Ask GadgetGuy: how does VR actually work?

Virtual reality is coming, with Facebook’s Oculus, HTC’s Vive, and Samsung and Sony getting in for people without computers, but what is it really, and how does it work?

There’s something coming to your home, and it has the potential to change how we learn and how we see the world. It’s a gadget that can change entertainment and education and blend it all so it becomes one, immersing you — the individual — into the frame in a way that makes it seem as if the future has arrived.

And in a way, it has.

It’s called “virtual reality” or “VR” for short, and it’s the sort of thing that fuels science fiction.


Built as a headset, you have to think of it like a pair of 3D googles, only it’s a very advanced pair of 3D glasses with a pair of screens and a few sensors to track your positional space.

More on that later, though, because we need to tackle that whole 3D thing first, because VR and 3D have a lot in common.

Four sets of these glasses are thrown in the box.

When you watch a 3D movie, you’re seeing two sets of images on the screen: one for each eye, left and right.

The glasses you watch 3D movies with at the cinema have two types of lenses that enable this, with your left eye seeing the A lens and the right eye seeing the B lens.

Each of these lenses can only pick up on the one set of frames, which is why if you take your glasses off, the frames overlap and it looks blurry.

In truth, you’re actually seeing two sets of frames at the one time, and your brain cannot push these together, so we do this with glasses which let you see each frame individually just as your eyes would, with your brain merging the angles and doing the math for you.

It’s also worth noting that the way the frames are setup, you can’t put the glasses on backwards to see the frames.

Doing so would put the right eye lens on your left eye and the left eye lens on your right, and then you’d be seeing things overlapping in a way that could be jarring, like two competing images fighting for prominence.

So don’t do that, as your brain will hurt.

For now, let’s talk 3D.


When something is made for 3D, you’re essentially seeing two cameras. In a 3D movie, that’s a camera rig setup for the positioning between a left and a right eye, while computer animated movies and post-processed movies into 3D (and there are a lot of these) rely on computer-based 3D rigs.

These rigs emulate the position our eyes take, which is why each lens is technically seeing a different part of a 3D move: the lens on the left sees more of the left, while the lens on the right sees more of the right, sort of like what happens when you take in the scene in front of you — anywhere really — and close one eye at a time.

Close your left eye and you see a little more on the right. Close your right eye, and you see a little more on the left. Leave both eyes open and you take in the entire scene.

That’s 3D, and the depth behind 3D is explained by distance. The further the distance, the less pronounced the depth, but the closer it comes to you, the more an object is reaching to you, though this can be engineered in films and video games (and often is).

Virtual reality is like 3D, but a little different again.


Imagine a scene where you’re seeing the entire world around you, not just a set of pre-recorded images that move in front of you.

A 3D movie is a pre-recorded movie set up as one specific point of view, usually controlled by a director, be it from a movie or a game.


In virtual reality, however, the scene you see isn’t necessarily set, and you can shift your position by moving your head.

Turn your left from left to right and the view will change, realigning your view with that of the world, often with the depth from 3D.

VR is therefore like 3D, but wider and more open. It often encompasses the depth needed for 3D, but doesn’t have to.

3D VR offers the world of virtual reality and the depth of 3D by delivering a 360 degree surrounding for two lenses, left and right. The best of both worlds!
3D VR offers the world of virtual reality and the depth of 3D by delivering a 360 degree surrounding for two lenses, left and right. The best of both worlds!

What it does have to do is provide a total plane, allowing you to look 360 degrees on the horizontal view — the standard head turning you can do — and sometimes the remaining 360 degrees of verticals.

Most VR movies don’t do the full limit of verticals, hence why we say “sometimes” with that, with the typical VR movie only focusing on a bit of the bottom and the extent of the top, the latter of which is often the sky or a ceiling.


But VR is about the world around you, or more specifically about worlds around you. Our world is distinct from “worlds”, because while it could be real life 360 degree footage you end up watching in virtual reality, it could also be a far off land, a made up place, or even space.

Essentially, anything you’ve ever seen a movie of or even played a game of can become a virtual environment provided it’s been made for VR.

That’s the entertainment world you have to look for, and it will change the way we see things.

And now you know how it works.