Geonodes - Align triangular faces on an icosphere

Hello everybody.
I haven’t been there for a while … I have a problem with a job I’m doing and you can probably help me.

Basically I have to create triangular-based pyramids (cones with three subdivisions) “implanted in an icospera” (therefore upside down).
With Geometry Nodes I instantiated the pyramids on the faces of the icosphere and then I aligned them with respect to the normal ones. The problem is that the triangles that make up the base have a standard rotation and do not touch edge by edge.

The reason is that later, some of these pyramids will have to rise above the normal ones and once they are far away, scale slightly and rotate around their own pivot point.

So the questions would be:

  1. How do I rotate the instances so that all the triangles have their sides aligned with the others? (mimicking the underlying icosphere?)
  2. How do I make instances move along their Z axis (perhaps using a noise texture)? I tried, but the system works for the scale but in the case of the position I don’t get what I want.
  3. How can I once these move away from the central sphere to scale them and above all rotate them randomly?

I’ve also attached the file I created to make things easier if you’d like to help me out :slightly_smiling_face:
I uploaded the file to weTransfer, I discovered that Pasteall is unfortunately dead =(

Thank you very much for the help you will probably be able to give me!

I tried a slightly different approach. I used an icosphere with an edge split in the nodes. I extruded the faces and joined them to the base.

The only problem I have is that I don’t know how to blow these pyramids. Not being instances I have no idea how I can go about animating them using a map. In addition to this, the origin of these elements is at the center and I have no idea how I can change it to be able to animate them.

The file can be downloaded here.

Thank you again for the help you will be able to give me! =)

Yeah this is a bit problematic… rthe triangles are:

  • not all the same size… which may be neglectable… but
  • have normals which not necessarily points to one of the edges so instanciating a 3-sided cone doesn’t fit

I though about the old instanciate child object workflow… (for a start) which then would have to be made real… but there are also some quirks…

Yeah, that’s almost the solution… Do this:

… can drive the inputs here with textures instead.


It’s fun to play with the parameters.

Good luck.