Feature Request - Atmospheric Fog color

So unless I’m just completely blind (which is a definite possibility) you can’t change the Atmospheric Fog color. It would be really useful to be able to change this so you can simulate the Atmosphere of other planets. For example if you want the sky to be green you can’t get it to be dark green because the Atmospheric Fog is stuck as a dark blue.

Tried to use

And changed the “Fog Inscattering Color”?

Haven’t used fog at all by now, but this seems to be what you are searching for :X

Thanks for the suggestion eXi but that’s the exponential height fog which is meant to simulate fog in the world. What I’m talking about is the Atmospheric fog which is used to simulate the atmosphere of a world. Essentially its a distance fog that blends the outer portion of your world with sky sphere. At the moment there’s no color option that I can find in the atmospheric fog.

(: Hmpf, yes now that you mentioned it, i mixed them up. Sorry!

Maybe faking it with post process color? :smiley:

yes you can even fake it with the Exponential height fog which I did do thanks to your suggestion. Still though its quite a bit different if you ever stand on top of a mountain or something higher than the fog’s height it ends up looking like a sea of fog. I suppose a work around would be to make the height higher than the highest point the player could get to, but I think it would be better if Epic simply allows us to change the color of the atmospheric fog.

When using Atmospheric Fog, the sky/fog color is linked to the Light Color of your DirectionalLight with AtmosphereSunLight to true.

I managed to get a green sky using this method but it changes the level lighting along with the sky color :-/

Maybe you can start from here and find a way to get the sky colored without changing the level lighting.

Thanks for the suggestion but I already played around with this. Far as I can tell there’s no way to change the atmosphere color without affecting the lighting of the level.

There is a way, but you need to change the shader code for this. I’ve played around with the parameters for my master’s thesis. You also need an understanding of how Rayleigh and Mie scattering work.
But basically in the AtmosphereCommon.usf there is a parameter called BetaRayleighScattering and a parameter called BetaMieScattering, they are 3-float vectors representing RGB values.
The Rayleigh values represent Earth’s blue sky and are based on physical measurements.
The Mie values are plain white and simulate fog and haze in the distance, close to the ground.

Here’s what happened when I increased the Rayleigh red value by a factor of 10

Hi, I made changed in “AtmosphereCommon.usf” to set black color for ground but nothing changed in AtmosphericFog Actor (in scene) except that I must waiting to recompile all shaders.

I tried:

BetaMieScattering = float3(0.0, 0.0, 0.0);

or

BetaMieScattering = float3(0.0f, 0.0f, 0.0f);

Can you help? Where is my mistake? Thanks.

Would love to hear from Epic as to whether or not this is possible or something that they might implement in the future. There’s likely a lot of people who would love to be able to change the color of their skies without being forced to use sky domes etc that look terrible.

3 years later, I’d love to know if there’s a more simple way to change the color of the sky. The Sun Disc is tied to the atmospheric sky color which really makes this something that a lot of people could likely benefit from as the only types of worlds you can easily simulate this way are those located on Earth.

Where do you find this file to modify it?
I’m guessing Angel Tsvetkov, the reason you can’t make it black is likely because this is an emissive material so you can only use colors that are in a positive value. 0 (black) doesn’t register with emissive.