Khronos Releases OpenXR 1.1 to Further Streamline Cross-Platform XR Development

OpenXR 1.1 consolidates multiple extensions into the core OpenXR specification to reduce fragmentation and simplify development of advanced XR applications.

Beaverton, OR – April 15, 2024 – Today, The Khronos® Group, an open consortium of industry-leading companies creating advanced interoperability standards, announces the immediate availability of the OpenXR™ 1.1 specification. This release evolves the widely adopted OpenXR open API standard for high-performance, cross-platform access to VR, AR, and mixed reality (MR) — collectively known as XR—platforms and devices. OpenXR 1.1 consolidates widely used API extensions into the core specification to reduce fragmentation and adds new functionality to streamline the development of more powerful and efficient XR applications.

In particular, OpenXR 1.1 consolidates multiple vendor extensions for key functionality to reduce differences in application code across multiple platforms, while still remaining flexible and extensible to foster innovation in a rapidly growing and evolving market. The OpenXR Working Group will focus on managing a pipeline of extensions to develop and seek feedback on new functionality, while proactively integrating proven technology into the core specification to provide developers with robust cross-platform XR capabilities.

Today, most major XR platforms have transitioned to using OpenXR to expose current and future device capabilities. Vendors with conformant OpenXR implementations include Acer, ByteDance, Canon, HTC, Magic Leap, Meta, Microsoft, Sony, XREAL, Qualcomm, Valve, Varjo, and Collabora’s Monado open source runtime. OpenXR is also supported by all the major game and rendering engines, including Autodesk VRED, Blender, Godot, NVIDIA’s Omniverse, StereoKit, Unreal Engine, and Unity.

The OpenXR 1.1 specification can be found on the Khronos website and on GitHub OpenXR Registry.

Extensions Promoted to the OpenXR 1.1 Core Specification

OpenXR integrates the following functionality, previously available through extensions, into the core specification.

Local Floor (promoted from XR_EXT_local_floor) provides a new Reference Space with a gravity-aligned world-locked origin for standing-scale content that can be recentered to the current user position at the press of a button without a calibration procedure. It also has an estimated floor height built-in. More details about Local Floor functionality and its value to developers are available in this blog post.

Stereo with Foveated Rendering (promoted from XR_VARJO_quad_views) provides a Primary View Configuration to realize eye-tracked foveated rendering or fixed foveated rendering for XR headsets across multiple graphics rendering APIs. Its use is especially beneficial for efficiently rendering high-pixel-count displays, which put a heavy load on the GPU. The original vendor extension has been adopted natively in Unity, Unreal, and recently by NVIDIA Omniverse.

Grip Surface (promoted from XR_EXT_palm_pose) provides a Standard Pose Identifier that reliably anchors visual content relative to the user's physical hand, whether the hand position is tracked directly or inferred from a physical controller’s position and orientation.

XrUuid (promoted from XR_EXT_uuid) provides a Common Data Type to hold a Universally Unique Identifier that follows the IETF RFC 4122.

xrLocateSpaces (and its corresponding extension equivalent XR_KHR_locate_spaces) provides a Locating Spaces function to improve performance and simplify application code by enabling an application to locate an array of spaces in a single function call populating an “array of structures” (AoS), instead of being limited to locating a single space per function call.

Feature Enhancements

In addition to consolidating extensions, OpenXR 1.1 also provides developers with a set of new features and clarifications, including:

Interaction Profile Improvements

Streamline action system programming. Developers can now take advantage of these new standards:

• Interaction Profile Paths: 13 new interaction profiles have been added to the OpenXR 1.1 core specification, most promoted from vendor extensions
• Standard Identifiers: includes thumb_resting_surfaces, stylus, trigger_curl, and trigger_slide
• Standard Component: adds proximity
• Output Paths: haptic_trigger and haptic_thumb

Fundamentals

Improvements in OpenXR 1.1 provide developers with an extended set of universal tools for building enhanced XR experiences:

• XrDuration: Clarify behavior for a negative duration
• Event Polling: Clarify runtime and application behavior for polling
• Two-Call Idiom: Precise explanation for “buffer size”
• New Structures: Added color without alpha channel (XrColor3f), rectangular prism (XrExtent3Df), oriented sphere (XrSpheref), oriented box (XrBoxf), and frustum (XrFrustum)

New Error Codes

New error code XR_ERROR_INSUFFICIENT PERMISSIONS and XR_ERROR_DEPENDENCY_NOT_ENABLED help with application debugging (see xr.xml).

Specification Refinement

OpenXR 1.1 provides clearer explanations of specification intent, while removing ambiguity, and strengthening the preciseness of normative language. Affected chapters include:

• Spaces: OpenXR 1.1 adds links to Reference Spaces to easily identify them in the text. It also strengthens normative language for both runtimes and app developers
• Rendering: the XR_COMPOSITION_LAYER_CORRECT_CHROMATIC_ABERRATION_BIT is deprecated since it is not used in any shipping runtimes
• Input: mentions of “Default Bindings” are removed and timing requirements for reading input action state are clarified
• Appendix: Updated list of contributors
• Versions: A new chapter to show promoted extensions between versions

"OpenXR 1.1 marks a significant milestone in the development of this open standard that has become widely adopted throughout the XR industry. OpenXR 1.0 provided baseline capabilities and the foundation for experimentation with new functionality through extensions. Now the Working Group is pivoting to manage regular core specification updates that balance the need for flexibility to ship new functionality with consolidation of proven technology to reduce fragmentation and enable true cross-platform application portability. By simplifying development while fostering innovation, we aim to empower developers to concentrate on creating groundbreaking immersive, cross-platform experiences. OpenXR 1.1 embodies the collective dedication of the Working Group and the extended XR community to refine and advance the OpenXR standard while being responsive to the dynamic requirements of a rapidly evolving ecosystem," said Alfredo Muniz, Chair of the OpenXR Working Group.

Conformance Test Suite Enhancements

The OpenXR Conformance Test Suite (CTS), freely available on GitHub, includes updates and enhancements for the functionality that has been integrated into the OpenXR 1.1 core specification, enabling consistent implementation across all conformant platforms. A development version is published and an approved release for conformance submissions will be available in Q2.

OpenXR Roadmap and Call for Community Feedback

The OpenXR Working Group welcomes and encourages feedback from the XR developer community on their experience with using OpenXR. Such feedback is essential input to prioritizing future developments on the OpenXR roadmap so that the evolving real-world requirements of developers are met. For example, the Working Group is currently exploring multiple functionality domains such as extending hand tracking to include full body tracking, and enhanced handling of spatial entities to provide standardized methods to interact with the user’s environment in advanced spatial computing applications.

Please provide OpenXR feedback via the OpenXR Discord channel, OpenXR Forums, or the GitHub Issue Tracker.

Industry Support for OpenXR 1.1

“Collabora is thrilled about the release of OpenXR 1.1, a significant milestone that underscores the importance of free standards in the XR industry. As pioneers in the free and open source XR ecosystem, Collabora has made substantial investments in Monado, the leading open source OpenXR runtime, to ensure seamless compatibility and performance across a wide range of devices. We would like to take this opportunity to deeply appreciate the dedicated efforts of the OpenXR Working Group members who generously contributed their time, expertise, and insights to bring this release to reality. We eagerly anticipate the broader OpenXR adoption that will result from this release,” said Frederic Plourde, XR lead of Collabora.

“This marks a significant milestone for OpenXR—an impressive achievement in advancing an open ecosystem. At HTC, we remain committed to open standards, streamlining the creation of XR experiences. We will continue to support OpenXR 1.1 for both PC and AIO, are excited about the new release and look forward to the thriving growth of the OpenXR community,” said Asii Wu, vice president of HTC.

“We are delighted to know about the OpenXR 1.1 version release. Kivisense has been intensively exploring the frontier innovation in the AR world with our AR engine service. As a long time supporter of OpenXR and an ecosystem partner, we appreciated huge efforts by members in the working group who contributed their time and wisdom in it and completed it. We will keep our AR engine service as part of the OpenXR ecosystem, and help to make it more prosperous,” said Steven Zhang, founder and CEO of Kivisense.

“Meta has been committed to building an open, cross-platform standard for the XR industry since the inception of the OpenXR standard in 2016”, says Jonathan Wright, senior staff engineer at Meta. “The OpenXR 1.1 release is one more step towards making it easier for developers to build XR applications. We continue to support the evolution of the OpenXR standard as we work to build an open and interoperable XR ecosystem.”

“NVIDIA regards OpenXR as a key open standard as it enables portable access to diverse XR devices. OpenXR 1.1 is an important step in consolidating important functionality while reducing fragmentation for developers. NVIDIA is working to leverage OpenXR in its CloudXR Suite that enables flexible delivery of sophisticated immersive experiences to a broad range of devices,” said David Chu, vice president of Spatial Computing and XR, NVIDIA.

“OPPO is excited about the OpenXR 1.1 global release. It's a critical achievement for the XR industry to build a prosperous XR ecosystem. As a long-time supporter of OpenXR, we are applying OpenXR specification on OPPO's XR products. OPPO is an innovative company in exploring technologies, products, content, and services for XR. Equipped with the advanced capabilities of OpenXR to empower developers, our latest OPPO MR Glass Developer Edition represents our continuous exploration in this direction," said Yi Xu, director of XR Technology at OPPO.

"PICO is excited about the OpenXR 1.1 release, which marks another important step towards improving industry standardization for cross-platform XR applications development. PICO has been an adopter of OpenXR 1.0, providing a conformant runtime on PICO Neo3 and PICO 4 devices since 2022. PICO actively contributed to the discussions on the OpenXR 1.1 specification, and our runtime implementation will soon be updated to support OpenXR 1.1 fully. We look forward to continuing to advance cross-platform XR development together with the Working Group and the community," said Jian Zhang, head of XR Foundation engineering, PICO

“Our company is committed to building an open and inclusive XR content ecosystem to promote XR content prosperity, which is in line with the original intention of the OpenXR standard. Today, the OpenXR 1.1 version has been released, and we are honored to continue embracing this standard, providing developers with a more compatible and efficient development experience, allowing them to focus more on creative work and further enrich the XR application ecosystem and scenarios. We believe this will also bring great value to our upcoming next-generation spatial computing devices,” said Zhang Song, head of Software Technology department of Play For Dream Technologies.

"Rokid congratulates OpenXR 1.1 release and its new achievement, and we are very supportive of industry’s effort on OpenXR, and appreciate its positive contribution over a long period of time," said Zhemin Li, head of Rokid's International Business Group. "Rokid is a company focusing on human-computer interaction, hoping to make human life better through advanced technologies, and also hopes to make XR more affordable through our efforts. Rokid currently has many AR products in the market and will release a new generation of personal spatial computing suite in the near future, which will further narrow the distance between the technology and ordinary people.”

"Snapdragon Spaces is the platform of choice for many Virtual, Mixed, and Augmented Reality OpenXR conformant products today. We are thrilled with the release of the OpenXR 1.1 specification and the promotion of new extensions that accelerate the pace of innovation in XR and foster an open ecosystem and community. This is an important milestone for the XR industry, reducing fragmentation and adding new features that simplify the creation of immersive applications for developers,” said Brian Vogelsang, senior director, product management at Qualcomm Technologies, Inc.

"Unity is excited for the release of OpenXR 1.1, a step forward for standardization in the XR industry. As advocates for open ecosystems and interoperability, we recognize the importance of OpenXR in simplifying development workflows and empowering creators to build immersive experiences that can seamlessly run across a variety of hardware platforms. With OpenXR 1.1, developers using Unity can expect enhanced compatibility which will ultimately accelerate the growth of the XR community and unlock new possibilities for immersive storytelling," said Peter Kuhn, principal software engineer, Unity.

“OpenXR 1.1 brings clarity and ease of use to the widespread OpenXR standard. With the most commonly used extensions now included in the core, it will be easier for developers to have confidence in relying on the features they need. These updates also promote simplicity and uniformity as new features are added down the line; something we’re super into given our goal of an ecosystem that can apply a developer’s work across hardware and runtimes,” Nathan Nuber, programmer, Valve.

“Varjo has been a contributor and adopter of OpenXR since 2019, and we are excited to be able to equip our enterprise customers with the cutting-edge capabilities of OpenXR 1.1. Among other important updates, the quad view configuration is a core part of this release, lowering the threshold for developers to render in human-eye resolution with Varjo's mixed reality headsets. We look forward to the transformative impact OpenXR 1.1 will have on the XR industry at large,” said Denny Rönngren, OpenXR system architect at Varjo.

"XREAL enthusiastically welcomes the OpenXR 1.1 release, a key milestone in fostering unified development for immersive experiences. We are gearing up for the launch of our new product lineup in 2024, which includes an innovative computing device, a continuously updated SDK package, and the XREAL Nebula OS. Committed to integrating OpenXR 1.1 specifications across our entire product line, we aim to provide developers with the essential tools for crafting innovative AR and VR experiences across platforms. We're excited to contribute to this global endeavor, advancing the potential of virtual and augmented reality," said Yu Zhang, vice president of software development, XREAL.

About Khronos

The Khronos Group is an open, non-profit, member-driven consortium of over 180 industry-leading companies creating advanced, royalty-free, interoperability standards for 3D graphics, metaverse, augmented and virtual reality, parallel programming, vision acceleration and machine learning. Khronos activities include 3D Commerce™, ANARI™, glTF™, Kamaros™, NNEF™, OpenCL™, OpenGL®, OpenGL® ES, OpenVG™, OpenVX™, OpenXR™, SPIR-V™, SYCL™, Vulkan®, and WebGL™. Khronos members drive the development and evolution of Khronos specifications and are able to accelerate the delivery of cutting-edge platforms and applications through early access to specification drafts and conformance tests.