Curves from two views

Geometry
1

Rhino ( and most 3d modelling software) have a command where you can draw a 2d curve in plane and in section view and the curve in plan view adapts to the curvature in section view. In Rhino it’s called Curves from 2 views.

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In Dynamo you can achieve the same results by extruding the curves and doing a geometry intersect, but could become quite tedious. Is there a custom node that is similar to the “curves form two views” command in Rhino?

2

There isn’t a good “fail safe” solution for out of the box methodology, but you can pretty easily build something like this as a custom definition, which can be kept handy for future use.

Lofting%20Two%20Lines
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The definition is as follows:

def curvebycurves (SectionCurve,PlanCurve)
{
	SecCrv =
		Display.ByGeometryColor(
			SectionCurve,
			Color.ByARGB(
				120,255,0,0
			)
		);

	PlnCrv =
		Display.ByGeometryColor(
			PlanCurve,
			Color.ByARGB(
				120,0,0,255
			)
		);

	ExtrudeDist =
		Autodesk.Geometry.DistanceTo(
			PlanCurve.BoundingBox.MinPoint,
			SectionCurve.BoundingBox.MaxPoint
		);

	NewCurve =
		Autodesk.Geometry.Intersect(
			SectionCurve.Translate(
				SectionCurve.Normal,
				ExtrudeDist/2
			).Extrude(
				SectionCurve.Normal,
				-ExtrudeDist
			),
			PlanCurve.Translate(
				PlanCurve.Normal,
				ExtrudeDist/2
			).Extrude(
				PlanCurve.Normal,
				-ExtrudeDist
			)
		);
return = Flatten({SecCrv,PlnCrv,NewCurve});
};
2 Likes
3

We used the Curve from two views alot in Rhino. So a definition like that is very handy. Either way, it gets the job done. Thanks!!

4

Glad I could help.

Note that the nurbs aspect in my input curves will lead to some inaccuracies (as with pretty much any nurbs based work). Play around a bit and tweak the code to make it work the way that is right for you.