Points Not Following NURBS Curve – Missing List.Rider in Dynamo 2025 (Clockwork 3.3)

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Hi guys, I’m currently working in Dynamo 2025 and practicing the Select Model Element node to pick a NURBS line. The selection works, but the issue is with the generated points — they are not following the base line correctly. As shown in the screenshot, the points extend beyond the selected curve, instead of staying on it.

In addition, I need to use the List.Rider node for parts. However, I’ve installed Clockwork 3.3, and this node doesn’t appear to be available in this version.
Can you advise:

  1. How to correct the points so they stay strictly on the base NURBS line?

  2. What is the best alternative if List.Rider is missing or unavailable in Clockwork 3.3?

Appreciate your guidance on a working workaround or design script for this issue.

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Never heard of List.Rider.

But it’s likely that you meant to use a range of parameters from 0 (the start of the curve) to 1 (the end of the curve) instead of from 0 to 10 (10x the end of the curve).

Try changing the code block 0..10..#25; that goes into Curve.PointAtParameter to 0..1..#25;.

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Thanks, Jacob — you’re right, the 0..1..#25 fixed the overshooting issue.

Just to clarify:
I’m trying to divide a NURBS curve into equal parts, and then extract each individual segment — for example:
Point1 to Point2, Point2 to Point3, and so on — basically to get the connecting lines between each pair of points.

Which native nodes would you recommend for that?

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Depends on how you define ‘equal’.

Mathematically splitting by parameters is ‘equal’, but you may get segment lengths which are not equal. As an example if you build this curve:

NurbsCurve.ByControlPoints(Point.ByCoordinates([0,9,10], 0, 0), 2);

And pull the point at parameter 0.5 you’ll get an X coordinate at 7, though you might expect a value of 5. This is because the degree and weighting of the control points which make up the curve impact the resulting parameterization of the curve.

If you want even lengths you can use Curve.PointsAtEqualSegmentLength or one of the similar PointsAt methods to generate points at what you likely intend for spacing along the curve. These points can then be which can then be used to split the curve.

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