PxrVary
The PxrVary pattern allows for random variation. Let's try varying the color of the teacups based on the Particle ID.
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This causes a primvar called particleId to be available on the instances.
Next, wire a PxrVary pattern into the color of the material used for each of the cup and the saucer.
Set up the PxrVary to use the particleId as its seed for randomization.
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