The term “virtual reality” is actually a rather broad concept, describing a collection of presentation mechanisms to trick our brain into a sense of presence within a virtualized environment. At its most basic, this probably includes a separate image for the left and right eye, which creates a sense of depth, and rotational tracking so as you move your head, the images change appropriately. And, indeed, all VR products on the market have these features in common. But that’s where the commonalities end.
Only a few devices allow for positional tracking, in which images change based on your movements as you move your head forward or back (or walk forward or back). This is a huge help in creating that sense of presence, and reducing “VR sickness,” but can be technically challenging and requires a more complex setup. VR devices may or may not have features like low latency, high frame rates, differing resolutions, and other minor features that differ among implementations.
Most of these “viewing” differences can be handled for content creators by the software they use to create VR experiences. Sure, if you design an experience that allows a user to walk around a physical room and experience things in a virtual world (as the HTC Vive allows), it’ll be difficult to port that experience to a device that does not have the same tracking, but it’s not impossible in a technical sense. The issue is more one of user experience and interaction.
And therein lies the rub.
User input is going to be the thorn in VR’s side for at least the next five years. How we can best see a virtual world has been mostly figured out by the top VR devices (there’s still room to grow in processing power and resolution, but the product pathway is extremely clear). But how we can best interact with a virtual world is anyone’s guess.
There are multiple versions of touch controllers (controllers held in the hand that can emulate grabbing and natural hand rotations and movement). There are omnidirectional treadmills that can allow “walking” in a virtual landscape. Experiments are under way for devices that can create kinetic “feedback” for interactions with a virtual world, so that there’s a true sense of touch. And each of these concepts has multiple vendors working on their own specialized version. it's all fragmented -- a fact that's ugly, and not going away any time soon.
What this means is that while passive VR experiences (a virtual movie theater, a VR opera, a zoo for alien creatures, or VR porn) can rather easily be ported between all the different VR solutions (for example, HTC Vive, Facebook’s Oculus Rift, Google Cardboard, Samsung’s Gear VR, Google’s upcoming Daydream), an interactive experience has extremely limited portability without a great deal of work between devices -- each of which will, for the near future, lack enough market share individually to drive the revenues needed to attract content creators.
Basically, as long as VR resists the pull of standardization among companies desperately trying to differentiate themselves from each other, nobody wins, and quality VR content will be scarce.
VR reaction of the week (caution: NSFW language):