float can store distances of a few kilometers with precision to the millimeter.

A decimal can store distances of many SEXTILLIONS of kilometers, while maintaining precision to the millimeter.

float: XXXX.XXX

decimal: XXX,XXX,XXX,XXX,XXX,XXX,XXX,XXX.XXX

This amount of precision will allow me to simulate a unimaginably larger space.

Documentation

...	...
`up`	`new Vector3Decimal(0, 1, 0)`
`right`	`new Vector3Decimal(1, 0, 0)`
`forward`	`new Vector3Decimal(0, 0, 1)`
`zero`	`new Vector3Decimal(0, 0, 0)`
`ToVector3f()`	`Vector3` from `this`.
`Distance(Vector3Decimal a, Vector3Decimal b)`	Distance from `a` to `b`.
`Dot()`	Returns the dot product as a `decimal`.
`Cross(Vector3Decimal a, Vector3Decimal b)`	Cross product of `a` and `b` as a `Vector3Decimal`
`ToString()`	String representation of `this`.

This class is dependent on DecimalMath by nathanpjones.

I have made this struct nearly completely interchangeable with the Vector3 type. Here’s an example:

void UnloadBody(Body bod)
{
   Vector3Decimal pos = _obs_body._global_position + bod.transform.position; // position from reference frame position + difference
   
   bod._global_position = pos;
   
   Vector3Decimal vel =  _obs_body._global_velocity + bod.physics_properties.velocity; // velocity from reference frame position + difference
   
   bod._global_velocity = vel;
   
   _loaded_bodies.Remove(bod);
   
   bod.gameObject.SetActive(false);
   
}

This is an Unload() function I wrote for Stardeep. physics_properties.velocity and transform.postion are both Vector3s, but as you can see, I do arithmetic without needing to case the Vector3s.

mecha-moonboy/Vector3Decimal

Vector3Decimal