I'm thinking of stealth games where an object has a certain field of view that you want to avoid otherwise game over.
The field of view may be linear or circular or any arbitrary group of pixels/tiles.
If I don't consider obstacles (for example, if you're standing behind a wall, they can still see you), I can determine whether the player is within an object's field of view using simple geometric properties using the two object's positions and range. This can be done efficiently, though it kind of assumes the objects are points.
However, to make it realistic, you should be able to hide behind a wall or a tree without being seen.
How is this problem usually solved?
What are some articles that I can read to understand more about this problem?