I'm trying to create a material that will let me plug something into the emissive slot so I can have a single light in a scene and have simulated bounce light on the back of the model. I've been able to achieve a similar effect by using a hacked together inverted lambert in the custom lighting slot, but I want to be able to plug it into the emissive slot so the backlight is visible even when shadows are turned on.
Here's an image of what what things look like currently with the inverted lambert shading on a really quick and dirty lumpy test model:
And the ultimate goal is to achieve something similar to the shading in the Dota 2 comic:
Thoughts, ideas, whatever? I've been noodling around with this all day and I haven't been able to come up with a solution that works. I'm by no means a shader guru, so any help would be appreciated.