Single random value in Blender 3.0 Geometry Nodes?

I’m trying to familiarize myself with Geometry Nodes, but I’ve already hit a problem.

I want to create a single random float value to adjust the scale of an object. I thought this would be trivial, but it seems Geometry Nodes isn’t that simple.

The ‘Transform’ node requires a single vector or value, but the ‘Random Value’ node outputs multiple values, resulting in an error:
Blender3.0_geometry-nodes_random_transform_error

Searching led me to a page in the latest Blender manual referring to the ‘Random Float’ node (https://docs.blender.org/manual/en/latest/modeling/geometry_nodes/input/random_float.html).

This looks like what I want but the node is not in the list of possible nodes in Blender 3.0. Presumably the manual is either out of date or premature.

How do I obtain a single random value in Geometry Nodes?

Hmm,

Try plugging in the ID.

this seems to work, in 3.1 (I have no idea why atm)

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What is really counterintuitive is that you have to assign the ID backwards, you have to pull the ID from the random node into the group input.

An existing ID node confuses just more than you would expect to fill the random from that ID node, which is not working. I would consider this a bug, or is there a reason for that?

I think these are different ID’s here

That is a point Id node,

I think Blender is using an Id similar to the ones it creates for instances here for internal handling. So it needs an Id setting for Random.

Just a guess though.

Thanks. That works :grinning:
It seems much less intuitive than the simple ‘Random Float’ node, but I’m still trying to make sense of how the whole ‘fields’ thing in geometry nodes is supposed to function.

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I agree that the whole ‘assign backwards’ thing seems counter-intuitive. I assume there’s a reason for why geometry nodes functions as it does, but so far I haven’t seen an explanation for it. :confused: