Try CreatePeriodicUniformNurbs() and CreateClampedUniformNurbs() functions on OnNurbsCurve. Those are the ones I use to create control point curves. I use RhinoInterpCurve() on RhUtil to create interpolated curves.
Creating new curves and surfaces from control points is surprisingly difficult in the Rhino SDK. I was amazed as well while researching this for Grasshopper. Luckily most of the RhinoScript methods will be available to plugin developers in Rhino5, so we'll see a new plethora of high-level functions. -- David Rutten Robert McNeel & Associates ps. Grasshopper also recognized OnPolyCurve, my previous list was incomplete. On Oct 12, 10:02 pm, ga <[EMAIL PROTECTED]> wrote: > David, > Thanks for the response. I am trying to make a nurbs curve and > hopefully being able to get/set CV's in scripted VB nodes. Have been > looking into OnNurbsCurve class for construction and CV value querying > but no luck. Any suggestions? > Thanks. > > On Oct 12, 2:18 pm, David Rutten <[EMAIL PROTECTED]> wrote: > > > Hi GA, > > > OnCurve is an abstract base class and cannot be constructed. You'll > > have to be more specific. The following types are recognized by > > Grasshopper as Curve objects: > > > OnCurve > > OnNurbsCurve > > OnPolylineCurve > > OnArcCurve > > OnLineCurve > > OnLine > > OnPolyLine > > OnArc > > OnCircle > > OnEllipse > > > I'm not too sure about OnBezier*** and OnPolynomials*** and cannot > > test this where I'm now. > > > If you need to create curves through points, either use one of the > > functions on OnNurbsCurve or in RhUtil. > > > -- > > David Rutten > > Robert McNeel & Associates > > > On Oct 12, 4:16 am, ga <[EMAIL PROTECTED]> wrote: > > > > Does anyone know how to output a nurbs curve from a VB scripted node? > > > I can't seem to find the constructor class for a simple curve. I've > > > used a polyline for the time being that works, but can't get curves > > > from the same points. > > > > The general premise for developing this node is that the standard > > > curves node seems to flatten lists going into the node thereby losing > > > their grouping and making one curve instead of say 10 dynamic curves. > > > So if we have 7 lists each a row of 10 points appended into one, > > > similar to > > > >http://groups.google.com/group/grasshopper3d/browse_thread/thread/d10... > > > > we could use the following scripted node to get 10 curves : > > > > Sub RunScript(ByVal pts As List(Of On3dPoint), ByVal num As Integer) > > > Dim spline_list As New List(Of OnPolyline) > > > > Dim bounds As Int32 = pts.Count / num > > > > 'print("bounds = {0}", bounds) > > > > For i As Int32 = 0 To bounds-1 > > > Dim spline As New OnPolyline() > > > For j As Int32 = 0 To num-1 > > > spline.Append(pts(j * bounds + i)) > > > 'print("index = {0}", j * bounds + i) > > > Next > > > spline_list.Add(spline) > > > Next > > > A = spline_list > > > End Sub > > > > Any ideas on how to construct curves here instead of polylines? > > > Thanks.
