Answer Wiki. The system would be cued off the pilot's helmet, so it will definitely look where your head is pointing, not your eyes specifically (that would be a gaze-tracking system, which AFAIK hasn't yet been used for this kind of application).
Exercise to Gain Leg Weight. Although you can't make your body gain weight in your legs, you can perform exercises that encourage the growth of leg muscle. Squats, lunges and step-ups are examples of such moves that target the legs and recruit a lot of muscle fibers for growth.
It's All About the Calories. To slim your legs and reduce fat, lose no more than two pounds per week by creating a daily caloric deficit of 1,000 calories. Although it might be tempting to severely cut calories to see quick results, drastic measures are hard to maintain in the long run.