Qualcomm Snapdragon 845 Mobile VR Reference Design Includes Roomscale Tracking

There is a bit of a craze going on with standalone virtual and augmented reality headsets, thanks to the rapid development afforded by Qualcomm’s VR reference designs that now date back a couple of generations. Today, ahead of the Mobile Word Congress event, Qualcomm is unveiling details of its latest reference design, which now includes the updated Snapdragon 845 Mobile VR SoC.

We saw a glimpse of some of the design changes to the new reference head mounted displays (HMD) back at the Snapdragon Tech Summit, with the announcement of the Snapdragon 845 SoC that’s to be used in next-gen flagship mobiles. The Mobile VR extension is purpose-built for Xtended Reality (XR) headsets which are used by other companies to build standalone headsets.

We’ve already seen a number of these reference designs being put to use by the likes of Lenovo with its Mirage, and HTC with the standalone Vive Focus, even Oculus, each built around the Google Daydream concept. The new reference Mobile VR design is the usual mix of faster processing and more power efficiency, but with a couple extra features thrown in.

The new reference is very similar to the previous iterations in terms of physical appearance, it’s a typical HMD with a large screen with optics and two cameras in the front. Those cameras are what provide the augmented aspect to the virtual one for Xtended Reality. The two cameras do have an additional function as they power the new SLAM feature, Simultaneous Localization and Mapping, or put another way, roomscale environment mapping for full 6-degrees of freedom (6DoF).

The previous generations were limited to 3DoF, which translates to just viewing (yaw, pitch and roll), 6DoF effectively allows for forward and back, plus up/down side-to-side tracking, meaning you can freely move around a room, without the need for external sensors (such as with the current desktop HMD units from HTC and Oculus), as it’s all handled by the two cameras building a map of the room (you can see a rough approximation oh how this is done from a previous news post about Qualcomm’s Spectra ISP and its 3D mapping).

Another feature relates to eye-tracking, and is for something called foveation rendering. This is something that a number of tech companies have experimented with for the last couple years (you can see an example of this here). It’s a method of more efficient rendering by taking advantage of the fact that our eyes do not see the world perfectly like cameras do. Instead, the GPU will only render the highest details based on where we are looking, and use less detail outside our direct field of view, which to our eyes appears blurred.

This method takes advantage of our own brain’s capabilities to build a full mental image of a scene, based on the small area that our eyes see in detail. From the headset’s standpoint, it means processing saved in the low-detail sections can be used to make more realistic renders in the parts we can see, increasing the overall image quality. This is something that’s been part of the standalone sets since the Snapdragon VR820, but it’s taking a while to use effectively due to the need for accurate eye-tracking.

Since Snapdragon 835 Mobile VR headsets have only just started coming out since CES 2018, it’ll be a few months yet before we see the new 845 Mobile VR SoC being put to use, however, even early indications of the previous gen have been pretty good, but it’s that 6DoF from the 845 that will push standalone VR headsets forward.