Immersing yourself in a virtual world has long been a dream of science-fiction stories - and it's about to become a reality. We take a look at how this amazing technology works, who the main players are, and how it's going to change the future of computer graphics.
What is VR?
Virtual reality - AKA VR - is a medium for viewing and interacting with 3D content. It's been around since the early 90s, but it has its roots in stereoscopic viewer toys, such as View-Master, which were invented in the 1930s.
How does it work?
A couple of screens - one for each eye - are embedded in a VR headset. These display slightly different angles of the same scene. Your brain merges these two 2D images into one 3D scene.
That sounds incredibly simple. Surely there's more to it than that?
Well yes, it is a mite more complicated. The person wearing the headset has to be able to look and move around the scene, and to do this the headset must be able to track their head movements, then update the image on the screens accordingly. And it has to do this many times every second - this is referred to as latency.
Why is everyone suddenly interested in VR again?
The resurgence of VR was spurred on by the Oculus Rift. Developed as a prototype by University of Southern California student Palmer Luckey, it caught the attention of games industry legend John Carmack, the man behind Doom and Quake. Luckey began a crowdfunded Kickstarter campaign for the Rift, which ultimately raised $2.5 million for the development of the device.
What does the Oculus Rift do differently?
In the 90s, VR headsets were big, heavy devices which displayed rudimentary graphics. The Rift prototype makes use of miniaturised tech - much of it cribbed from smartphones - to do the necessary calculations in a small, lightweight unit. It also uses a gaming PC's graphics chip to do the heavy graphical lifting.
Who are the other main players?
The Rift caused a ripple, and other companies jumped on the VR bandwagon. Samsung and HTC collaborated with Oculus to produce the Gear VR and Vive, respectively. Sony's PlayStation VR (formerly Project Morpheus) and Microsoft's HoloLens are both up and coming, while anyone with a smartphone can make use of Google's Cardboard right now.
What are they doing differently?
As VR is becoming a flooded market, the various manufacturers need to differentiate themselves. HTC's Vive includes motion sensors, which mean you can move around a room and it'll work out your position. HoloLens, meanwhile, projects 3D objects into the space around you, so you can potentially build a virtual Minecraft world on your real coffee table.
What are VR's uses?
Gaming and VR go hand-in-hand. The real-time graphics engines which power video games are well-suited to headsets, and a lot of the big players have already implemented VR support.
There are hundreds of other uses for VR, though, from entertainment (there have been tie-in VR experiences for Game of Thrones and Sleepy Hollow), to architectural visualization, to medical imaging, to post-traumatic stress disorder (PTSD) treatments.
There are certain limits to VR, though, and most of these relate to the comfort of the headsets. They have to be light enough to wear for extended periods, but they also need screens with high resolutions and refresh rates so they don't induce headaches and nausea. However, VR manufacturers believe they've solved these problems.
How will it change things?
If VR takes off we're going to have to approach conventional media very differently. Remember, when you're in a VR world you can look up, down, left and right, so a full 360-degree environment has to be created around you.
Conventional storytelling techniques, such as cuts between scenes and shots, won't work, and you can't draw someone's attention to an object with a close-up, for example. Instead, you'll have to build a smooth and seamless 3D world in which to tell your story. This is another area where games have an advantage - Half-Life pioneered this approach to storytelling almost 20 years ago.
When can I get my hands on a VR headset?
The only headsets available at the moment require a smartphone to provide the display - and this includes Samsung's Galaxy VR, which requires a Samsung handset. It's all set to change early next year, though, when the Oculus Rift, HTC Vive, PlayStation VR and Microsoft Hololens are due for release.