Particle Expression: Particle Random Value Documentation?

Hey all… I am doing some particle / material work. Can somebody explain the Particle Random Value / ParticleRandom expression to me? How is it driven? I don’t see it listed in the docs.

107201-particle_random.png

( Particle Expressions | Unreal Engine Documentation )
Thanks so much!

this gives a random 0-1 value for any particle spawn. so one particle will have a value of 0.01 another 0.99, and another 1.0… etc.

forgot the amount of variation but it was either 32 or 64 different values between 0.00 and 1.00.
So if you hook this up with i.e. a hueshift each particle can have another color, etc.

yea, afaik it only works for gpu particles.
(sorry, forgot to mention that)

Thanks for the quick reply… Does this work on GPU particles? I’ve got it hooked up to a debug node and it’s showing all .0000 for me.

Until I saw this node I was using Particle Size to drive randomization of colors and it was working with GPU particles so I would imagine this should work as well.

EDIT: Ummmm actually I didn’t have a GPU data type on that system… as soon as I added a GPU type it worked… is this the expected behavior? ie not working on CPU particles?

Cheers!