Hey! You guys have been busy!
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Nice looking shader there, Serg! I haven't looked at your attachment yet (I'll try to get to it today), but it looks real nice.
@jrgauthier: Here's your fixed file. The problem: you were trying to access the attribute as a local variable, where none existed. The MeasureSop was indeed creating the attribute with the name you gave it (“CURV”), but it desn't create a attribut->localvar mapping for you so you can't use it as a variable later on in the chain. The way around this is to create the attribute plus its variable mapping
before using the MeasureSOP (which simply overwrites its value). Then it's available
as a variable (as well as an attribute) lower in the chain.
Hope that made sense (it's been a long weekend and I'm probably not making much sense). Anyway. Have a look at the attached fixed version and see if it clears things up for you.
Cheers!