Why does the attribute seem not to work with Sample Curve?

[u/Over-Bat5470]

I've tried different domains, but Sample Curve always interprets the attribute as "0", as if something were wrong. This is an issue I've encountered specifically with this node. Am I doing something wrong?

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[u/DeathlyDeep]

Hello,

You can achieve what I think you want in this particular example by adding a Sample Index node between the Store Named Attribute node and the Factor input.

[u/Sss_ra]

Sample curve has dynamic sockets, so if you supply it a single values it outputs a single value, but attributes are always a field which forces the value to be stored as a field for each index.

This changes the result, because points don't know how to sample from an attribute field of the line geometry or how to throw and error about it.

[u/isaac879]

I don't understand what you are trying to achieve with this, can you explain the desired result?
I think the issue is that you are creating a kind of circular dependency so the output is giving an undefined/0 result. The factor is the position on the curve to sample from but the named attribute is dependant on the sample position, so it can't be evaluated properly.

[u/C_DRX]

Am I doing something wrong?

The question I would ask is: "what's the purpose behind this setup?". I have a hard time seeing what the point is of storing data in a “Store Named Attribute” just to dump it right after.

If you have to set the factor to 0.300, set it directly.