I’m trying to get a flat diffuse render out and I’m finding no matter what I do - if there are lights in the scene I get specular highlight information. In this example image the base material is a flat emissive, the outline around it is where the shader has specular enabled via a mask.
To get a true “unlit” diffuse pass I have to turn all lights in the scene off. For production meaning in my render passes I must make a second pass just to get my diffuse.
I ran a few more tests just on the deferred rendering unlit setup. This render preset does not display only base color as the documentation suggests, it allows specular information in as well. This alters the base color or diffuse and is therefore unusable as a base color pass.
To add further clarification here - I am toon shading my scene; this means I am using the emissive channel for color NOT the base color channel. Unreal is set up to deliver a base color pass in the basic post processing material sets which is great but for people like me who don’t need to use the base color channel it creates either a need for a workaround or a need to integrate that channel and it’s values into my setup. More on my adventures with base color roughness here: https://forums.unrealengine.com/t/removing-light-influence-from-base-color-channel/498834/2?u=srwld
Currently my method is a parameter switch in my shaders that kill all specular influence, I have to render my diffuse out in its own separate pass which is a bit of a time creep but at the very least is a solution.
