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Decoupling of Aim and Gaze in Virtual Reality Systems

Summary: When wearing a headset, there's no reason your target should be aimed the same direction that your head is facing.

The recent Errant Signal video “Inputs and the Rift” makes a very good point about virtual reality games where you have a weapon, or target, that you are shooting.

With a traditional game for PC or game box, where input is given with a keyboard or a controller, your body, your aim and your gaze are all facing exactly the same direction. When you signal you would like to turn, all three of your body, your aim, and your gaze move.

This is a limitation caused by only being able to see your game on a monitor. No matter which way you turn in the game, your TV is still in the same position relative to your head on the couch. You could separate aim from gaze, but you’d need two sets of directional inputs. Most people only have two hands, so turning both aim and gaze to face a new enemy would require both of your hands and remove your ability to shoot (at least, shoot intuitively). This method of input also has a steep learning curve, a kiss of death for most games.

With a VR headset turning your gaze is natural and controlled by the natural movement of your head. This frees up your hand to control your aim direction, and your other hand to fire the trigger, or maybe an input would be designed that allows you to do both, the same way you would fire a gun in real life. This is a nice and natural consequence of having a screen that follows any direction you can turn your head.

The converse is also true: Having your aim follow your gaze with a virtual reality headset is awkward. Imagine walking around in real life with a gun that changed position every time you moved your head. It’s weird and another reason why porting games from other systems will be challenging.

What changes does this imply? We may see more visual stimulus coming from off-screen directions, taking advantage of the decoupling present to require more vigilance from the player. Currently it is extraordinarily rare for your character to be attacked from behind, even if a real life enemy force wouldn’t be so stupid as to only attack from one direction. On the other hand, the experience of being frightened or shocked if attacked from behind could be much worse with a VR headset, leading to fewer attacks from directions you’re not facing, or at least, requiring a warning system (sound, or a heads-up-display, or something).

This decoupling also means that the input we use to control aim are probably going to change. Controlling your aim by moving a joystick, when you can change your view by moving your head, seems unpalatable. It’s not clear at this point what a great input looks like.

I’ll update this post soon with examples of games that get this right, as well as games that get this wrong. In a future post, we’ll survey the available input devices on the market, and get a sense for how maps and bad guys are changing in our new virtual reality world.