Containing isotrim grid within a complex surface


I have been learning grasshopper and have found an issue the I can not seem to solve. I want to apply an isotrim grid to a complex surface to get the grid, eventually offsetting all the edges and crating a structure. When I made the grid it was not bound by the surface boundary and when I tried to trim the grid with the boundary of the surface it did not seem to work.

I feel this there is a simple solution that I am just not looking at

Can someone help me solve this issue?


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In case of a trimmed surface,Surface Splitsometimes fails in 3d for various reasons, such as a tolerance issue.
One way is to work on the plane and then move the result to 3d trimmed surface using Copy Trim.

Gaz (15.8 KB)

Thank you very much, that is a huge help but not I am stuck on something I again am sure is an easy fix

The bottom edge does not have vertices except the one corner when it is deconstructed and all have a value as 0 not allowing me to select points though a list item

Gaz (15.8 KB)

Thank you so much!


I referred to other topics and saw that someone was in the similar situation. As I know have surfaces with 4 and 5 vertices I am having a hard time simple making subsurface. I downloaded turtle but unlike other plugins it will not appear.

How can I just easily make surfaces if I have all the edges and vertices ? I have tried various ways as you can see with no luck


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Awesome Thanks,

But this now leaves me with it being read as 2 surfaces when the centroid of the surface is found (one center point for each triangle)

Ultimately I am looking to offset all the edges from each surface (the vertical and horizontal lines that divide the surface) an equal distance and offset that surface. Would i use construct domain to achieve this?

Thanks for the help, just a Rhino guy trying to learn this powerful program

Would connection all of the points to create lines, then using boundary surface to create the surface not work?

It’s not planar boundary, so it’s not working…

I was just unsure if there was a way to manipulate the list to make it work out.

I got as far as getting the look that I am trying to reach but am sure there are all sorts of errors in the workflow.

The main issue is that the centroid of a triangle is lower than the other shapes. Can this be corrected?


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