new mod: lro.gravity

[Malizma333]

Stores the initial custom gravity of a track

yGravity: float
xGravity: float

[o7Moon]

i wonder if this belongs in common. the values from a .trk can be converted into an actual gravity vector made of f64s, but it might be tricky to convert back to .trk's gravity multipliers if done that way ¹

i think for things like this where there is an initial value but it can be changed with triggers, probably it would make sense to just specify the triggers mod and even if it doesn't change over the track you just have one trigger for the initial value

Footnotes

1. its definitely possible if your gravity vector is originally from .trk multipliers to get back the same multipliers, but maybe not exactly clear how. and everything else is unlikely to work because the gravity vector has just, way more precision than the multipliers do so there is only a small chance they are representable ↩