Creates a freeform surface by connecting cross-sections. The method used is called interpolation, i.e. the freeform surface goes through the cross-sections.
Clicking 
opens the Surface from cross-sections pull-down menu with functions for the creation of polyhedrons.
Creates a freeform surface by interpolating a curve mesh; the resulting surface is also known as Gordon surface.
Surface from 3-D polyline frame
Derives freeform-surfaces from a polyline frame.
Clicking opens the Edges pull-down menu with functions for the placing of cross-sections on guidelines and the processing of cross-sections.
