Niagara question

I am beginner in Niagara. Сan you explain to me what I need to do to move the “Add Velocity” to the “Particle Update” as in this video (time stamp 5:37) :
(512) UE4 - Niagara Ambient FX - Dust / Fireflies - YouTube
This worked in UE4 but in UE5 it doesn’t.

Did you ever end up figuring this out? I watched that video as well and saw that 2 people in the comments thread asked this same question, and his responses were:

“Yeah they changed it, you have to have an until velocity and then in update you can add velocity”

and

“In ue5 you need to have an initial velocity in particle spawn for add velocity to work”

In both cases the OPs asked for clarification and didn’t receive an answer. I’m going to assume by “until velocity” he meant “initial velocity”, like in his second answer. I’ve been looking high and low for such a parameter but haven’t been able to find it.

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@anonymous_user_35c7dafb I just ended up using a noise force (which is detailed just afterwards on that clip) and seemed to do much the same. In the end it wasn’t clear if the ‘add velocity’ method was meaningfully different…

Not sure if you guys have figured out, I am currently using 5.3 and I found out having same question as you were. In 5.3, I tried to move “Add Velocity” module to Particle Update, and it was reporting
image

And when I went to Particle Update Velocity modules, I could not find Add Velocity in it, even though I have Add Velocity in initialization. And btw, in initialization, add velocity cannot be adjusted by using curves, same as color. Because it is not a update method, not changing from time to time.

This drew my attention, I started to question why 5.3 is behaving like so. They call it “Add Velocity” while inside “Initialize Particle” module, there is no space for setting up initial velocity. And surprisingly, they allow users to use curve setting up initial velocity while it is not changing anything except for T=0.

The workflow I am currently using is, set a velocity like 100. Go to Update Particle, use curve to scale it. I do not like this workflow, but this is the most cost saving method I have tested.

Another thing I want to add, there is a very simple way to do that but I would never recommend. Go to Solve Force and Velocity and use curve to set velocity over time. The reason why I am not recommending it is because this is a module combining all physics calculation of this particle. All variables inside of it should be a “Add-on” to its previous computed result, instead of using this as a curve editor setting velocity over time.

The reason this no longer works is because you should only work with forces in particle update, not velocity directly. Forces will be multiplied by the tick delta time in the solve forces module, but when you add velocity directly your particle speed depends on your framerate.