Help to find information about id tech 4 engine architecture

[ballinlike]

Hey guys, I have two questions...

I am presenting the id tech engines 1-7 in a lecture for my studies.
Even though the code is open source, it is not so easy to find information if you are not so familiar with the engine.

 

1. can you help me to find information about the engine architecture (engine components)... by that I mean for example which third party SDKs (NVIDIA PhysiX, Direct X, etc.) are used? What does the core system look like? etc. 
In the attachment you can see what I mean.

 

2. what do i need for components (programs, editor, etc.) to work with id tech engine 4 for example and what does the user interface look like for that?

It would be really great if you can help me. 

 

[Shepardus]

Maybe start here: https://fabiensanglard.net/doom3/