Mesh - Edge normal vector

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 vector but how do I return the faces of a shared edge?

Is there maybe a plugin for this? Rhino 8, btw.

Thank you in advance!

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: (31.2 KB)

This one here uses a kangaroo component to get the hinge points: (39.2 KB)

Thank you very much! This is the magic I needed!

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See attached as well (conn is about the adj Faces indices). (128.3 KB)