So a while back on this forum I had asked if somebody could explain PBR to me, and most of the responses I got were to first implement basic lighting with diffuse & specular maps and then move on to more complex lighting. Now that I've done that I've gone through a few siggraph presentations that have helped me understand what PBR actually is. I was having trouble implementing this in my engine, but then I stumbled across this blog post: https://dirkiek.wordpress.com/2015/05/31/physically-based-rendering-and-image-based-lighting/

which explained everything quite well and included a sample to show how everything worked entirely.

However the sample used DirectXTK and since I am a beginner it was extremely confusing to understand how things worked since there were so many files to go through just to find a simple Material Struct. So far I have only written my engine with 1 header file, 1 cpp file & 1 effects file (I know I should use classes and additional header files to make the code easier to read and work with but for the time being I just want to get PBR up and running and I will then re-write everything for ease of use).

I'm not trying to ask for someone's code or to help me copy/paste code but could someone help explain how the direct lighting brdf's (forget the Image Based Lighting Part) are working in his sample?

This wouldn't have been a problem but I haven't had much experience with something like DirectXTK.

I tried to implement what you said but I still can't get anything to work. All these papers and talks about PBR are great but I honestly need a good sample to look at to really understand and implement it. Any ideas on some resources that have samples or show how to implement PBR? I'm beginning to consider to stay with my current lighting system because of the lack of tutorials for PBR available on the internet. The one I found https://dirkiek.wordpress.com/2015/05/31/physically-based-rendering-and-image-based-lighting/ is good but uses DirectXTK which makes things a pain in the ass for a beginner.

Maybe this helps: https://www.shadertoy.com/results?query=pbr

I guess it's easier to go from OpenGL shader than from full DirectX sample

I know this sounds demanding but could someone write a tutorial for the implementation of PBR? I feel entirely lost when it comes to implementation since there are hardly any tutorials, there are a few presentations and papers but I'm not at the stage to be able to understand these equations and be able to implement this without any help.

Theory is always an approximation to the real world. The you further approximate when implementing a renderer. I feel the trend that the last approximation, to get it real time, is becoming less significant.