Animation speed of a VFX Prefab

Unity Engine
1

Hi guys,

I’ve downloaded a VFX Prefab collection from the asset store.
Got it to work and like it quite much, I’d just like to slow it down.

Now there is a very handy “Play Controls” window that pops up whenever I select the prefab.
It has a “Rate” slider, which lets me select the speed. Let’s say for example I put mine to 20 and like the effect.

However after selecting anything else in my Scene, it just resets to it’s default speed again (100), how to I save my changes? There is no button on the Play Controls window that I can find that does that.

Thanks in advance for your help!

7509800--925892--Play Controls.PNG
7509800--925892--Play Controls.PNG1091×555 762 KB

2

Hey,

Unfortunately, that window is just for previewing the particles. To my knowledge, to change the speed of a particle system without using code, you’ll have to manually change the various velocity properties of each of the particle systems contained in your VFX prefab. This is a huge pain.

Luckily, this isn’t very difficult to do with code. I made a simple script to change a particle system’s speed:

using UnityEngine;

[ExecuteAlways]
public class ParticleSystemSpeed : MonoBehaviour
{
    [SerializeField] float particleSpeed = 1f;

    ParticleSystem ps;

    void Start()
    {
        ps = GetComponent<ParticleSystem>();

        var main = ps.main;
        main.simulationSpeed = particleSpeed;
    }
}

Remove the [ExecuteAlways] line if you don’t want this updating in the editor, and only at runtime.

You need to attach this to every object in the VFX prefab with a ParticleSystem component, and then set the speed for each one in the inspector. There’s definitely a more efficient way of doing this, but I don’t know what your prefabs look like.

To have the speed update in the editor, you’ll need to reload the scene, or exit the prefab view, and re-enter it.

If you have any questions, feel free to ask. Also, I’ve tested this briefly, but I’ve never needed to do anything like this before.

3

Hi,

Thank you very much for taking the time to write all that down!

I’ll be able to test it with the script soon, thank you!

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