Virtual Reality – a peek behind the wizard’s curtain
Just as Dorothy Gale was blown away into an alternative reality on that fateful day in Kansas, we too stand at the precipice of a technological tornado. Virtual Reality is now the hottest topic in the tech world gathering momentum, key tech giants and an army of content developers all promising to whisk you away to the outer limits of your imagination.
But where did this technological twister originate from? What magical powers fool our mind into believing we are in fact standing on another planet or stroking the back of a giant whale? Let’s pull back the Wizard’s curtain and take a closer glimpse at the technologies that make this magic happen.
Currently the key immersive factor in VR is what’s being displayed in front of our eyes.
Although research is underway to allow us to hear accurately positioned spatial sound, give our sense of touch the ability to feel a surface or object through haptic feedback and even early attempts are being seen into stimulating our senses of smell & taste, VR in its current iteration relies almost exclusively on visual stimulation.
And this visual stimulation is achieved by a stereoscopic image being displayed on a mobile phone screen. Yes, that’s what it boils down to. If you crack open an Oculus Rift or an HTC Vive what you will find at its core is an overclocked mobile phone screen, and of course if you have experienced either the GearVR or Google Cardboard you are aware what’s being inserted into these empty headsets are nothing more than a mobile phone. Mobile phone screen technology in the last ten years has evolved from displaying blocky barely readable text to today’s HD 4K resolution quality, which in non-technobabble means crystal clear images and videos for you to enjoy right on your mobile phone.
VR allows the user to freely move their head around to explore their environment just like they would in the real world
VR takes full advantage of these ever improving screen technologies to render 3D environments right in front of your eyes. But unlike a 3D movie at a cinema which renders everything on one wall, VR allows the user to freely move their head around to explore their environment just like they would in the real world. A system called ‘Six Degrees of Freedom’ checks every fraction of a second where your head is in a 3D space measuring your X, Y, Z and rotation. It manages to achieve this with a combination of gyroscopes, accelerometers, magnetometers which all work together to accurately plot your head in the digital world. These systems work in unison to ensure that when you move your head what you are seeing on the display is updated in less than 20 milliseconds, which is fast enough to fool your brain into seeing motion.
Currently computer processors are not powerful enough to render a complete 360 environment every frame so VR software quite cleverly checks where the user is moving their head, calculates the speed, and then predicts where the user is likely to stop. It then casually renders just that part of the 3D world.
Best experienced with native input devices
Building on tracking your head is the ability to track your hands in a virtual world. Virtual Reality is best experienced with native input devices, which mean throwing the keyboard and mouse out the window and using your hands or a set of hand devices that allow you to more naturally interact inside a virtual environment. These input devices in their current iterations are small controllers that you hold in each hand but we will very quickly see the ability to simply track your real hands in VR.
Each headset has their own technology for tracking their respective input devices from tracking a light source on the controller with a camera such as with the PlaystationVR to using a sweeping laser system such as with the HTC Vive. These solutions allow the ability to track an object such as the controller within 1mm of accuracy giving super precise movement of your hands in VR.
These three systems; visual displays, head tracking & native input all come together to give a user an immersive and believable experience. Its worth noting that there are a number of other emerging technologies that will help augment the immersion of the user into VR, including eye tracking, hand tracking, haptic feedback as well as binaural headphones and we should see these emerge onto the VR scene over the next 2 – 3 years.
So next time you don a VR headset, give an appreciate nod to the immense technological and programming prowess which lies just behind the Wizard’s curtain of virtual reality.