This node creates controlled random variations. The variation source can be attribute- or primvar-based. Primvars should have a constant detail (a single value per object). Only non-zero id/primvar/attribute values will create a variation. If the source can not be read, there will be no variation. Being able to lookup an arbitrary float or int attribute is a good way to debug a scene. For examples, if you are wondering which objects are single-sided, you can enter 'Ri:Sides' in varName.
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