> What is the exact name of the curves that is used in Moi :"Through point?"

The method for creating that type of curve is usually called an "interpolated curve". One good reference for this is The NURBS Book, Les Piegl & Wayne Tiller, Springer-Verlag 1995–1997.

You may be able to find something online about "NURBS interpolation".


> Nurbs yes but what about the tangent ?
> or the degre of tension (streching) between 1 point between 2 points?

The version MoI uses creates a tangent automatically. You can edit it later by turning on control points and moving the second-to-last point around.

The tension is actually updated for the next beta release, it will use a type called "centripetal knot spacing".


But the "Through point" method is not really the best way to create a curve for the method that you are thinking, though - because it forces the curve to go exactly through every point, it tends to create wiggles in the curve when you have many points. For creating a curve through many points there is a different process called "fitting" which creates a curve that is guided by the points (to a certain tolerance) but is not forced to go exactly through them. That is usually a better way to get a smooth curve. MoI doesn't expose a way to do this right now, but Rhino does with the FitCrv command.

- Michael