Groom Hair with Expo Fog

Development Rendering
1

I’m testing to see if these work together in 4.24.3 - and seeing strange shading on the hair when it interacts with exponential fog. Just wondering if anyone else has had any success with these working together?

2

I think I’m having the same issue in 4.25.
It just looks like the hair is ignoring the fog completely :\

3

In .25 you can force it by creating a custom hair material and using the new material inputs for sky athmosphere/light.

Doing this and following the hair guide should likely result in a better shaded / more natural material, since you now have access to the light as a vector input.
however keep in mind that point lights would not be accounted for. So maybe you would have to mix/match the 2 methods based on another parameter switxh which you control on the character via BP.

Would be nice to just have an all in 1 solution wouldn’t it?

4

I am encountering the same problem. Your solution sounds nice but I can’t seem to figure it out… Could you show what the material nodes would look like to set-up? I would be very grateful!

5

Hi,
as of a few weeks ago you can get the bodes you need from this page

This page explains how the light affects the hair

In essence, use the light vector to increase/decrease the scatter value, which should provide a more realistic look since that’s what light does when it comes to contact with hair.
probably using wpo because you want a per pixel effect based on the surrounding geometry.
I’m thinking offset with the fresnel mask like the example shows for other things, so that edges are lighter.

You have to play with it and see what you can come up with.
the light vector should be avaliable to the pixel shader as i was waiting on .26 to get it on the vertex shader as well…

6

Well, it seems we won’t need work arounds anymore! 4.26 Preview 1 notes seem to say that hair is production ready and is now fully integrated with fog and other effects! I’m yet to test it out though

7

Hi, I need a solution to this ASAP. Can you post a screenshot of the material setup please?

1 Like
8

any solutions to this in 4.27?