IntersectionCurveSurface Method (Curve, Surface, Double, Double)

using Rhino;
using Rhino.Geometry;
using Rhino.Geometry.Intersect;
using Rhino.Input.Custom;
using Rhino.DocObjects;
using Rhino.Commands;

namespace examples_cs
{
  public class CurveSurfaceIntersectCommand : Command
  {
    public override string EnglishName { get { return "csCurveSurfaceIntersect"; } }

    protected override Result RunCommand(RhinoDoc doc, RunMode mode)
    {
      var gs = new GetObject();
      gs.SetCommandPrompt("select brep");
      gs.GeometryFilter = ObjectType.Brep;
      gs.DisablePreSelect();
      gs.SubObjectSelect = false;
      gs.Get();
      if (gs.CommandResult() != Result.Success)
        return gs.CommandResult();
      var brep = gs.Object(0).Brep();

      var gc = new GetObject();
      gc.SetCommandPrompt("select curve");
      gc.GeometryFilter = ObjectType.Curve;
      gc.DisablePreSelect();
      gc.SubObjectSelect = false;
      gc.Get();
      if (gc.CommandResult() != Result.Success)
        return gc.CommandResult();
      var curve = gc.Object(0).Curve();

      if (brep == null || curve == null)
        return Result.Failure;

      var tolerance = doc.ModelAbsoluteTolerance;

      Point3d[] intersection_points;
      Curve[] overlap_curves;
      if (!Intersection.CurveBrep(curve, brep, tolerance, out overlap_curves, out intersection_points))
      {
        RhinoApp.WriteLine("curve brep intersection failed");
        return Result.Nothing;
      }

      foreach (var overlap_curve in overlap_curves)
        doc.Objects.AddCurve(overlap_curve);
      foreach (var intersection_point in intersection_points)
        doc.Objects.AddPoint(intersection_point);

      RhinoApp.WriteLine("{0} overlap curves, and {1} intersection points", overlap_curves.Length, intersection_points.Length);
      doc.Views.Redraw();

      return Result.Success;
    }
  }
}

Imports Rhino
Imports Rhino.Geometry
Imports Rhino.Geometry.Intersect
Imports Rhino.Input.Custom
Imports Rhino.DocObjects
Imports Rhino.Commands

Namespace examples_vb
  Public Class CurveSurfaceIntersectCommand
    Inherits Command
    Public Overrides ReadOnly Property EnglishName() As String
      Get
        Return "vbCurveSurfaceIntersect"
      End Get
    End Property

    Protected Overrides Function RunCommand(doc As RhinoDoc, mode As RunMode) As Result
      Dim gs = New GetObject()
      gs.SetCommandPrompt("select brep")
      gs.GeometryFilter = ObjectType.Brep
      gs.DisablePreSelect()
      gs.SubObjectSelect = False
      gs.Get()
      If gs.CommandResult() <> Result.Success Then
        Return gs.CommandResult()
      End If
      Dim brep = gs.[Object](0).Brep()

      Dim gc = New GetObject()
      gc.SetCommandPrompt("select curve")
      gc.GeometryFilter = ObjectType.Curve
      gc.DisablePreSelect()
      gc.SubObjectSelect = False
      gc.Get()
      If gc.CommandResult() <> Result.Success Then
        Return gc.CommandResult()
      End If
      Dim curve = gc.Object(0).Curve()

      If brep Is Nothing OrElse curve Is Nothing Then
        Return Result.Failure
      End If

      Dim tolerance = doc.ModelAbsoluteTolerance

      Dim intersectionPoints As Point3d() = Nothing
      Dim overlapCurves As Curve() = Nothing
      If Not Intersection.CurveBrep(curve, brep, tolerance, overlapCurves, intersectionPoints) Then
        RhinoApp.WriteLine("curve brep intersection failed")
        Return Result.Nothing
      End If

      For Each overlapCurve As Curve In overlapCurves
        doc.Objects.AddCurve(overlapCurve)
      Next
      For Each intersectionPoint As Point3d In intersectionPoints
        doc.Objects.AddPoint(intersectionPoint)
      Next

      RhinoApp.WriteLine("{0} overlap curves, and {1} intersection points", overlapCurves.Length, intersectionPoints.Length)
      doc.Views.Redraw()

      Return Result.Success
    End Function
  End Class
End Namespace

import rhinoscriptsyntax as rs
from scriptcontext import *
import Rhino
import System.Collections.Generic as scg
import System as s

def RunCommand():
  srfid = rs.GetObject("select surface", rs.filter.surface | rs.filter.polysurface)
  if not srfid: return

  crvid = rs.GetObject("select curve", rs.filter.curve)
  if not crvid: return

  result = rs.CurveBrepIntersect(crvid, srfid)
  if result == None:
    print "no intersection"
    return

  curves, points = result
  for curve in curves:
    doc.Objects.AddCurve(rs.coercecurve(curve))
  for point in points:
    rs.AddPoint(point)

  doc.Views.Redraw()

if __name__ == "__main__":
  RunCommand()