Add the ability to do custom range mapping via Bezier spline

[franckaubry]

Add the ability to do custom range mapping via Bezier spline, resulting in a very visual way to manage data. This is a small and normal UI feature in other software, but it gives incredible control to the range mapping of data. (both single and for arrays) Sometimes (or very often, in my case) you don't want the range to go from min to max only, but via a completely custom range.

Here are some UI examples from Cinema 4D and Houdini. The two last examples gives a good idea of why this can be useful:

If one wants to make it easy for the user, a number of default spline shapes can be selected via a dropdown menu (linear, smooth, sine, ...) resulting in generating the correct curve in the spline UI.

[franckaubry]

The idea would be to change the current “Easing” drop down, into a more flexible Bézier curve. From this: To something like this:

[franckaubry]

In the Discord, this was one of the possible adaptation models: https://jordi.platinum.edu.pl/xsplines/