Improve stealth

[tukkek]

This is just an idea but the fact that robots always attack you on sight (even when other enemies don't) always seemed like one of those things the developers didn't quite have the time to address before releasing the game. This point is also a sore-thumb that sticks out in many reviews for the game - for example, at 6:10: https://youtu.be/oPrU7LSqiX0?t=370

The fact that other enemies don't also become hostile when robots do and things like secret passages facilitating a stealthy approach being immediately thwarted by a sentinel shooting at you further compound on my assessment that this wasn't the original gameplay vision but instead something they couldn't quite get right (or done in time) before releasing the game - back when patching post-release was almost unheard of, almost impossible to notify players about and very slow to download.

The easiest way to approach this would be to make all enemies (including robots) only attack when alarms are active - or to trigger an alarm when a robot attacks the player. However, I imagine this can be simply done and the original developers could have gone with that if they thought it was a proper solution. Other designs include:

1. Having robot enemies follow and scan the player for a period of time before activating the alarm (and then turning all enemies hostile) - perhaps affording the player some extra time or the possibility to avoid a full scan (like in Metal Gear Solid).
2. Having robot enemies not attack the player if they have certain key items that "prove" they are "friendly", like the Power Station red guard's Power Station key 1 or the guard uniform in the Order Commons. This is straightforward enough at a glance but a more elaborate implementation could take into account different key items for different sub-areas (like the multiple Power Station keys) and even introduce new items (maybe as random enemy drops) for any maps that might need them. Once an alarm goes off, all enemies become hostile regardless of these "authorization items" (this is an Id-tech boomer-shooter after all).

It's impossible to know for sure at this point what mechanic the original authors had in mind or for sure if there even was one. However, I still think this would be an improvement to the game as an optional gameplay-enhancement setting for the engine.

I think this is my only complaint about the original game (still one of my favorite games ever) and I always wanted to give it a try once open-source Doom engines became a thing. I haven't got around to yet though and maybe having written this someone else might be inspired to give it a go :D cheers and happy gaming to anyone reading!