While developing Embody, I realized the eye tracking module could be useful for any mocap animation, where the head is controlled, so I made a dedicated plugin for this. In this plugin, the head direction determines objects that can be looked at within a frustrum (field of view), and the eyes will look at them randomly. I also added an eye saccade mechanism, which will make a huge difference in making the eyes believable.
You can select which object(s) should the person be allowed to look at, for example the camera, the player, hands, objects in the scene, etc.
Here's an example of the Glance system used with Embody's Leap Motion: https://youtu.be/SFk56NnGhmY
Download Glance: https://www.patreon.com/posts/49174532
Download Demo Scene: https://www.patreon.com/posts/49174919