Draw a polygonal curve through a series of points in geometry nodes

Question

A cylinder comes with vertical edges and horizontal edges. I want to create curve which starts at a top vertex, goes down a horizontal edge to a bottom vertex, then goes up to the next top vertex, down the vertical edge to the bottom vertex, and so on around the cylinder. I would like to do this in geometry nodes so I can play with the parameters.

I have tried to create a cylinder, convert that to points, then draw a curve through those points, but after extensive googling, there is no simple way to draw a polygonal line through a sequence of points, even if they are indexed.

I have tried creating a circle curve, duplicating it, translating one copy, and then reconnecting it. Again I can't see how to connect them within geometry nodes. Any suggestions?

Answer 1

• Answering the question title (Draw a polygonal curve through a series of points in geometry nodes):

In Blender 4.0, you can use the Points To Curves node to create one or multiple curves using a Group ID for each and weights for the point order.

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• Answering the question content:

To create a sawtooth wave curve from a cylinder, triangulate it with fixed order and delete the top and bottom edges before converting to curve:

Or if what you want is a square wave: delete each other edge from the top and bottom with a $1$ offset for one side before converting to curve:

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