Multiple offset of Polyline, or Alignment

New to Dynamo, any help wold be appreciated!!! :-{)
I thought I would start with something simple, I want to be able to pick an Alignment or a Polyline and have it create multiple offsets left and right and put them on the correct layers… ie… I want to pick a center line and have it create BOC, EOP, and FOC lines on both sides at specified distances on specified layers. I have installed the Civil3DToolkit. I Tried playing around with the different nodes in the library of libraries, but not having much luck… The code block seems very promising, but did not have much luck figuring it out.

Any help would be much appreciated…

Thank you,


Hi @btillett,

Check this out if you haven’t already, it might help you get started.

Thank you for the quick response. Yes, i downloaded that and cannot get it to run… it has way more than i need, I am still trying to figure out enough to get it to run on an alignment I have in my dwg. If I can figure that dyn out, it should help me create the simpler one that we would like to use.

Much appreciated,


OK here is a simpler example for you to try.

OffsetsExample.dyn (44.9 KB)

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Thank you, that looks like exactly what we need. But it does not run. the list is empty?
Any ideas why the “Curve” and the “list” would be “Empty List”?

Probably just need to add the layer input on the AlignmentExtensions.GetGeometry node. By default it will get the alignment geometry on a layer named C-ROAD. It’s set up that way so that you could, in theory, get geometry for things like tangent line extensions that aren’t really part of the main alignment geometry.

So if your alignment is not on a C-ROAD layer, then add that input with the correct layer name.

YES!!! Thank you… I had tried adding the layer name with a “Input, Basic, String” but that did not work, but when I put the Alignment on the C-Road layer it worked. How would I change the layer to our standard layer for alignments? Any idea what this error message means, or how to clear it so I can tell it still applies? I apologize for all these questions!


That’s the answer! Just add a string input with your standard layer name.

It means that the geometry is very far away from the origin, which is common for civil projects. Don’t change the Geometry Scaling as it says…leave it set to Medium otherwise there will be other issues that crop up down the line. There are a bunch of posts on the forum if you want to read more.

You can use a Function.Apply node to bury the warning, but be advised that this will bury all warnings, not just that one. So use it carefully.


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