Applying Centrifugal Force to Controller

[_Aka_]

Just to confirm:
If my volume was a doughnut made of 4 control points, which has a skinny cross at the start and really fat cross half way around.
A pathF value of 0 or 1 would give the smallest value, while a pathF value of 0.5 would be the highest value?

Yes

If then, I were to select the control point at 0.25 and drag it extremely far away so that the first half of the loop is a much longer distance; would a pathF value of 0.5 still return the point exactly on the middle control point or would it now be located somewhere on the path 50% of the length?

In the contexte of CG data (i.e CGData class and its subclasses, all used in Curvy Generator), which CGVolume is part of, a pathF of 0.5 means a point at half the total distance.
This is not to be confused with TF in the context of a spline (i.e CurvySpline class), where 0.5 means the middle control point, whatever the length of the segments are. More about the spline case here: https://curvyeditor.com/documentation/splines/start

EDIT: going back to my first question, how do I get from the volumeController to the spline so I can call gettangeant on it? I thought it would be under volumedata..

You can't get a spline from a CGVolume. But the CGVolume has the needed data in it
VolumeController.VolumeData.InterpolateDirection(pathF)


To try to explain you more the difference in Curvy between a spline (CurvySpline) and a path (CGPath), the first is a set of mathematical equations defining an infinite number of points, that are sampled when needed, while a path is the result of the spline's sampling, i.e a finite set of points on that spline.