Rendering – Problems.
I wanted an occlusion layer to get that added effect however it is extremely difficult to get transparency to work on it. Especially when that transparent surface has reflections and refractions on it.
How it can be fixed:
Texture Baking. Texture bake everything underneath the transparent surface. In this case, Hogan’s head. This will allow the occlusion to stay on the head and accept refractions. This was quite complicated and I was sleep deprived so I decided not to use this.
My shaders were toons. I had to change all my shaders to a Mia_Material so that I could put ambient occlusion on the shader itself. This lets the glass shader work with the surrounding scene. I used this method because though tedious, was very easy to do. I left the eyes as toons because I wanted that vibrant flatness that stands out from the rest of the character.
Another option is a Python script here. Applied to everything that the glass shader moves in front of will fix this problem too.
It can be used for other things as well but its probably best in a not so busy scene. It also makes alpha planes work in an occlusion layer which is absolutlely brilliant.