Where can I find LobeRoughness and LobeEnergy function?

Development Rendering
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1

I’m trying to test custom BRDFs. I see that StandardShading models use LobeRoughness and LobeEnergy function
but I can’t find where they are. I’ve looked in to most of the built-in shader.ush files. Someone help please!
And does Default Lit material use StandardShading function or StandardShadingPerLight function?

2

These two parameters are related to spotlight. If it is directional light, LobeRoughness is Roughness, LobeEnergy = 1