Random sprite sizes with Mesh Reproduction Sprite (Niagara)?

Hi guys,

The Initialize Mesh Reproduction Sprite (Particle Spawn) used in conjunction with Update Mesh Reproduction Sprite (Particle Update) is giving me problems with sprite sizes.

From what I understand when using these options the particle size is meant to be set in the ‘Sprite Size’ field in ‘Update Mesh Reproduction Sprite’. But if I want a random particle size which I attempt to create by selecting a Uniform Ranged Float makes the particle change in size in every frame (clearly because I’m in the Particle Update area). This because no matter where I try to set the particle size under Particle Spawn it gets overwritten by the setting required in ‘Update Mesh reproduction Sprite’.

How do I get a random sized particle if I’m forced to set the particle size in the Particle Update section? It gets recalculated every frame.

This may be awfully simple, but I’m coming from Cascade so I’m just getting started with Niagara. Thanks in advance!

Create a float in particle spawn name it anything like mysize then link your sprite size from particle update reproduction. Now you can use uniform for mysize.

Thanks a bunch! I’ll try this out.

BTW your YouTube channel is awesome! Love your videos! Subscribed! :slight_smile:

Hello! Just got back to Niagara again and I’m sadly stuck on a similar issue. If I’m using Mesh Reproduction Sprite to create sprites with a different width and height (Vector2d), and I need to both have a random starting size and also change their size by life I can’t make it happen.

If I create a vector 2d and link it on particle update reproduction to later to make a random size on particle spawn I can’t change the size by life on update anymore (how?). If I change the size by life on Update Mesh Reproduction Sprite, I can no longer set the uniform size because I encounter the same issue I had before.

I can make the random size or change the size by life separately, but I can’t have both happen simultaneously. I’ve tried setting it up dozens of ways but it won’t work…

I miss Cascade :frowning:

Yey! Figured it out shortly after posting. Just had to add a Scale sprite size module in Particle Update and change the ‘Initial Sprite Size’ from ‘Particles/Initial/SpriteSize’ to ‘Particle/Initial/MySize’. Your previous answer helped me figure it out. Thanks again.

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