Material using Subsurface Profile turns white when lit by Ambient Cubemap (post processing)

A material using Subsurface Profile turns white when lit by the Ambient Cubemap in PostProcessVolumes. I was hoping to add a slight tint to the lighting with the ambient cubemap, but instead the character turned grayish. When lit by only the ambient cubemap it’s basically white. This seems to happen in both 4.14 and the 4.15 preview 2.

Steps to reproduce:
Add two spheres. Create two materials, one with the opaque shading model and one with the subsurface profile shading model. Create and add the subsurface profile to one of the materials. Disable all lights and add a skylight with the cubemap setting, in my case using the EpicQuadPanorama. The spheres should both be red. (like this)

124501-skylight.png

Disable the skylight and add a PostProcessVolume and add the same cubemap to the Ambient Cubemap texture and set the intensity to 1+. The opaque sphere should be red and the subsurface profile one should be white.

124480-ambientcubemap.png

I have no idea if this is a bug or by design but I would really like to have a character with subsurface profile shading lit by an ambient cubemap (as well as the skylight cubemap).

Hi cyaoeu,

This was a known issue that I just made public. Here is the link: Unreal Engine Issues and Bug Tracker (UE-40531)

You can track the report’s status as the issue is reviewed by our development staff. Please be aware that this issue may not be prioritized or fixed soon.

Workaround You can revert this behavior by entering r.sss.checkerboard 0 in the console or put that in the ini settings.

Cheers,

Ah, I didn’t know about the workaround. !

It’s doesn’t work , and still not fix.

It should probably be r.sss.checkerboard 1. It does work though. :stuck_out_tongue:

I’d like to add that this problem also occurs when using subsurface-profile materials with the light propagation volume and thus also having the same workaround by re-enabling the SSS-Checkerboard rendering.

I can’t find the console settings to change this, and no other posts actually explain where this " r.sss.checkerboard 0" is or how to access it. Can someone actually provide an explanation that explains how to fix it? Half a string of code doesn’t help me change or find anything, and I’ve used both the help tool and looked through project settings without finding anything by that name.

check it

set r.sss.checkerboard to 1 as cyaoeu said