How to simplify a Surface into a regular triangular Mesh?

Grasshopper
1

Hello everyone,

I have Rhino and Grasshopper for Mac.
Since a few days i’m trying to transform a surface into a regular triangle mesh.
I’m not very good at grasshopper so i tried to find a resolution in this Forum, but i couldn’t find some for my example.
Maybe there is somebody out there who can help me with my problem, what would be very nice.

Every Help is welcome.

Here you can find my files. Thanks a lot.
3D Meshing.3dm (15.2 MB) Meshing.gh (106.4 KB)

2

look at the meshmachine component in Kangaroo2… not sure if it works on mac tho.

3

With Grasshopper I tried to work with the meshmachine, but because i am new in grasshopper don‘t know what i should do

4

Hi,

What do you mean by “regular triangle mesh”… all the same size edges? You can use the Mesh command in Rhino directly followed by TriangulateMesh to get all tris. Does that help?

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If not, explain more about what you need from the mesh. The polysrf has some issues at the poles of the trimmed ellipsoids but perhaps those won’t matter. I’m not sure you need GH here unless I’m missing something.

5

Hello sailor!

I’ve checked your surface and there seems to be a problem with the way it is modeled. If you run the check comand in rhino you will be able to see that it is not a valid surface.

BORRAR
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You should probably model it again in rhino by lofting a series of contour curves generated from the bad surface like this:

hhh
hhh1378×725 116 KB

for the part of the mesh creation, after you fix the surface you can do this:

Canvas%20at%2017%3B41%3B22
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mesh_example.gh (9.4 KB)

best regards,
Sir Ernest Shackleton.

6

Thank you very much for your help. I do exactly mean all the same size edges. If that is anyway possible.

I try to rebuild the surface and will use the GH file from Ernest Shackleton. Thanks a lot for that.

best regards

Christophe

7

The surfaces don’t mesh so I agree rebuilding those is important. The tips of the ellipsoid forms (poles) are the main factor in the polys becoming smaller in those areas when meshing simply with the Mesh command. If you can model trimmed surfaces without poles in those locations you may be able to use the detailed mesh controls to get evenly sized polys. Otherwise, it does seem GH would be needed.

8

Hi, Thanks for you answer.

Maybee you can tell me if it is possible to create a surface from points,witch i put on the surface.
Cause when i rebuild the surface by lofting, the sides will be not close.

Any ideas?

9

The Patch command can make a surface through points and also trimmed by a closed curve. Here I used all curves to make a patch surface.

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Why do you require equal length edges in the mesh you’re trying to create? I think you can get close with detailed meshing of a trimmed surface but I don’t think it will be perfect.