Beginner - Help Making a Geode Pattern

I’m new to Rhino and Grasshopper, and am struggling to make a random geode-like pattern on a surface. Mainly with making extrusions from a voronoi that end in a closed point. Any pointers on where to look for tutorials? I’ve attached the grasshopper file if anyone can have a look and tell me where I’m going wrong.

Crystal (16.0 KB)

And that ?

Thank you for the quick reply, I can’t seem to get gh files to work, I think maybe they use plugins for older versions of Rhino? (I am using Rhino 7). Are those plugins essential for getting any results from grasshopper?

I don’t think plugin are essential for this. I must have used them to generate some input mesh. If you have R7 triRemesh could do the trick to have nice triangular mesh, useful to make the dual (hexagons mainly).

Thanks for the tip, I’m starting to get somewhere, but there’s still a couple of error messages stopping me. Any idea what it is I’m doing wrong? Sorry for being so slow on this its all very new to me!

crystal growth on surface v2 with organic (333.9 KB)

crystal growth on surface v2 with organic (100.3 KB)
You wanted to make too much things? Just plug the output mesh to that! Choose the side, and play with sliders, if too slow double click on the slider to put the value



That is very helpful, thank you. However, I am missing MeshFlip and MeshDual nodes, and although I have installed the necessary plugins, they still do not show up. Would this be because I am in Rhino 7?

Never mind I made sure to unblock everything and it works perfectly! Exactly the kind of thing I was after. Thank you for the quick replies, super helpfull!

Mesh dual is an old script from forum. There are now alternatives to it. Voronoi is quite or exactly the same results.

For Mesh Flip I don’t know where it comes from but it is not mandatory

Hi I used this code but I only changed the mesh input, should I change anything else?? because it is not showing…
crystal growth on surface v2 with organic (100.3 KB)

it works here.

So if you just post a file that is inchanged from other post and that worked. How could we help you ??


code (29.7 KB)
model rhino1.3dm (12.8 MB)
those are mine

it is not necessary to post all the models, post just the relevant one. You could also internalize a geometry in you file (search on the forum if you don’t understand)
You didn’t do a lot of work to try to understand how my script was working. You should read more carefully the explanations in various discussion on this subject.

But whatever, the important thing are these one
*You work very far from origin so there could be some strange behavior of Rhino.
*Your geometry is quite big so be carefull when you remesh it with triremesh. I used a length of one for the edge but as your geometry is 32000 units I use a LENGTH of 1000. Play on this length to adjust the size of the crystal.

  • Whatever the geometry you use you’ll have to convert it to triangle/Dual Mesh in order to make crystals.

Here a file working.

code (37.6 KB)

yess i couldnt understand it very much because this is my first semester using rhino+grasshopper and also i have big ideas… anyways thank you SO much for ur help will do several geometries to practice this one