Skins are sets of Sides. A Skin can be open or closed.

skin = skinset.add( Skin(number, [side1, side2, side3, ...]) )

where

• Skin can be replaced by MultiProjSkin (derived class). MultiProjWire can handle multiple projections when the normal is not continuous
• The function skinset.add can take up to ten Skins in argument. If only one is supplied, the function add returns a reference pointing towards this skin. If more than one are supplied, no reference is returned.
• If the Skin is to be meshed by the transfinite mesher 3D Meshers (Volumes)), the order of the faces that define it matters.