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UE4 - How to activate Niagara VFX while using Sequencer for Cinematics?

Hi, it´been imposible to actívate a Niagara VFX inside the Level Sequencer, no option to switch actívate ON and OFF, like you do with Legacy Particle System, where you simply choose “Deactivate, Activate”

How to make it work?

Facing the same issue. It’s obviously possible to key the visibility but then it still has to compute the effect in the background, so it’s not ideal. Anyone knows the proper way to do it?

what happens when you render output movie with ‘simulate’ on ?

There’s a System Life Cycle track under NiagaraComponent. You can use that to activate and deactivate niagara particles from sequencer.

There seems to be a limitation though in that only one life cycle track is allowed per Niagara component. Which means it’s not possible to toggle one system on and off.

​Yeah, it looks like you can have only one life cycle per Niagara system. But it is still possible to activate and deactivate it with it. When you right click on the life cycle and look into the properties, there are some life cycle settings, so you can set it to be active only during that life cycle and deactivate it automatically when it ends. You can also select different modes of activation and deactivation based on what you’re looking for. So basically it will be active during the “red” Life Cycle track, and it will automatically turn it off afterwards.

https://forums.unrealengine.com/core/image/gif;base64
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Yea tried those. Still no luck activating a system that has been deactivated on the same track. Does it work for you?

It looks like for whatever reason Unreal doesn’t allow that. There are two workarounds for it though. One of them is expose spawn rate from Niagara as a user variable and than you can control it with the sequencer - so you could set it to 0 when you want to turn off the particle and to whatever number you want when you want to activate it. The other way would be to have that particle system as spawnable in Niagara and respawn it, or spawn multiple systems.

Okay, I found a solution for it. It’s still a bit of a workaround but it should work exactly how you want. Just add event track under your particle system and add trigger event. Add a keyframe, right click on it and under the Event select either Activate (NiagaraComponent) or deactivate (NiagaraComponent):

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https://forums.unrealengine.com/core/image/gif;base64
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By default that event will be called only in the game but if you right click on it, under properties there’s an option Call in Editor, so just tick that and it should work exactly like you want.

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It’s working, thanks SouryGame! Those parameters should just be exposed directly. Well maybe in the future.

Just in case someone finds it useful:

https://www.youtube.com/watch?v=rIkpu358Hak

Thank you very much #9 SouryGame right answer helpful。thankx again。

I made a fire using a Niagara system and I’m using the “Point Lights Component Renderer” to make the fire’s light cast shadows on the wall. It works well in simulation but can’t see it in exported PNGs. Wondering how can I make this “Point Lights Component Renderer” be active while exporting? Thanks!