B-spline Approximation (CAD - Curves - S BSpline < Points ...)

B-spline curve going trough input points with definition of
 the way-in and way-out-direction.

The first and the second point define the way-in-direction.
The second last and the last point define the way-out-direction.
The curve goes through point-1, point-3, the following points,
  but not through the second last point.




Functions:
  UT3D_bspl_l2appr