Truncated Extrusions from curved Surface

Truncated Extrusions Sample.3dm (42.4 KB)
Truncated Extrusion Spikes (10.1 KB)

Hello Grasshopper community! I would really appreciate some help at the moment!

Essentially, I am attempting to extrude truncated blocks (spikes) from a divided curved surface. I would like a range of the degree of truncation at the ends of each extrusion (pointing towards the center of the curved surface, such as the drawn sketch.) I seem to be getting the extrusions from the divided surface, yet running into errors when trying to truncate.

Is there another method to achieve similar results?
Or am I making a mistake in the script prior to truncating?

I have attached the script for reference. Any help is appreciated!

Hi @Matthew_Scholtz

Truncate is not suited for geometry processen.
It is used to skip values from a list of values.
It is not clear to me what you would like to achieve.

Instead of straight extrusions you can offset each sub-surface and loft the boundaries. You can offset the boundary of the offset surfaces to create a truncated look.

Truncated Extrusion Spikes (34.7 KB)


Hi Erik and Martin,

I appreciate both of your responses. Thank you for clarifying my misunderstanding, I thought the truncate function was more related to truncated geometry such as the truncated cone or pyramid.

Also, thank you for the workaround!