[sowbug]

Also look at the source for original Quake (https://github.com/id-Software/Quake), one of the last pure software-rasterizing AAA 3D PC games. Michael Abrash's Graphics Programming Black Book (https://github.com/jagregory/abrash-black-book) explains many of the critical parts of the rendering pipeline.

By the way, quake.exe for DOS was 404,480 bytes.