Right now, it seems sight is simply based on distance+LOS.
I thought we should add a chance of noticing monsters and of monsters noticing characters even within that range, based on the following conditions making them harder to notice:
Creature’s stealth modifier
Further away
On a hazard square (Bush, small tree, rubble, cars, water, pit)
Behind some hazard or obstacle square (the above, plus tables, benches, counters, etc.)
Not moved recently (this could be simple as having a “motion” tracking variable that ranges from 0-10, decrements each turn by 1 and increases by 3 every time you move, so even moving slower is more stealthy)
Near a wall or obstacle (up to three spaces from a wall. A creature in the middle of an empty field is easier to spot than one in an alleyway, since it sticks out more)
In addition to this change, I’d also make the following map change suggestions:
Tall Grass - Very frequent in Field Squares, tall grass obscures sight.