This is probably the easiest way to simulate vision. We take a collider, be it a mesh or a Unity primitive, and use it as the tool for determining whether or not an object is inside the agent's vision range.
The seeing function using a collider-based system
Getting ready
It's important to have a collider component attached to the same game object using the script in this recipe, as well as the other collider-based algorithms in this chapter. In this case, it's recommended that the collider is a pyramid-based one in order to simulate a vision cone. The fewer the polygons, the faster it will be in the game.
