Mesh To Brep

Hi There. I have created tetrahedrons and I’m trying to find the normal on each of the four sides of the geometry.

I have used the attached script to do so with cubes, however in creating the tetrahedron, it has created a mesh (which i have used script to create a Brep). It is recognising that there are four normals on each side of the tetrahedron. How can I quickly and easily recreate this geometry with only four faces rather than 16?

I would really appreciate any help ASAP as I have an assignment due in 7 hours and I’m super super stuck…Tetrahedron Normals Script.gh (8.8 KB)



Tetrahedron.gh (7.6 KB)
Why do you create a Brep then convert it to a mesh and again convert it to a Brep?
You can directly get surface-normals from your Brep like this:

If for any reason you need to convert it to Mesh, you don’t need to convert it back to Brep:

Thank you - I’m very new to Rhino and Grasshopper and so I thought it was outputing a mesh

Hi Mahdiyar,

What I am trying to do is to grow out from that tetrahedron using mirror and scale, please see attached script. I think the reason I went back and changed it to a mesh was because I couldn’t get the geometry to generate at the other end. I’ve attached the full script here. Can you see what I am doing wrong?

Thanks very much for your help, it is greatly appreciated!

I couldn’t see any attachments.

Sorry - here you go.

Tetrahedron - Mirror at normals and scale.gh (8.2 KB)

Did that attachment come through ok?

Is this what you’re trying to do?


Tetrahedron-Mirror&Scale.gh (4.8 KB)
The problem is the PlatoTetra component generates an Invalid Brep. you can fix this Brep by joining its faces together, or you can create a simple pyramid without using this component.

I have spent six hours trying to work this out today - going insane.

What is the component that you use to close the brep? I want to go on to use octahedron and dodecahedrons, so was hoping to get this script right.

Have you checked the attached file?

I didn’t understand what Beep you mean? You mean the final Breps?

Yes sorry - just found it.

Thank you so so so much for your help. You are a lifesaver!