Ribbon UV offset through dynamic parameter bugging out

Technical & Engine Help Unreal Engine Help
#1

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so i have a ribbon spawn from a location event of soul particles.
i want to give each ribbon a unique offset per ribbon. im not sure why but the ribbon just gets all compressed if i try to add an offset. ive attached my material graph and niagara system above.
any one know why this happens?

thanks

1 Like
#2

Ribbons are made out of strings of particles. You’re selecting a different offset for each particle in the ribbon.
You can fix this by making the offset based on ribbon id for example.

#3

I tried using the beam ID on the left, but it makes no(or very little) difference in offsetting the uv’s

#4

If you only spawn it once, it might be id 0 every time

#5

If you only have one beam per emitter, you can also generate a random value on emitter spawn, and use that as the offset instead of a random per particle

#6

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I tried making a scratchpad on Particle Spawn

Is there something I’m doing wrong?
Sorry very new at this

#7

Probably want override seed to be enabled as well

#8

ok so i made a debug emitter

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i made a scratch pad inside particle update. seems to be working.

EDIT: after further experimentation the problem is within the calculate random range float node. it seems to calculate a random value for each particle hence the distorted effect. using “Seeded Float Random” works just fine