Eye tracking support is coming to the HTC Vive - here's what you should know!

Following the release of several high-end VR headsets, hardware manufacturers are beginning to search for the "next big thing" in virtual reality. While wireless VR and improved visual fidelity are seeing heavy investment, various new technologies are emerging which promise to deliver a more immersive experience. Enhanced tracking is one of these areas of interest, in an attempt to further bridge the gap between your physical body and the virtual world.

Eye tracking looks to be one of the more interesting technologies, potentially offering huge leaps in immersion and performance. With companies like "FOVE" taking orders for VR headset sporting full eye tracking, we're already beginning to see small companies push for technology. But what if you could use eye tracking on your existing VR hardware?

Updated June 7, 2017: We've refreshed this guide with details on Tobii eye tracking, which promises a similar but integrated solution for the HTC Vive.

Enter the aGlass

With FOVE still a few months off shipping the first version of its headset, a new Chinese startup, 7invensun, has begun to draw attention to eye tracking once again. With its upcoming product, "aGlass," the company is preparing to offer a third-party eye-tracking module for all existing HTC Vive headsets.

The aGlass is comprised of two external lenses, which sit above the HTC Vive's existing lenses. These plastic overlays are fitted out with an array of infra-red lights and sensors, which aim to track both eye and eyelid movement. This makes for a modular "plug-and-play" solution, which hooks directly up to the headset through its USB port.

Although we're yet to get our hands on the product, 7invensun promises both accurate eye tracking and low latency from the aGlass. As stated on the company's website, the trackers offer precision to less than 0.5 degrees and latency below 5ms. If the product lives up to these claims, this should offer a seemingly 1-to-1 translation of your eye movements in most scenarios.

To overcome the issue of interference from glasses, custom aGlass lenses will also be available on request. The company is already offering 200, 400 and 600-degree myopic lenses for developers for no additional cost. These lenses can be switched on the fly, which prevents the tracker from being tied down to a certain individual.

Tobii Eye Tracking

Tobii is a Swedish company that has already established roots in eye-tracking, with existing solutions for assistive technologies, research, and desktop gaming. The firm most recently expanded into the virtual reality space and is already taking orders for eye-tracking development kits, which lay the foundation for endeavors.

In contrast to the aGlass' simple plug-and-play nature, Tobii's eye tracking VR dev kit is an all-in-solution built into the "HTC Vive Business Edition". With a "Tobii EyeChip" SoC (System on Chip) integrated directly into the headset, its eye tracking technology is managed independently from the headset, via the additional processing capabilities.

When it comes to tracking, Tobii's solution leverages infrared sensors lined around the inside of the lenses. Although the technology isn't too different from what powers aGlass, this is an inbuilt solution developed specifically inside an HTC Vive headset.

While Tobii isn't offering a consumer-focused solution right now, its recognized eye-tracking technologies make this a promising solution. Even if "7invensun" is currently guaranteeing a much more accessible solution, it's yet to be proven how the aGlass performs.

What to expect from eye tracking

Although we're yet to see many instances of games that support eye tracking, various uses have already been pitched by manufacturers. However, we can expect to see further innovation once the product gets into the hands of more developers.

Primarily, eye tracking can have a huge effect on performance, with the assist of a technique known as "foveated rendering." By tracking the positioning of your eyes, games can be rendered based on your line of sight. This allows your PC to only render certain parts of an image in full detail, with objects in your peripheral vision rendered at a lower resolution.

An example of foveated rendering in action, as demonstrated on SensoMotoric Instruments' eye tracking platform.

With this more efficient way of display images in virtual reality, this could theoretically, this could lower the entry point for VR hardware. with a less load dropped on your PC. 7invensun has clarified that out of the box, foveated rendering will be supported with NVIDIA hardware, using bundled in-house software.

Eye tracking can also influence gameplay, by adding an additional method of input for VR experiences. By tracking eyes it's possible to capture a new level of player emotion, which could hugely affect social experiences offered in virtual reality. This tracking could also extend to gameplay-driven experiences, with a game dynamically adapting to your eye positioning.

How can I get started with eye tracking?

The first batch of aGlass units will be shipping from China later in May, available as a part of a limited run of pre-orders for $220. The company has also promised to deliver wider rollouts during the later half of this year, including plans for a western release. Hopefully, by the time the product is more generally available, numerous developers will have jumped onboard.

As for Tobii – only requests for its initial eye-tracking development kits are currently being accepted. Although the company isn't accepting pre-orders for any consumer-facing accessories, we'll be sure to update this post once more information surfaces.