Other Freeform Curves
Curve from FFS
Sketch > Draw > Freehand... > Curve from FFS 
You use this function to apply parameter or boundary lines of a freeform surface as a curve.
- First create a new 3-D sketch.
- After calling the function, identify the freeform surface.
- Select whether you want parameter or boundary lines to be applied. For parameter lines you also need to define whether they are to be selected in m- or n-direction.
Parameter line and boundary line (right) have been applied from the freeform surface (left)
The created curve lies exactly on the freeform surface. Select, if required,
the Representation, Active part function to
display only the new curve.
CONS from polyline
Sketch > Draw > Freehand... >CONS fom polyline 
You use this function to project a 3-D sketch edge onto a freeform surface. The result is a surface curve (CONS = Curves ON Surfaces). This is not represented optically!
