Virtual Reality Requires Virtual Presence
The Field of Page and Screen
If you work with a good-sized computer monitor you might have a field of view of forty degrees. For normal TV viewing or a normal page of text, twenty degrees is typical. A very large screen thus fills about four percent of the angular area of the visual stage, and a more typical video screen, movie or book page about one percent, frequently much less. The kind of video we are used to, even the HDTV we might like to have, may truly be called Tunnel Video.
Nailed-Down Desktop vs. Look-Around
Video monitor and TV screens are not only very narrow, they are nailed down. In life we can look around; when we look away from the TV, we don't see stage left, instead, the whole scene disappears. The observable scene as we watch TV is not determined by where we look, but by an invisible cameraman or director. The direction is fixed — quite unlike reality. Video for the amplified life has to let you look where you want to, which is an essential part of moving around as you wish. The required coupling of the display to the direction of the head has been successfully implemented several ways. It is the signature feature of Virtual Reality systems.
Override Your Perception of Reality
To understand the power of a full visual field, we first must understand why even today's modern head-mounted displays typically limit the visual field to roughly 40°. It is because they're still displaying flat images! Imagine experiencing reality with such a limited visual field:
- Imagine that you are in low orbit above Earth looking through a 14" window 14" away from your eye. You will want to press your face against that window to see more. Why? Why isn't the 53 degree central field enough? You can move sideways and up and down and the slow rotation of the vehicle will sooner or later show it all. Why do you have to see it all at once? Why would you much rather be outside, on a space walk, with a transparent globe for a helmet?
- Imagine that you have finally reached the top of Everest (or McKinley, or even Washington) but you must view the scene through a 14" central window attached to your head. All you have to do to see the whole scene is turn around and look up and down. What's wrong with that? Why are you frustrated by the limitation?
- Imagine that you are in a deep sea submersible. The water pressure precludes a larger window so you peer from 6" through a 6" hole. Claustrophobic? Want to just swim out there? Why not just rotate the submersible? What's wrong with that idea?
- And imagine a torrid liaison with your inamorato/a while your view is confined to that same central field.
Something missing?
Recall the last time you traveled from the Great Plains or the southwestern desert to the hill country or the suburbs. Remember how closed-in you felt? Remember how the trees or the houses seemed to encroach on your space, making you a bit tense? It took some adjusting. The peacefulness you lost, which you were not even aware of until it was gone, is the serenity of the Big Sky.
It doesn't take actually trying it, only a certain compression of the mind's eye, to realize how much would be lost at the top of a mountain, or in a ping-pong or football game, if you could only see 40° of your visual field. It would be easy to lose the pleasure of confident jay-walking through the hustle and rush of a New York avenue and the crash and wash of the surf and the far horizons of the open sea that soothe the stroller on the shore. You would be either too preoccupied with the business of swinging your head back and forth, or resigned to not taking it all in.
With careful thought Plato likened our perception of reality to shadows on the wall of a cave, the real world behind the shadows to be perceived only by going outside the cave. The ideal is the unhampered view: The immersive view of reality. Videowrap provides this view. Imagine the power of a view unhampered by the unnatural boundaries of visual limitation.
Don't Use Your Head
In imagining a view unhampered by visual limitation, we may be tempted to take that notion one step further to the conclusion that if we look around just as in reality, we should be able to control our interactions with a simulated world by simply looking around. If an HMD could allow a gamer to aim at targets merely by turning his head, perhaps we would finally be able to throw away our imprecise gamepads and embrace the elegant simplicity of Virtual Reality!
Not quite...
Do you use your head to aim at targets in real life? No? There's a reason. To understand that reason, begin by asking yourself why people don't tape laser pointers to their heads for better control. The answer may surprise you: The human head has poor aim. "Now wait a minute," you may say, "I can just look at my target and shoot it! It's what Superman uses to shoot lasers out of his eyes. How does it get any better than that?" Our answer to you is that looking and turning your head are two very different things.
Try this experiment:
- Look at the corner of your monitor.
- Turn your head while continuing to look at the corner of your monitor.
Your head turned, which would affect your game control in a hypothetical head-aimed game. Your aim would have been constantly moving all over the board, yet during this whole time, you still would have been looking at the same object. So yes, while a look-to-aim system would be superbly precise, it's not even what head tracking provides. Head tracking provides a head-aimed system and head aiming is just a mess. It's what Cyclops uses to shoot lasers out of his eyes when he's not wearing his visor. Don't let anyone try to convince you that using head tracking to aim is natural. It's not.
For a more concrete example, let's consider a real video game. With mouselook, a Quake player can pull an instantaneous 180 degree turn to peg a guy standing behind him. Can your head do that? Unless you're possessed by a demon, your head will not spin all the way around. Even then, it certainly won't turn around instantaneously. The human head has both movement speed and movement range limitations by which video games were not designed to be restricted.
It's not hard to implement head tracking, and once the hardware supports head tracking, it's a trivial matter to bind tracked head movement data to the aiming function within a game. Sometimes, makers of poor-quality head-mounted displays will advertise the ability for you to aim using your head. They do this for one of two reasons:
- They don't understand games and they therefore might not understand why it's a bad thing. (unlikely)
- They don't support any other features of VR and the only way they can integrate their head tracking with existing video games is to bind it to the aim function. They hope that you, the consumer, won't know the difference until after you buy the product. If you haven't thought much about VR, you probably won't.
With an ideal VR interface, you will be able to look around at the environment while piloting a space vehicle or check your blind spots while driving a race car. You will be able to look up, down, and all around. You will be able to point your gun there too. We just recommend you don't use your head.