Liquid materials PBR+SSS (blood, milk)

Graphics Shaders & Materials
1

Hi guys,

I have a question. I’m new to PBR shaders and learning how to simulate different materials with PBR and struggling with finding info how to simulate liquids.
Wood, metal, rubber, etc are pretty straight forward. But what about liquids. I have to make blood, milk and ocean materials in my next project. Can’t find anything.
I know that liquids should have SSS and fresnel. But how exactly it should be done for standard unity metallic PBR.

  1. You can’t tweak fresnel in PBR shaders but instead its a part of softness - which is very confusing.
    Even if I turn off softness and metallic to 0, the material still has reflections - that’s super weird
  2. SSS is the most confusing. for example for the ocean - the sun should come thru just the upper waves - how am i doing that? or for the other liquids even more mysterious.

How people normally simulate these materials? are there any references or places w reference values for liquids?
All PBR examples I found aren’t liquid. Even in Substance Designer they dont have SSS which is confusing.

Pls, help :>

2

@
the animation is not the problem.
I’m more looking how to make the material that it has proper feel. like the surface.
ok maybe ocean wasn’t the best example to ask. im more looking for how to simulate semi transparent blood which is darker in the middle and more transparent on the sides.

3

You could look into using some of the existing SSS materials on the play store, they’re fairly cheap.

For fresnel, perhaps this page will be helpful:
https://en.wikibooks.org/wiki/GLSL_Programming/Unity/Specular_Highlights_at_Silhouettes

4

@Invertex thank you.
I’m surprised actually coz i thought fresnel is a part of standard PBR shader.

about PBR fresnel unity is saying this:

“In the Standard shader there is no direct control over the Fresnel effect. Instead it is indirectly controlled through the smoothness of the material.”

5

i found this article how they do in blender / i wonder whether its possible to make it in unity.