Physically Based Rendering In Directx

Physically Based Rendering In Directx

So I want to implement a Physically Based Rendering system in my Render Engine but after looking at all of the siggraph presentations online,

I've got to admit I don't understand much due to the fact I'm not that good with math and cannot understand any of the equations in the presentations. I was wondering if someone here could explain how to implement this. 

 

I was reading this article: http://ift.tt/2aEBPWk

Which kinda helped but I still don't understand a lot of it, so I'm downloading the code sample to see how it works.

 

So all I understand is that you just need to blur a cubemap based on a variable. 

 

Basically if someone could explain PBR to a 3 year old that would be great.