Are there any methods for extracting parameters of polysurface or solid?

rhinoscript
rhino5

#1

Hello all!
I need parameters like Knots vector, control point, weight… of polysurface or solid.
I made the script that extracting paramters of surface. but I can’t extract parameters of polysurface.
So i need your help.
are there any methods for extracting parameters of polysurface or solid? or not?
I appreciate your interest. Thank you!


(Dale Fugier) #2

Polysurfaces, or Breps, do not have parameters like knots vectors, control points, weights, etc. Rather, the underlying surfaces of Brep faces have these parameters.

http://developer.rhino3d.com/guides/cpp/brep-data-structure/

Neither RhinoScript nor the rhinoscriptsyntax namespace in Rhino.Python give you access to this, unless the Brep has a single face. If you have Brep with multiple faces (e.g.a polysurface), then you can access these parameters an more using RhinoCommon.

Here is a Python sample worth studying:

https://github.com/dalefugier/SamplePy/blob/master/SampleTraverseBrepFace.py

Looking at the sample on line 32, this is where the underlying surface of a Brep face is obtained. Having the surface, you can now query it for parameters such as domain, knots, etc.

http://developer.rhino3d.com/api/RhinoCommonWin/html/T_Rhino_Geometry_Surface.htm

– Dale