Coding along Handmade Quake by Philip Buuck
His repository is at: https://github.com/philipbuuck/HandmadeQuake
My code is probably going to be a little bit different from his, since I'm trying to code things on my own and not just copying what he is doing.
Unfortunately, Mr. Buuck could not continue with this project and the videos are no longer available on YouTube, so I didn't advance on this either.
https://web.archive.org/web/20180117023005/http://philipbuuck.com:80/handmadequake