Monday, March 27, 2017

Virtual Reality Standards: too early or long overdue?

This article originally appeared on Mar 22nd at ReadWrite
You bought a new printer for the office. You unpack and connect it to your PC. You install its demonstration software and see the printer works well. Then, an unfortunate surprise: your word processor cannot work with this printer. You'll need to wait until the maker of the word processor releases a new version. When will this version be available? Should you return the printer? Should you change to a different word processor?

If this sounds like the 1980's, it's not too far from where VR is today. VR programs are often hard-coded to one set of hardware devices. Only a particular HMD, coupled with its tracking system and controller will work. Every device manufacturer has a different API. If you want to use this VR experience with a different set of hardware, you might not be in luck. At best, you'll need another version. Worst case, you just won't be able to do it. The problem of different vendors having different APIs is often called 'API fragmentation'

VR standards can help solve this fragmentation problem. In the PC world there are a few basic device types: keyboard, mouse, printer, scanner, and so forth. Likewise, basic VR device types include an HMD, tracker, controller, and a few others. A standard way for a program to interface with these VR devices would help solve this problem.

If software could work across different hardware combinations, almost everyone would benefit:
  • Consumers could mix and match devices to their liking. I may have a Dell computer but I don't always want a Dell printer to go with it. Furthermore, consumers would be confident that their investments are future-proof. A 2017 game would likely work with 2018 or 2019 hardware. 
  • Game publishers and other experience creators would have a larger addressable market. Today, they hard-code their game to a particular set of hardware devices. Tomorrow, they would support any device that has a conforming 'driver'. 
  • Manufacturers that support a standard would have their devices work with lots of content. This would allow even small players to enter the market, and promote innovation. 
Some claim it is too early for a VR standard. VR is new, they say. Let a couple of years pass and then we will know what to standardize. Yet while consumer VR is new, VR has been in academia and industry for decades. Labs and factories deployed HMDs, head and eye trackers, and controllers for many years. Such devices were expensive and perhaps more clunky, but still performed the same functions. Software frameworks like UNC's VRPN ( provided device independent access for many years.

The resistance to a standard sometimes stems from the competitive strategy of a company. A vendor relying on a 'walled garden' approach often wishes to control the entire stack. The ability to swap out hardware, or use a different app store might be not what they had in mind.

In VR, there are often two standard interfaces that need to defined. The first is the device interface. This defines how to configure devices of particular type and how to extract data from them. Printers have different capabilities but share the same basic functions. The same is true for VR devices. The second standard interface is the application interface. It describes how an application or a game engine renders its content and get data. Inbetween the applications and devices there is often a middleware layer. That middleware is the software intermediary between applications and devices.

One effort that adapts this approach is OSVR. Started by Sensics and Razer, it is an open-source software platform for VR. OSVR implements both a device interface layer as well as an application layer. OSVR supports over 200 devices, and most of the OSVR code is free and open-source.

Another effort is OpenVR which is an open API (though not open source) from Valve. Building on the success of SteamVR, OpenVR allows HMDs to work with SteamVR content. There is some compatibility between these efforts. An OSVR plugin for OpenVR, allowing OSVr devices to work with SteamVR content.

In January, the Khronos group (known for OpenGL standards) launched a new VR initiative. The initiative, called OpenXR, brings together a wide range of companies. Industry leaders including Google, Oculus, Valve, Sensics and Samsung are part of this effort. OpenXR aims to combine lessons learned from building OSVR, OpenVR and proprietary APIs. It aims to create both a device interface as well as application interface. It is unclear how soon this effort will mature. Khronos standards take an average of 18 months. It is also unclear what capabilities will be part of the first standard. What is clear is that these companies felt enough pain to want to work on standards.

I am encouraged that so many participants are coming together to work on a standard. Other interested parties are also invited to contribute. Standards are sometimes boring, but they are important. They will make the consumer experience better and promote innovation.
This article originally appeared on Mar 22nd at ReadWrite