Monado - XR Runtime (XRT)

• What is Monado?
• Important links
• Highlights
• Supported Hardware
  • So what does that mean?
• Getting Started with Monado
• Other Information
• Code of Conduct
• Contributing & Repos
• Contact

What is Monado?

Monado is an open source XR runtime delivering immersive experiences such as VR and AR on mobile, PC/desktop, and other devices. Monado aims to be a complete and conformant implementation of the OpenXR API made by Khronos. The project is currently being developed for GNU/Linux, Android and Windows.

Most of the included VR hardware drivers are limited to Linux at this time.

On Android Monado comes with support for the built in IMU of most smartphones to enable 3DoF experiences, similar to Google Cardboard.

On Windows, mostly simulated HMD and controller drivers are usable. Direct Mode access for existing HMDs when not using NDA APIs remains a major blocker.

Important links

• Source code: https://gitlab.freedesktop.org/monado/monado
• Matrix space: https://matrix.to/#/#monado:matrix.org
• Discord server: https://discord.gg/8RkJgRJ
• IRC channel: #monado on OFTC

Highlights

• Officially an OpenXR conformant implementation of the OpenXR API
  • Supports Vulkan, OpenGL & ES, D3D11 (Windows only), D3D12 (Windows only), and Headless applications
  • Full support for Local, Stage, Local Floor, and Action space relations
  • Action based input
  • OpenXR Extensions:
    • XR_KHR_convert_timespec_time
    • XR_KHR_opengl_enable, XR_KHR_opengl_es_enable, XR_KHR_vulkan_enable, XR_KHR_vulkan_enable2
    • XR_KHR_composition_layer_depth, XR_KHR_composition_layer_cylinder, XR_KHR_composition_layer_equirect, XR_KHR_composition_layer_equirect2
    • XR_EXT_hand_tracking - with Index controllers on vive and libsurvive drivers and Leap Motion with Ultraleap v2
    • XR_EXTX_overlay - Multi-application support
    • XR_MND_headless - XrSession without graphical output and compositor
    • XR_KHR_swapchain_usage_input_attachment_bit / XR_MND_swapchain_usage_input_attachment_bit
    • XR_MNDX_egl_enable - Alternative to XR_KHR_opengl_enable and XR_KHR_opengl_es_enable on Desktop
    • XR_KHR_android_create_instance, XR_KHR_loader_init and XR_KHR_loader_init_android - android specific
    • And many more. See the EXTENSIONS list in this script for the full list of extensions Monado can currently support
• 6DoF tracking
  • PSVR and PS Move controllers: Outside-in tracking framework with stereo cameras such as PS4 camera
    • Work in progress on outside-in tracking with mono cameras such as consumer webcams
  • Inside-out (VIO/SLAM) tracking using an improved basalt fork with all supported stereo or more cameras such as Windows Mixed Reality, Oculus Rift S, Valve Index
• Video stream and filter framework for tracking components
• Initial Android support
  • Cardboard viewer
• XR Compositor
  • Direct mode on AMD, NVidia and Intel GPUs
  • Mesh based distortion with generators for various supported HMDs such as Vive/Index parameters, Windows Mixed Reality, OpenHMD’s Panotools
  • Supports multiple simultaneous projection layers and quad layers
• Driver framework allowing easy integration of existing drivers
  • Out of the box support for multiple XR devices with open source drivers

Supported Hardware

These are the XR devices that are natively supported with open source drivers in Monado

* Monado Basalt: Experimental 6DoF tracking support with external SLAM/VIO systems.

Monado also leverages the open source drivers developed by the OpenHMD community for further HMD support.

See the OpenHMD support matrix for a list of devices supported through OpenHMD. Most notably, OpenHMD supports the Oculus Rift CV1 and Nolo CV1.

The Direct-Tek WVR2 / VR-Tek Windows VR Glasses with the 2560x1440 resolution supported through OpenHMD requires a workaround on AMD GPUs¹.

XR devices that are supported by wrapping 3rd party open source drivers

Proprietary 3rd party drivers can also be integrated. Monado currently wraps these

See also the XR Devices table in the LVRA Wiki that also includes WIP and out of tree drivers.

So what does that mean?

For end users it means Monado can be used to run OpenXR games and applications like Blender on any of the supported hardware.

For developers it means you can start developing software for OpenXR with the ability to debug and inspect the source code of the entire XR software stack from your application to the HMD driver.

Monado transparently takes care of direct mode and distortion correction without developers having to write a single line of X11 code.

Getting Started with Monado

• Setup Monado, libsurvive and OpenComposite for the Valve Index
• Getting Started installing and running applications with Monado
• The OpenXR 1.0 specification
• List of Open Source applications and examples
• Tested Multi-GPU configurations (e.g. Optimus)
• For hacking on Monado (e.g. implementing OpenXR extensions), take a look at the online doxygen documentation
• Use Monado’s hardware drivers in SteamVR

Other Information

• Khronos’ Monado-Improvements project 2023

Code of Conduct

We follow the standard freedesktop.org code of conduct, available at https://www.freedesktop.org/wiki/CodeOfConduct/, which is based on the Contributor Covenant.

Instances of abusive, harassing, or otherwise unacceptable behavior may be reported by contacting:

• First-line project contacts: see main repo README https://gitlab.freedesktop.org/monado/monado#contributing-code-of-conduct
• freedesktop.org contacts: see most recent list at https://www.freedesktop.org/wiki/CodeOfConduct/

Contributing & Repos

The main repository is https://gitlab.freedesktop.org/monado/monado and has documentation on how to get started and contribute. Please refer to the CONTRIBUTING.md file in the repository for details.

Contributions to the information on this website itself are welcome at https://gitlab.freedesktop.org/monado/webpage

Contact

For other questions and just hanging out you can find us here:

• Discord server.
• #monado on OFTC.

Footnotes