In every scene that I’ve seen (and certainly mine) fire examples always have static shadows. Even with a light function the original shadows from a point light are static and do not reduce in intensity. How can I have moving shadow from (fake) fire ?
Here is an example from the valley of the ancient demo
in red are the shadows cast by the point lighting faking the fire. However they do not vary in intensity or movement. The light function does a good job at creating varying intensity of the light, but shadows doesn’t move which doesn’t make a lot of sense. My light function also have panning texture and movement.
I tried to enable cast shadow on the niagara fire but it doesn’t work
How can I fake those moving shadows without creating a blueprint with a timeline of a point light moving sideways/up and down randomly ?
here is a quick gif of what i’m trying to do in regards to the shadows
cheers
Hi,
First off, this is a very nice attention to detail!
Question: Why wouldn’t you use a blueprint with a light in it as you showed in you gif ?
I don’t personally see any options to cast moving shadow except from light source or emissive (with Lumen). Make sure to enable ‘‘cast distance field shadow’’ from your light source, it might help also getting better shadow quality.
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Thanks for the reply.
If it was for a personal project, i would use a blueprint with a timeline, although it looks more like a workaround. It’s definitely a solution though
But i’m working on a bigger project with different people and it seemed to me like a messy way to go about it, I was wondering if there was another solution that would be more realistic
Also I don’t know if it’s me that has the wrong image of a fire in my head and that thinks that shadow should be affected a well ( I mean maybe how it looks in UE is how it looks in real life and I’m wrong) but it seems weird that shadows aren’t affected from a light function (or that there isn’t the option) right out of UE
I’ve also heard that using a timeline is a tiny tiny tiny bit worse for the performance, not sure if that’s true 
Hi,
Well, one of the words I heard the most about Unreal Engine is that you have 24 000 ways to do the same thing. In fact, the way the shadows move is due to the light source of the fire, moving with the flames. So in the end, I do not think that making the fire inside a blueprint (Niagra and light) is a wrong or messy way. Actually this is how I would do it. Because, for instance, if you wan to expose any parameter on your fire, like color, scale etc… You’ll need to make it in a blueprint either way. See it as a container.
You can always try to use a light function but I’m not that expert with Light Functions unfortunately. But my guess would be to go Blueprint 100%
Cheers 
