The following diagram shows how the two-step vision system works:
The collider component checks every frame to see whether it is colliding with any game object in the scene. We leverage the optimizations in Unity's scene graph and engine, and focus only on how to handle the valid collisions.
After checking this, if a target object is inside the vision range represented by the collider, we cast a ray in order to check whether it is really visible or whether there is a wall between the target and the agent.
