Hey there,
I’m fairly new to UE4 (did some maze building and runtime mesh stuff some years ago) especially when it comes to lightig. At the moment I’m trying to get a bit used to UE4 and maybe in some future I might want to do a small game.
But for now I had the Idea that I want to do some Digital Festival Stage/Hall Kind of Music Visualization for live streaming or YT Vids. On one side I want to try to do some of the effects based on the Music itself but also with user input to trigger stuff.
To start with I created a FPS Project and made my level dark, added an ExponentialHeightFog to mimic the fog machines used to make the lightshow more visible and added a bunch of spot lights.
On Imgur: The magic of the Internet I have screenshots of the light and fog settings, a screen of the BP to move red lights and a short video showing the result.
Now coming the my question/problem.
While I’m kinda proud of myself that I got so far, it feels pretty ugly to see those artifacts at the beggining of the light cone. I found that I could use the console command “r.VolumetricFog.GridPixelSize X” to set the fog grid size to X pixels and tried that. In the video you can see that it start with the default of 8 and over the time i change it to 4 and later to 2 (you can see the size change in top left corner). while changing from 8 to 4 makes it look way better without affecting performance too much the FPS is almost halfed when going to 2 while the improvement there is not as good as in 8 to 4.
So my first Problem is: The artifacts. Kinda solved by using a grid size of 4.
The second (kind of) Problem i that there is also a visible delay between moving of the cone and the lightspot on the ground. Here I’m honestly not sure if I even want/need that but depending on the stage setup it might be nice to have the spot… but it even might no big deal to have the delay… i don’t know.
And a potential third Problem: Even with grid size of 8 there is a trace of the cone when moving and the trace becomes more visible with higher grid size… not sure if one wants this behaviour in a light show.
TL;DR while with my fog and light setup the blue spots look pretty good with grid size of 2 it hits performance and moving lights have some potential issues. and this situation made me wonder if there are better ways to reach my goal than the light+fog way. While trying to get to my current state I did lot of googling to get it working and found no question about a similar goal.
I found one alternative solution to this in a question regarding a flaslight cone where the suggestion was to use a 3d modeled cone instead of light+fog. but there the question was more about light shafts.
I recently saw some vids about the possibilities of Niagara and wondered if this might be a way to attemt this project?
To have a better picture what i want to achieve:
or in a way bigger scale Defqon.1 Weekend Festival 2016 | Da Tweekaz - YouTube or Defqon.1 Weekend Festival 2017 | Defqon.1 Legends | 15 Years of Hardstyle - YouTube
I hope someone can give me some good advice or hints.
Thanks in advance, stay healty <3