Hi,

The Geometry.Line3d (unbounded) or Geometry.LineSegment3d (bounded) have an IntersectWith method.

So, a .NET equivalent for the inters function may be something like this:

`public Point3d[] Inters(Point3d p1, Point3d p2, Point3d p3, Point3d p4, bool onSeg)`

{

LinearEntity3d l1, l2;

if (onSeg)

{

l1 = new LineSegment3d(p1, p2);

l2 = new LineSegment3d(p3, p4);

}

else

{

l1 = new Line3d(p1, p2);

l2 = new Line3d(p3, p4);

}

return l1.IntersectWith(l2);

}