From the importance of naming things for Virtual Reality

Article by Thomas Balouet @thomasbalou

Virtual Reality is here. It’s almost a granted fact that VR (and Augmented Reality along the way) will be one of those big revolutions which happen every ten years or so:

  • The first Personal Computer in 1975
  • The first Internet Service Providers in the early 1990s
  • The first mass-market mobile phones in the beginning of 2000
  • The first consumer ready VR headset in 2015

And as with every new technology, a new lingo came with the uprise of VR. You might have already heard those words. “Immersive”, “360”, “3D”, “Room-Scale”, “Locomotion system”, “Stereoscopic/Monoscopic videos”… And now you’re like “But I already knew some of these words, so I understand what this technology is about, there’s nothing new under the sun”. Well, you are right, those words are not new, but people are using them for a new meaning, and that’s where the problem is.

One word, different meanings

On this article, I’d like to focus on the representation of VR, and in what it differs from the former numeric experiences you might have had. Let’s start with the “3D”, and what it really means.

Three-dimensional space

This is a geometric setting in which three values are required to determine the position of an element (i.e., point). This is the informal meaning of the term dimension.

It allows to determine a position in space, and also to move things in this space on 3 different levels. Let’s take the example of video-games, where 3D allowed for a much richer game-play, from that:

Super Mario World for SNES

To that:

Super Mario 3D world for Wii U

But the 3D is already also applied to other environments, like the cinema or your TV. The common aspect in all that is that it let your brain perceive depth. But your brain is not that smart, and if I want to trick it, I can make a 2D image look like it has depth too, like this:

No 3D glass required here ;)

All it took was adding two white stripes and play with it. So using the word 3D became too imprecise, as it only truly mean “which renders depth perception”, and has many ways of realizing that. So speaking of 3D for VR is true and at the same time might sound a bit useless and confusing.

Different kind of VR?

When it comes to VR, at this moment, we can differentiate two main types of experiences: the 360 ones, and the others.

360 movies and experiments

3-degrees of freedom

In a 360 experiment, you can look all around you (at 360 degrees), but you cannot move your head inside the experiment. You are a still point and all you can do is contained in what’s called the 3-degrees of freedom: roll, yaw and pitch.

Looks like the same image twice, but it isn’t. That’s a side by side stereoscopic video

And guess what? These experiments are made with 3D graphics (the content is rendered on a sphere by example). But is it 3D? 360 videos can be monoscopic when they are filmed with most of the actual cameras, so the depth perception is very difficult. Some cameras like the Nokia OZO allow for stereoscopic filming, which means it’s like if each of your eyes were recording a different film, instead of just your nose. So rendering each film for each matching eye give a better depth perception than applying the same film on both eyes.

What you lack there is the ability to move your head up/down, left/right and forward/backward. That would give you the “6-degrees of freedom” (also called 6dof) which are necessary to enable immersion.

Here, I did it, another VR-related word! And that’s one of the most important ones, along with “presence”. It is the feeling that every company tries to create in their experience, and which will allow the user to truly “feel there”, and trick his brain in forgetting that he’s wearing an headset.

The concept of immersion didn’t appear recently and it came at least from the early beginnings of VR researches 20 years ago. True immersion depends on different factors, mainly being able to replicate real life movement into virtual space with 6dof, being able to interact with the environment and get logical feedback, get some real social interaction and get a positional audio to really be able to locate objects in space. If you want to know more about it, I encourage you to watch this very well made video.

The other kind of experiences

So what are the “non 360” experiments? In order to access those experiments, mainly we’ll go in the direction of more sophisticated headsets, like the Oculus Rift and HTC Vive, which allow 6dof by having captors who can tell where the headset is located in the space (its 3D position). Those headsets are also equipped with (or will very soon be) controllers, allowing the user to simulate his hands in the experience, and therefore be more immersed as he can interact with his environment.

In this kind of configuration we can experience feelings of presence, and have really interesting feelings caused by the application. That’s what every VR creator is looking for.

So is VR 3D? And what is VR?

We’ve reached the $1 million question. Nobody knows and everybody has his own answer. Some people will say that 360 experiments are not VR, because of the lack of movement (and don’t even talk to them about monoscopic!). Some say no experience will be true VR before you can wear an haptic suit allowing you to track your full body in the virtual environment, and to receive direct feedback from it.

So yes, VR IS (composed with) 3D, but it doesn’t resume to that. And a lot of very different things are using 3D, so maybe we should stop using this “unsubstantial” word for descriptions which is not really helping to explain what VR truly is. As for 360 monoscopic vs stereoscopic vs the rest (which you could call, sic, “real time 3D”), if it’s real VR or not real VR, that’s difficult to say because the definition of VR itself isn’t absolutely clear. And a lot of debate are about this question.

So I think that all VR creators that we are should stop and take some time to define and have some clean explanations on this new technology, before trying to bring it further. It will help the consumer understand what we want to make him try, and stop the ongoing useless debates…

Or maybe we could just say “Try that thing I made, it’s magical, don’t ask what it’s about, just go!”…