# Geometry Nodes: "Instance on Points", but parametrized

Hi, as part of my Geometry Nodes learning process, I would like to make grid of generated objects. Like this grid of arcs, hopefully each of them with different angle. As you can see, it doesn’t work like this.

I know I’m doing it wrong. But how to make it work, please? Do I need to “rewrite” Arc node into a Node Group with lots of math? I’m out of ideas again…

I just tried and this is what I achieved, is that what you looking for ? You can also change the x and y rotation, here I used only z in the random value node ,

I would think so. The inputs of the primitives do not allow fields at the moment.

I know I can easily rotate, scale and translate instances. But I would like to generate them completely separately. What I want, I wouldn’t even call it an Instance, it’s just a bunch of independent, separately generated objects.

Arc is just an example for easy showing what I want to do. The goal is a grid of more complex parametrized structures.

If the structures you want to instance all have the same number of vertices, you can access them individually after the realize instance node. Then you just need to figure out the math how to manipulate them.

I see…
well I am new to that so maybe I cannot really help or even imagine what you want as a final result.
What if you use object info somehow , with distribution on points maybe. you will be able to generate different object.

I don’t know , I think this won’t help you , I will follow the discussion hopefully someone will came up with the solution.

P.S. I love you addon(Audvis) man, thanks !

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For not to complex structures you may work something out on the realized instances afterwards as @LordoftheFleas suggested.

Or when you need just a few instances you can make manual copys of the parametrized geometry and join them as a collection of instances.

But if you want many complex parametrized geometries, then unfortunately AFAIK there is no good way to do it. A few weeks ago there was an idea for a node for generating such instances on the development chat. But never heard of it again.

For me this is just another use case for the loops which were planned quiet a while ago, which i hope are still on the agenda. But the devs have been busy with other things lately. They would make creating the parametrized instance collection super easy.

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Thanks all for informations, it helped me. I’m not able to watch all the rapid Blender development.

Ok, I have some kind of parametrization now. Still can’t use the Arc node for example, only building custom geometry “manually”.

1. store “Normal” into named attribute
2. delete faces and edges
3. extrude using stored Normal attribute from step 1
4. convert mesh to curve
5. Subdivide Curve with parametrized Cuts count and do whatever you want
6. convert curve to mesh

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Here is some concept:

.blend file (mp3 not included):
spaghetti monster.blend (1.0 MB)

Main node view:

Node Groups:

basic lines:

noise:

shake the curves:

endpoints (the arrows):

curve to mesh: