Determines whether entity 2 is visible from entity 1. @param posFirst position of first entity @param facingFirst direction first entity is facing @param fovFirst field of view (radians) @param posSecond position of second entity @return true if second entity is inside 'visible' to the first entity
(final Vector2D posFirst, final Vector2D facingFirst, final double fovFirst, final Vector2D posSecond)