OpenNurbs model

i have builded a .3dm model by extrusing a curve ,but i cannot find its control vertexs in my OpenNurbs program . so can u give me some advervis?

by the way , the ON_ArcCurve’s center is (0,0,0) when i builded it ,but Opennurbs shows the Center is (-10,0,0),do u know why?thank u. :grinning:

Hi @user230,

A control point (or vertex) is a property of a NURBS curve or surface. I can see, from your dump above, that you don’t have either of those. That is, an ON_Extrusion does not have control points.

If you, for some reason, need control points from the extrusion, you can create a NURBS curves from using ON_Extrusion::GetNurbForm.

— Dale