Hello, all you grasshopping rhinos! I’m new to Grasshopper and I can’t figure something out… I’ve generated a triangulated mesh and extracted all the faces, edges, vertex normals and face normals. The one thing that I really need but can’t get are the edge normal vectors. I can calculate this vec…

There used to be the Sandbox plugin but you can use a small script too. I think Daniel Piker posted this a while ago. File with c# script which outputs internal edges and indices for left and right face: mesh_angles_c.gh (31.2 KB) This one here uses a kangaroo component to get the hinge points: …

That works really well, cheers! Butl if you’re offering to code to order, I’ll be a bit more specific, because that “moved” mesh collection is really what I’m after and all the other bits (edge quads, vertext tris) I can do myself, (along with anything else that might crop up as I develop this thing…

hah! no, if anything I prefer keeping things in component land. I’ve tried learning to code many times in my life at this point and I keep bouncing off. I just get lost in the abstraction (despite knowing full well that abstraction is what makes it a better and more flexible approach).The visual nat…

Just don’t connect the panels to inputs… I’m still looking for a way to avoid the flip matrix component.

Alas, I get some exceptions. The majority of the edges come out of Peter’s C# component in the same order, but a handful are different. When I try and create meshes from them, I get these self-intersections as a result: [image] I think my fate lies in Peter’s hands now… Simple tile 2.gh (18.1 KB…

Are you just trying to offset the surface and put holes at the vertices? And do you need the surface as a mesh?

Well, I didn’t know how to offset the mesh, so if you are willing to use the Pufferfish plugin for its Offset Mesh component, this will create you your mesh: [image] Simple tile 3.gh (26.9 KB)

The holes are a by-product really. If my source was a flat plane or a sphere or a torus, then every face would have similar vertex normals and an Offset Mesh would then also have identical edge normals resulting in coplanar edges (left). But when the vertex normals are all over the place, it twists…

[image] Tom Newsom: linear subtraction Well … in the latest C# attached that works by computing pts - given the Edge diherdral Vector3d as the unitized sum of the adjacent Faces normal Vectors - on both sides of the Edges (i.e. Line.PointAt(at), Line.PointAt(1 - at)). The at var varies from s…

Yes, I already have some edge length checking in the main project and the subtraction amount is limited to a fraction of the minimum reported length. Thanks for your help!

I am so confused. [image] Tom Newsom: I need those quads to be planar for Reasons, so I’m sacrificing vertex continuity to achieve it. What quads?

Mesh - Edge normal vector

Grasshopper

Volker_Rakow (Volker Rakow) August 8, 2025, 10:44pm 26

I gave a shot at emulating your script. I managed to circumvent the need for edge vectors by creating offset surfaces with Plane Region:

Newsom Concrete Panels VR 1.gh (53.2 KB)

a component, I have to say, I have never actually used before.

How To Extrude Panels Evenly?

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Mesh - Edge normal vector

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