The Khronos Group of Beaverton, Ore., an open consortium of leading hardware and software companies that come together to create advanced acceleration standards, has released the OpenXR 0.90 provisional specification. OpenXR is a unifying, royalty-free, open standard that provides high-performance access to augmented reality (AR) and virtual reality (VR)— collectively known as XR—platforms and devices.

The new specification can be found on the Khronos website and is released in provisional form to enable developers and implementers to provide feedback at the OpenXR forum.

The OpenXR 0.90 provisional release specifies a cross-platform application programming interface (API) that enables XR hardware platform vendors to expose the functionality of their runtime systems. By accessing a common set of objects and functions corresponding to application lifecycle, rendering, tracking, frame timing, and input, which are frustratingly different across existing vendor-specific APIs, software developers can run their applications across multiple XR systems with minimal porting effort—significantly reducing industry fragmentation, said Brent Insko, lead VR architect at Intel and the OpenXR working group chair.

The Khronos OpenXR working group was formed in early 2017 with the support and participation of leading XR companies. Throughout the development of the specification, multiple Khronos members have been developing independent implementations to ensure a robust and complete specification. Many of these implementations are becoming available for developers to evaluate including the Monado OpenXR open source implementation from Collabora, and the OpenXR runtime for Windows mixed reality headsets from Microsoft. Also, the Unreal Engine from Epic plans to continue to support OpenXR.

“OpenXR seeks to simplify AR/VR software development, enabling applications to reach a wider array of hardware platforms without having to port or re-write their code and subsequently allowing platform vendors supporting OpenXR access to more applications,” Insko said “The OpenXR provisional specification—together with the runtimes publicly available at launch and coming in the next few weeks—will enable hands-on, cross-platform testing by application and engine developers.

“The working group welcomes developer feedback to ensure an OpenXR 1.0 specification that truly meets the needs of the XR industry,” he said.

Added Nandan Nayampally, vice president and general manager, client line of business at the semiconductor and software company Arm:

“It is significant when so many key players in the industry come together to create an open standard like OpenXR. We look forward to seeing adoption of the new standard, and believe that reducing barriers for cross-platform XR applications accelerates growth, innovation, and diversity in the VR and AR industry.”

Philippe Kalaf, chief executive officer at Collabora said his company was dedicated to royalty-free open standards and open source technologies. He also spoke about Monado, an open-source implementation of the OpenXR spec.

“Monado is an open-source project and codebase to harness and focus wider community effort around XR technologies,” he said. “Collabora plans to provide the technical foundation and industry leadership to accelerate the development and deployment of XR technologies on Linux while providing XR device vendors the choice to use and contribute to a Linux-based platform for their XR products.”

Microsoft also offered feedback on the new standard.

“Microsoft believes that for mixed reality to thrive, it must be open for everyone: open stores, open browsers and open developer platforms. We’re dedicated to supporting the launch of OpenXR this year on Windows Mixed Reality and HoloLens 2,” said Alex Kipman, technical fellow at Microsoft.

The Khronos Group is an open industry consortium of over 140 leading hardware and software companies creating advanced, royalty-free, acceleration standards for 3D graphics, augmented and virtual reality, vision and machine learning. Khronos standards include Vulkan, OpenGL, OpenGL ES, OpenGL SC, WebGL, SPIR-V, OpenCL, SYCL, OpenVX, NNEF, COLLADA, OpenXR and glTF.

Khronos members are enabled to contribute to the development of Khronos specifications and to vote at various stages before public deployment. They are able to accelerate the delivery of their platforms and applications through early access to specification drafts.