Particle parameter not working for 'Initial Size'

In both CPU and GPU emitters, I have a setup exactly like this one, except I do this in Construction Script:

… And it doesn’t work. No matter what value I set as parameter from blueprint, it doesn’t change.

I Slavq,

This isn’t a bug, this is how the Construction Script is supposed to work. The value is generated when the asset is created and stays that number, You can easily see this is you set a vector variable that is set from the Make Vector node then just setup it to print on event tick or keypress from the Event Graph to show the value.

If you want to setup any sort of random streams values in a Construction Script you can check out this video here for a demonstration: - YouTube

Thank you!

Tim

Oh, thank you, I didn’t know that. But what I actually try to do is to just set the ‘Initial Size’ particle parameter from Construction Script, it doesn’t even need to be random.

For example, have a ‘Fire’ blueprint with particle system and parameter like ‘sparks size’ that I can change from blueprint variable (so it passes the value to particle system to change sparks size via ‘Initial Size’)
So sorry if I misunderstood, but something like this is not possible in Construction Script?

Just use the Make Vector node and plug in any values you need. This works on my end. But passing a variable value back to the construction script isn’t going to work that I’m aware of since the way it is handled when the actor is placed in the world.

It’s best to handle the variable value change via the event graph where you can set a variable and adjust this.

Had this same issue and it turned out to be a problem with gpu particles. Normal particles will scale. You can use a make vector if you want the scale to be one number or use a vector.
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