The A.I. Of Doom

Btw, much of this state machine based ai already existed for wolfenstein 3d. I don’t think it did line of sight checks, instead using sound carried within and between rooms connected by open doors. U can read about that in Fabiens also fantastic Wolkenstein book: https://fabiensanglard.net/gebbwolf3d/

https://www.doomworld.com/25years/

The AI is certainly limited, but the maps too, Doom not being a true 3D engine. The core mechanics is walk into a trigger, it's either a trap or a puzzle. It's really fun, and you don't get the impression that the AI is not up to the task.

I however like to play with a mouse, and use modern weapons from Beautiful Doom. Unlike Brutal Doom, Beautiful Doom was careful to preserve the original game. It makes weapons a bit more powerful, but you need to reload them. This makes combat a bit faster, a bit more challenging, minus the use of mouse that makes combat easier. Beautiful Doom has been compatible with every WAD I played so far too.

https://www.moddb.com/mods/beautiful-doom-6100

I like to use GZDoom, without texture filtering, and with software sector light mode that emulates the original look, and smooth fuzz style for rendering invisibility. The default options are too bright, and invisibility is too visible. Most maps are designed for the original look too, it's worth approximating it.