[imtringued]

I don't understand how you can use stealth as an example. The only way you can fairly simulate stealth mechanics is by making every enemy render the scene at low complexity and then check if it can see pixels of the player model. Maybe some games do this but from my experience what happens when you get caught is pretty boring. They sound the alarm and they all hunt you down as if they had a radar because actually doing the simulation is too expensive. There is no need for a third state. Once the alarm is on it is on but it shouldn't mean the enemy knows where you are.