You could reproduce the Minority Report computer interface today, provided you were willing to don a special pair of gloves, don a special pair of glasses, and stand inside a specific area to use it. It would just be ¢o$tly.
Have someone manufacture a piece of polycarbonate sheeting, about a meter and a half from top to bottom, as long as and curved to fit a 45° chord of a circle perhaps 3 meters in radius.
At the center point of that circle, draw a 1/2-meter circle on the floor, concentric with the larger circle. From the ceiling above the circle's center point, suspend a projection TV system. Modify the optics of the projection screen TV to project onto a curved rather than a flat surface.
You then put on a pair of gloves that provide to the computer the positions of your fingers and tell the computer where in 3-space your hands are.
You then put on a pair of glasses that tell the computer where in 3-space your head it and what direction your head is facing. The glasses will also have low-power lasers to detect where your eyes are pointing.
The computer projects the user interface graphics onto the polycarbonate screen. The glasses tell the computer where you're looking. The gloves tell the computer what you're going with your hands and where you're doing it.
Throw some programmable digital signal processors or programmable gate arrays at calculating all the parallaxes involved, and it's just a matter of writing the the software to actually manipulate the UI.
The only part of the system that isn't commonly available is the head and hand position systems. The head point system is available, but it's military technology and might be classified. But similar things to what our UI needs are used on the Apache and Comanche helicopters for their chain gun aiming systems.
The looking-point system is used for UIs for people who can't manipulate a mouse, such as quadriplegics. I don't know one way or the other, but the Comanche reticle systems may have that technology already built in.
The gloves are available -- I've seen them used in computer labs. Although they're not necessarily off-the shelf, it shouldn't be too hard to find someone who could produce you a pair.
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