[in] Input polyline fit points of which are interpolated by the curve.
isPeriodic
[in] true if and only if the curve is periodic.
Remarks
Constructs a 3D spline by a degree and fit points provided by a polyline. If isPeriodic is true then the first and the last fitPoints from fitPolyLine must be identical.
High degree values make curve more flexible. For example degree 1 is used to define a segment, degree 2 is used to define a nurb circle, etc.