I'm discovering the wonderful world of math and I'm hitting a huge wall with PBR and naming so I have a few questions: As far as I understand BRDF describe how a material react to light (incoming direct light and reflections). But in "Cook-Torrance" I don't see anything about reflections I don't understand how I integrate it so I only get diffuse light and reflections.
I've read a lot about different "diffuse term" like "Oren-Nayar" is it a part of Cook-Torrance like a different "D" in the DFG nominator ? does it replace it without specular calculations ?
I've read a lot about "GGX" from my blender artist background I thought it was something that make a blurry reflection but It seems I was wrong and now I find this GGX term in a lot of different situations like in micro-facet normal distribution in this tutorial
So in short the question is: how "Oren-Nayar" and "GGX" and "Cook-Torrance" are related to each other (if they are) and how do I integrate "vec3 reflection" in those algorithm ?
As I said before I'm a newbie in math so If your answer is "math heavy" please write a glsl/hlsl version of your equations it's much easier to understand for me so an equivalence will help me a lot
PS: I understand my question is blurry but it is also as blurry as my understanding of the subject.