How to add attractor point/curve to 3D Voronoi surface?

Hey all,

I’m an Industrial Design student and I’ve been trying to teach myself Grasshopper for the last month or so when I find time. I was successful in adding a 3D voronoi pattern to my custom surface, and lofting that surface, plus adding weaverbird components as well.

Now I want to be able to add an attractor point/curve, specifically so that the holes on the top are open wider, and begin to close the further down the hood design. However, I can’t seem to figure out the solution to this problem.

attached I have my .gh file, custom surface, and some screenshots. If anyone can help, that would be much appreciated!!

Thanks !
Hood_Voronoi_Weaver.3dm (8.4 MB) (24.5 KB)

Is this what you’re talking about?
(weaverbird was not installed correctly in my pc, so I suspect that the last few components of the definition are missing, but the relevant part is intact) (88.4 KB)


You can also achieve a quite nice result without an attractor, by remapping the z-values of your Vornoi cell center points to their scale factor.

I also got rid of the surface lofting and surface to mesh conversions. Since you seem to be after meshes in the first place, you can go directly from polylines to meshes, instead of wasting processing power on creating Nurbs surfaces first.

Since you produce your cell outlines/polylines by intersecting a three-dimensional Vornoi with a double-curved surface, your cells aren’t planar! This isn’t dramatic, however it may lead to some inconveniences down the line.
You may for instance notice that performing a fixed Catmull-Clark smoothing, results in a bad mesh, due to intersecting faces. My guess is that this is directly linked to the non-planar cells making smoothing difficult. I’ve set it to “smooth”, which is fine, but this relaxes the naked, outer edge of the mesh, which might not be what your after (cf. screenshot)?
However, if you for instance want to 3D print the object, producing a good mesh is imperative.

Since you are a design student, do also note that planar cells would make fabrication much simpler (depending on the process). (20.0 KB)

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Yes! this is exactly what I was looking for. I have done attractor points before, but I had never put them manually on a surface like you did. Thanks for all your help!

This is also a very useful answer, Thanks! I don’t have any experience 3D printing these complex meshes, so I was unaware that my non-planar cells would create such a problem with the Catmull-Clark smoothing down the road.