Split Mesh Strips via Directional? Blender import into Rhino/GH

Hi, thanks for dropping by this topic! I am working towards fabricating my sculpture model. My sculpture is initially modelled in Blender and then imported as .iges (NURBS) into Rhino. I’ve converted to mesh, planarized quads, and joined mesh strips via U directional (circular strips). What I would like to do now is split these mesh strips at the four corners and four midpoints (as seen on the images below). How can I achieve this? The objective is to split these mesh loops down to a reasonable size, then unroll and then cut on the CNC. Thanks in advance for any help!

I would also want the strip/quad heights to be variable (like shingles) by using the bottom edge (as seen on the image). In case anyone has a definition for that already as well.




Mesh Split.gh (1.1 MB)

Here’s a method creating “Quadrants” that you can use to group panels in per quadrant.

It leverages the fact that your form is symmetrical, using a polygon to create triangle zones and then groups the panels by each panel centroid per intersecting triangle zone quadrant.

I don’t have the stripper plugin you are using so I grouped your panels, if you plug the strips themselves into the “Area” component that I currently have the individual panels plugged into, the logic should work just the same and group your strips as you desire.

Alternatively if you run the stripper algorithm on the grouped panels output in the script I provided that would achieve the same result I believe, as it would be “stripping” per each branch of the data tree aka Quadrant Grouping.

Let me know if you get stuck.

Cheers!

Each color represents a different Quadrant:


20230608_Mesh Split_Response_01a.gh (1.1 MB)

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It’s better if you complete the job in blender by selecting seams, unwrap and export the shape as obj.
Import it to Rhino and simply explode the mesh.

mesh.gh (30.0 KB)

shape2.obj (37.1 KB)

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Morning.
Just partition it.

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Hey, thanks for the response! However, I need to figure out how to complete this in GH for more efficient interoperability. There’s actually a lot more geometry that goes with this sculpture, I just had not internalized that data for simplicity. These are actually just the top panels which will be cut out of aluminum and applied as shingles. If by any chance you have advice for the second question I would greatly appreciate it! extruding the bottom edge of each mesh strip downwards to overlap like shingles.

Thank you! I really appreciate this response. I did not know I was able to group panels in this matter, which was the entire reason I installed stripper (it does simplify the definition a lot more, should give it a shot if you’re interested!). I will definitely try this out, my concern is just the reliance on the symmetry of the sculpture may not stay, as it’s massing is still going through iterations. Just developing a definition early on to figure out how fabrication will work. Any advice for the second question about extruding down the bottom edge to give a shingles assembly?

Quan Li, MVP! I don’t have all the plug-ins I need installed on my current PC, but will check this out first thing in the morning once I get to studio. By the way, this definition that you attached, was it the right one? Again, a lot of components for me are grayed out right now, as this pc is missing the plug-ins. Also, any advice for the second question about the shingles effect would be appreciated! I’m assuming I should be able to just take the boundary edge and extrude downward? I will play around with it in the morning

Grayed out? Can you post a screenshot? Let me see it.
There is only one plugin, the stripper. It is for getting mesh UV. Though the mesh face sequence is random, the uv is consistent. So means you can use it to reorder the sequence.

Yes, of course. Attached is a screenshot of the definition you have attached. I downloaded Kangaroo and stripper so the components aren’t grayed out anymore (not on the PC I’m usually working on. will have access to that in the morning).

I believe this is a older script from when you helped me rearrange the mesh using stripper, as it does not have the partition list coming out of list item (also what do you have coming out of partition list? don’t believe I ever used that before and if I have it looks much different).

In the script I attached with the questions I split the mesh into strips via directional (as per the image of the circular loop). However, if I go to unroll that with the Unroll Mesh Strips component, it asks for no loops. Therefore I would need to split these loops I have already created before unrolling. And ideally to fit the CNC for fabrication, I would want the cuts to be at the corners and center.

Not really sure how to use path mapper if someone could direct me to some tutorials for this threds question? Seems to be the solution to splitting the mesh loops (circular loops specifically, not vertical strips) at the corner seems and center (as per images). Learning partion list to path mapper might also help me resolve another portion of this sculpture later on.