Well, better as front-faces, the capability to focus on a point in front, since a 3D vision is essential for a predator, to be able to accurately calculate distances. Insects and arthropods often combine side and frontal vision, if they are predators, obtaining a vision in practically 360º, for example dragonflies and also jumping spiders or hunters, these usually have two large eyes in front and 6 smaller side eyes. Chameleons solve this with eyes that can move independently, only focusing on the front before the attack. In small animals a wide field of vision is necessary, even if they are predators, since they themselves appear on the menu of others.