Closed mesh made of points in space

[Parametric_Tom]

Hi! Im trying to make a closed mesh (sphere style) with the points I created, but for some reason I am not getting to the result. Anybody knows what can be missing? I am not a frequent user of Grasshopper, I would be very grateful if somebody can help me out!

FrecuenciaCardiaca5.gh (20.6 KB)

[René_Corella]

Can’t really work with your file as it comes in like this (and I’m missing your plug-ins):

Is your closed mesh supposed to include or be made of all the vertices?

If not, you could grab a 3D Convex hull from the MeshEdit or make a ‘point volume’ ?

You can also internalize the points and share that file to get some quicker help

[Parametric_Tom]

René,

Thanks for your answer. This a definition without plug-ins and with the other parts erased.

I tried using a 3D convex hull, but couldnt make it happen. Maybe I was using it wrong.

FrecuenciaCardiaca5.gh (10.1 KB)

[René_Corella]

@René_Corella

Is your closed mesh supposed to include or be made of all the vertices?

What about this?

[Parametric_Tom]

Made out of all the vertices. That way I can change the form depending on the length of the amplitud and the number of points I create.

[René_Corella]

FrecuenciaCardiaca5.gh (9.5 KB)

You can probably use 3D Delaunay cell (from MeshEdit) plus “Alpha Shape” from @laurent_delrieu:

Alpha Shape 3D

Here is an implementation of 3D alpha shape, it is using 3D DelaunayCell (standard GH component ??). https://doc.cgal.org/latest/Alpha_shapes_3/index.html https://doc.cgal.org/latest/Alpha_shapes_2/index.html I liked a lot the explanation of Alpha Shape of CGAL site “Imagine a huge mass of ice-cream making up the space R3R3 and containing the points as “hard” chocolate pieces. Using one of these sphere-formed ice-cream spoons, we carve out all parts of the ice-cream block we can reach withou…

[Parametric_Tom]

Thanks René! And is it possible to do it without script?

[laurent_delrieu]

As it is ordered it is not a great complexity to recreate a mesh

I just has to repeat first data to close the mesh on the meridian.
FrecuenciaCardiaca5.gh (12.7 KB)

[René_Corella]

Awesome as always Laurent - I was about to say it seemed the alpha shape method, or the point volume method, still left a point here and there unaccounted for. Thanks. How would you close this mesh? Fragment patch on the naked opening?

[laurent_delrieu]

Thanks.
I will add points on the pole and make a fan. Delaunay mesh could also work. But I had no time it is time to sleep in France.

[René_Corella]

Ok, kick ass - Rest up!

[Parametric_Tom]

Thank you Laurent! And if I want to smoothen the new mesh, what would you recommend?

[laurent_delrieu]

Catmull&Clark or SubD

[Parametric_Tom]

Thank you very much Laurent! Very grateful! Is there any possibility that you can send me the last definition please?

[laurent_delrieu]

not so much change
FrecuenciaCardiaca5.gh (8.2 KB)

[Parametric_Tom]

Thank you!

[giusseppe]

Hi Laurent
This works in ver 7 but doesnt seem to work in 8 even though I installed “normalize”.
Do you have the same problem ?
Giusseppe

[laurent_delrieu]

I will have a look but I still don’t use R8 by default as I didn’t purchase it.
I also try to install ghshadernode without success. Normalize doesn’t appear.
Normalize just duplicate data ! So I change it with simple components.; I closed the mesh with Pufferfish component
FrecuenciaCardiaca5_RH8.gh (19.9 KB)

[Parametric_Tom]

Hi Laurent, I tried closing the mesh creating the polar points and using delunay (like you told me), but havent managed to close it. Is there any other way to do it?

[laurent_delrieu]

There are many ways
Or you extract the points from your list
Or you extract Naked Edges and you join them then use points.
I also added a middle point.
Delaunay must work if you provide a plane

Then join mesh …
FrecuenciaCardiaca5_4.gh (20.5 KB)

You can make a fan, on middle point connected to 2 consecutive points

FrecuenciaCardiaca5_5.gh (18.2 KB)