Create
---Purpose: Creates an empty GenHCurve2d.
- returns mutable GenHCurve2d from Adaptor2d;
+ returns GenHCurve2d from Adaptor2d;
Create(C: TheCurve)
---Purpose: Creates a GenHCurve2d from a Curve
- returns mutable GenHCurve2d from Adaptor2d;
+ returns GenHCurve2d from Adaptor2d;
Set(me: mutable; C: TheCurve)