ToonShading PostProcess Makes One Prop Face Always Shadowed?

Dying for help on this, tried to google and read answers hub, but so far no luck. I’m sure I’m missing something obvious.

I followed this epic live tutorial for the toon shader: Post Processing in UE4: Cel-Shading | Live Training | Unreal Engine Livestream - YouTube

My result looks great EXCEPT for the fact that one face of every prop (facing the same world direction) is always in shadow. This happens irrespective of skylight/point light/spot light, etc.

If I rotate the static mesh, at one point in the rotation it suddenly snaps into being a lit face, and then again becomes receptive to dynamic lights.

The lit faces respond to dynamic lighting, the shadow side never does.

I know the issue is in the Post Process Volume setup, because it goes away after removing the PP volume.


I’m attaching an image showing the behavior.

Also, want to mention that this 180degree side that is always forced into shadow, happens without any lights in the scene. It also happens if I place a directional light pointed immediately back at that shadowed face.

Something about the PP Volume/Toon Shade Material is uses, is producing a strong black shadow on on side of all meshes.

Attaching an image showing the shadows cast by that directional light, but also that the faces directly hit with the light are still black.