Description

Sub surface shading model has strange blotch color artifacts when used with ambient cubemap. Since the subsurface profile shading model can't be used with ambient cubemap I wanted to use the regular subsurface shading model but it has visible artifacts when used with ambient cubemaps. These are not affected by opacity for some reason. When used with regular lighting they seem fine, you can't see light on the other side through the mesh. 

Found in 4.22 CL# 7053642, 4.23 CL# 8386587, and 4.24 CL# 8971176

Steps to Reproduce
  1. Open the attached project
  2. Open the "subsurface bug" level
  3. Move the camera up and down while looking at the purple sphere

Results: 

You see the color change (when the sphere is in the bottom of the view it looks normal, when it's at the top it's very colorized. When dragging there's a visible line (in the middle of the screen) where the color changes. Also this isn't affected by opacity at all which is strange.

Expected:
It is affected (lit) by the ambient cubemap but there are no blotchy artifacts or color changing when you drag the view around.

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By Design
ComponentRendering - Features Teams
Affects Versions4.224.234.24
CreatedSep 23, 2019
ResolvedSep 25, 2019
UpdatedSep 25, 2019