Triangles on Sphere by predefined Points

Hey Guys,

I'm kind of starting out with grasshopper and have a problem that seems to be easy to solve having the required knowledge.

I am having a perfect sphere generated in grasshopper, there are straight lines starting from the center of the sphere intersecting it, these intersections are my given points. Now i want to generate a triangular grid out of these points.

The triangles don't need to be mapped on the sphere, so the curves connecting the points can be straight, although if they are arcs I don't have a problem with that either.

Here's a pic of the sphere, the given points on the surface have a circle around them (they don't matter though).

The thing you see in the pic is going to be something like a joint, if I could get my triangles, i think i'll be good to go on defining it.

Thanks,

- Harald Lesan

Attachments:

sphere.PNG, 118 KB
question.gh, 4 KB

Replies to This Discussion

Permalink Reply by Vongsawat Wongkijjalerd on December 7, 2016 at 11:27pm

Seems like this is a bit of a non-trivial problem (why half of the default tools in this area are fixed to 2d) but after getting lost in 3d voronoi/delaunay threads, finally cottoned on to the fact that what you actually want is a 3d convex hull..

Finally found Mateusz Zwierzycki's 3d Convex Hull (the latest version)
http://www.grasshopper3d.com/forum/topics/incremental-3d-convex-hull
and then you just extract mesh edges.

(I replaced the Line inputs as you didn't internalize them in the initial file, so just replace them back)

Edit: just found out that the component is included in the Starling Plugin under slHull3d
http://www.food4rhino.com/app/starling?ufh=

Attachments:

questionv.gh, 9 KB

Permalink Reply by Harald Lesan on December 8, 2016 at 9:57am

Thank you very much! I really apperciate your effort to help out and the best part, it just works perfectly.

I was prepared to map the surface onto a plane, so i could create a delaunay-triangulation and then map it back onto the sphere, luckily i don't have to do that now :)

Have a nice day

- Harald Lesan

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