Help with unrolling a combo of breps?

Hi guys,

Still trying working on this, my first GH project. I’ve read a few threads about the challenge of unrolling breps when you’re particular about how you want them unrolled.

This is what i’m trying to do:

As I don’t know any scripting I’m thinking a workaround might be to just nudge one of the vertices away from the others, thus pulling the edges away from each other ever so slightly (to a degree that won’t impact on it’s fabrication).

I’ve tried importing a guy Hornero’s grasshopper user object posted from another thread but that didn’t work for me unfortunately.

Before I start on my workaround method are there any other suggestions of how to achieve this?


Architectural model (166.1 KB)

Still a bit of a workaround as don’t know how Rhino defines how it unrolls breps but this seems to work in this case. I used Jitter to mix up the list of surfaces before joining. Then out of interest i added a little bit of extra code to unroll and lay them all out. As unroll puts them all on (0,0,0) this is the same even if you write code component.

Maybe having an unroll component with a plane input option is something for GH 2.0 Rhino V6 please, I realise this may need to be added to Rhino Common First. Forgive me if its already an option not had a chance to play with V6 lately. @DavidRutten

Architectural model 1 - (170.3 KB)

Ps. Could anyone tell me how Rhino defines what edges to join when unrolling breps and how this can be controlled when making Breps. @dale

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The edges that get connected when not all of the 3d ones can be connected in the flat model comes from the order of faces and edges in the internal brep structures and is not at all user controllable. That’s just not part of the way it was designed or set up.

Thanks Lowell, Good to know. As i understand it with code and maybe grasshopper too you can build breps to have the order of faces and edges you want though. Maybe i am wrong on this but i remember working though the issue of edge order when making Edge Srf in the past and i think i found a solution.

Yes, you can do that if you’re deliberate about it. The array orders can change by edits that add or remove faces.
I think it’s possible to do what you said, and I hope it works out.