Shifted list duplicates the last element

Hi all,

Working on my mesh again, I got an issue:
When generating all the triangles, the last row would get duplicated, making the final join operation impossible.

I hunted the issue down to this list of booleans (red), the purpose of which is to dispatch (yellow) all the concentric rings of points between the rings which have the same amount of points (blue arrow) and those in which the amount of points doubles (green arrow). the issue seems to be that the boolean list goes [0,1,…,n], but the triangles creation uses the elements [0,1,…,n-1] and the elements [1,2,…,n], thus the boolean list was too long and seemed to create an extra row of points, creating an extra row of triangles on the outer rank (I hope my explanation makes sense)

So I though that simply using two sublist elements to create the [0,…,n-1] and [1,…,n] lists would fix the issue: well, it does fix it for the blue arrow section, but for the green arrow part the triangles don’t generate anymore.

and now I am a bit stuck.

Thank you in advance for your help

0227_IBO_mesh-log-grasshopper.gh (32.5 KB)

I see you chose to stick with your manual process :slight_smile:

Thank you for your help last time, but when I opened your file it didn’t work on my computer and I decided to not press the issue as to not clutter the forum and because I was too short n time to look into

What didn’t work? Maybe because I did it in Rhino 9… You do get an error message loading the Rhino 9 file in Rhino 8 but the file runs fine. I just tried in my Rhino 8

In case you can’t see the mesh edges press ctrl+m with the cursor in the canvas.

I opened it in WIP to check and still got the same issue:


the error message on R8 while opening the file goes as follows:

Yes and now with the cursor in the Grasshopper canvas please press ctrl+m

wow, it worked, thank you

what does ctrl+m do?

So is this a duplicate thread?

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