What is the method rhino uses to create an interpolated curve? After reading a bit about Bezier curves etc I had thought it was something similar to what is described in section 20 & 21 here. However if I create an interpolated curve (black) from some set points (green), then turn on the edit points, two additional points appear, one just after the start point and one just before the end point. How are these points created?
For some background: I have some custom production software that allows a user to generate and edit a curve to create a desired shape over an image. It is more intuitive for the user to create this curve using a method like interpolate points where the curve lies on the created points rather than a b-spline. I would like to recreate this curve as accurately as possible into rhino using these created points. I can change the method the software uses to generate the curve but I would like this to produce the same curve that rhino does.
Unfortunately using rhino itself to generate these original curves is not an option.