Extracting objects from CurveIntersections type within nested loops

Grasshopper Developer
,
1

I can´t reference the CurveIntersection object to extract results working with nested loops.
Getting the error “Object reference not set to an instance of an object”. Easily achieved with a single CurveIntersection but many tries and no luck. Help is highly appreciated! Thanks…

curvesXplane.gh (131.3 KB)

2

Hi,

Is this what you need ?

private void RunScript(List<Plane> planes, DataTree<Curve> curves, ref object A, ref object B)
  {

    DataTree<Rhino.Geometry.Intersect.CurveIntersections> dtInters = new DataTree<Rhino.Geometry.Intersect.CurveIntersections> ();
    DataTree<Point3d> pts = new DataTree<Point3d>();

    for (int i = 0; i < curves.BranchCount; i++)
    {
      for (int j = 0; j < curves.Branch(i).Count; j++)
      {
        Curve c = curves.Branch(i)[j];
        Plane p = planes[i];
        Rhino.Geometry.Intersect.CurveIntersections intersections = Rhino.Geometry.Intersect.Intersection.CurvePlane(c, p, 0.001);
        dtInters.Add(intersections, new GH_Path(i, 0));

        if (intersections != null)
        {
          IEnumerator ie = intersections.GetEnumerator();

          while (ie.MoveNext())
          {
            Rhino.Geometry.Intersect.IntersectionEvent iev = ie.Current as Rhino.Geometry.Intersect.IntersectionEvent;
            pts.Add(iev.PointA, new GH_Path(i, j));

          }
        }
    }

    A = pts;
    B = dtInters;

  }

Do you really need the C# for this ? Component does just fine.

curvesXplane.gh (141.0 KB)

image
image860×441 43.8 KB

1 Like
3

Thank you very much mr @magicteddy. It works.

I¨m working with c# component because GH components are very spread all over my screen in a messy way and I have many variables to manage, so I´d like to keep the script inside the custom c# component and using GH components for main variables and things like custom previews, graph mappers, curvature analysis, kangaroo and others. I¨m modeling a little roof.

Without your help staying within c# could be impossible as you showed me things out from my understanding, specially the last lines of the code. tx again.

I would like to know if there is a simpler way to achieve this… or… understanding better what you wrote. Seems I have some readings pending.

4

How do you show the title text of the component´s name?

5

That is Sunglasses plugin - a must have.

Due to the use of IEnumerator the CurveIntersections class is not that easy to implement, I’m afraid the above is the simplest you can do…

Or not ? After reading this :

I forgot one can use foreach to loop through an IEnumerator<T>.

 private void RunScript(List<Plane> planes, DataTree<Curve> curves, ref object A, ref object B)
  {

    DataTree<Rhino.Geometry.Intersect.CurveIntersections> dtInters = new DataTree<Rhino.Geometry.Intersect.CurveIntersections> ();
    DataTree<Point3d> pts = new DataTree<Point3d>();

    for (int i = 0; i < curves.BranchCount; i++)
    {
      for (int j = 0; j < curves.Branch(i).Count; j++)
      {
        Curve c = curves.Branch(i)[j];
        Plane p = planes[i];
        Rhino.Geometry.Intersect.CurveIntersections intersections = Rhino.Geometry.Intersect.Intersection.CurvePlane(c, p, 0.001);
        dtInters.Add(intersections, new GH_Path(i, 0));

        if (intersections != null)
        {
          foreach (Rhino.Geometry.Intersect.IntersectionEvent iev in intersections)
          {
            pts.Add(iev.PointA, new GH_Path(i, j));
          }
        }

      }

      A = pts;
      B = dtInters;
    }
  }
1 Like