WebXR Device API

WebXR Device API

Status	CR
Last Updated	1 June 2022
Editor(s)	Brandon Jones, Manish Goregaokar, Rik Cabanier
Former Editor(s)	Nell Waliczek
CG or WG?	WG

The WebXR Device API is the primary specification associated with WebXR, as it defines how to handle fundamental features such as connecting to the AR or VR hardware, rendering to the display, and handling input from any associated motion controllers.

WebIDL

partial interface Navigator {
  [SecureContext, SameObject] readonly attribute XRSystem xr;
};

[SecureContext, Exposed=Window] interface XRSystem : EventTarget {
  // Methods
  Promise<boolean> isSessionSupported(XRSessionMode mode);
  [NewObject] Promise<XRSession> requestSession(XRSessionMode mode, optional XRSessionInit options = {});

  // Events
  attribute EventHandler ondevicechange;
};

enum XRSessionMode {
  "inline",
  "immersive-vr",
  "immersive-ar"
};

dictionary XRSessionInit {
  sequence<any> requiredFeatures;
  sequence<any> optionalFeatures;
};

enum XRVisibilityState {
  "visible",
  "visible-blurred",
  "hidden",
};

[SecureContext, Exposed=Window] interface XRSession : EventTarget {
  // Attributes
  readonly attribute XRVisibilityState visibilityState;
  readonly attribute float? frameRate;
  readonly attribute Float32Array? supportedFrameRates;
  [SameObject] readonly attribute XRRenderState renderState;
  [SameObject] readonly attribute XRInputSourceArray inputSources;

  // Methods
  undefined updateRenderState(optional XRRenderStateInit state = {});
  Promise<undefined> updateTargetFrameRate(float rate);
  [NewObject] Promise<XRReferenceSpace> requestReferenceSpace(XRReferenceSpaceType type);

  unsigned long requestAnimationFrame(XRFrameRequestCallback callback);
  undefined cancelAnimationFrame(unsigned long handle);

  Promise<undefined> end();

  // Events
  attribute EventHandler onend;
  attribute EventHandler oninputsourceschange;
  attribute EventHandler onselect;
  attribute EventHandler onselectstart;
  attribute EventHandler onselectend;
  attribute EventHandler onsqueeze;
  attribute EventHandler onsqueezestart;
  attribute EventHandler onsqueezeend;
  attribute EventHandler onvisibilitychange;
  attribute EventHandler onframeratechange;
};

dictionary XRRenderStateInit {
  double depthNear;
  double depthFar;
  double inlineVerticalFieldOfView;
  XRWebGLLayer? baseLayer;
  sequence<XRLayer>? layers;
};

[SecureContext, Exposed=Window] interface XRRenderState {
  readonly attribute double depthNear;
  readonly attribute double depthFar;
  readonly attribute double? inlineVerticalFieldOfView;
  readonly attribute XRWebGLLayer? baseLayer;
};

callback XRFrameRequestCallback = undefined (DOMHighResTimeStamp time, XRFrame frame);

[SecureContext, Exposed=Window] interface XRFrame {
  [SameObject] readonly attribute XRSession session;
  readonly attribute DOMHighResTimeStamp predictedDisplayTime;

  XRViewerPose? getViewerPose(XRReferenceSpace referenceSpace);
  XRPose? getPose(XRSpace space, XRSpace baseSpace);
};

[SecureContext, Exposed=Window] interface XRSpace : EventTarget {

};

enum XRReferenceSpaceType {
  "viewer",
  "local",
  "local-floor",
  "bounded-floor",
  "unbounded"
};

[SecureContext, Exposed=Window]
interface XRReferenceSpace : XRSpace {
  [NewObject] XRReferenceSpace getOffsetReferenceSpace(XRRigidTransform originOffset);

  attribute EventHandler onreset;
};

[SecureContext, Exposed=Window]
interface XRBoundedReferenceSpace : XRReferenceSpace {
  readonly attribute FrozenArray<DOMPointReadOnly> boundsGeometry;
};

enum XREye {
  "none",
  "left",
  "right"
};

[SecureContext, Exposed=Window] interface XRView {
  readonly attribute XREye eye;
  readonly attribute Float32Array projectionMatrix;
  [SameObject] readonly attribute XRRigidTransform transform;
  readonly attribute double? recommendedViewportScale;

  undefined requestViewportScale(double? scale);
};

[SecureContext, Exposed=Window] interface XRViewport {
  readonly attribute long x;
  readonly attribute long y;
  readonly attribute long width;
  readonly attribute long height;
};

[SecureContext, Exposed=Window]
interface XRRigidTransform {
  constructor(optional DOMPointInit position = {}, optional DOMPointInit orientation = {});
  [SameObject] readonly attribute DOMPointReadOnly position;
  [SameObject] readonly attribute DOMPointReadOnly orientation;
  readonly attribute Float32Array matrix;
  [SameObject] readonly attribute XRRigidTransform inverse;
};

[SecureContext, Exposed=Window] interface XRPose {
  [SameObject] readonly attribute XRRigidTransform transform;
  [SameObject] readonly attribute DOMPointReadOnly? linearVelocity;
  [SameObject] readonly attribute DOMPointReadOnly? angularVelocity;

  readonly attribute boolean emulatedPosition;
};

[SecureContext, Exposed=Window] interface XRViewerPose : XRPose {
  [SameObject] readonly attribute FrozenArray<XRView> views;
};

enum XRHandedness {
  "none",
  "left",
  "right"
};

enum XRTargetRayMode {
  "gaze",
  "tracked-pointer",
  "screen"
};

[SecureContext, Exposed=Window]
interface XRInputSource {
  readonly attribute XRHandedness handedness;
  readonly attribute XRTargetRayMode targetRayMode;
  [SameObject] readonly attribute XRSpace targetRaySpace;
  [SameObject] readonly attribute XRSpace? gripSpace;
  [SameObject] readonly attribute FrozenArray<DOMString> profiles;
};

[SecureContext, Exposed=Window]
interface XRInputSourceArray {
  iterable<XRInputSource>;
  readonly attribute unsigned long length;
  getter XRInputSource(unsigned long index);
};

[SecureContext, Exposed=Window]
interface XRLayer : EventTarget {};


typedef (WebGLRenderingContext or
         WebGL2RenderingContext) XRWebGLRenderingContext;

dictionary XRWebGLLayerInit {
  boolean antialias = true;
  boolean depth = true;
  boolean stencil = false;
  boolean alpha = true;
  boolean ignoreDepthValues = false;
  double framebufferScaleFactor = 1.0;
};

[SecureContext, Exposed=Window]
interface XRWebGLLayer: XRLayer {
  constructor(XRSession session,
             XRWebGLRenderingContext context,
             optional XRWebGLLayerInit layerInit = {});
  // Attributes
  readonly attribute boolean antialias;
  readonly attribute boolean ignoreDepthValues;
  attribute float? fixedFoveation;

  [SameObject] readonly attribute WebGLFramebuffer? framebuffer;
  readonly attribute unsigned long framebufferWidth;
  readonly attribute unsigned long framebufferHeight;

  // Methods
  XRViewport? getViewport(XRView view);

  // Static Methods
  static double getNativeFramebufferScaleFactor(XRSession session);
};

partial dictionary WebGLContextAttributes {
    boolean xrCompatible = false;
};

partial interface mixin WebGLRenderingContextBase {
    [NewObject] Promise<undefined> makeXRCompatible();
};

[SecureContext, Exposed=Window]
interface XRSessionEvent : Event {
  constructor(DOMString type, XRSessionEventInit eventInitDict);
  [SameObject] readonly attribute XRSession session;
};

dictionary XRSessionEventInit : EventInit {
  required XRSession session;
};

[SecureContext, Exposed=Window]
interface XRInputSourceEvent : Event {
  constructor(DOMString type, XRInputSourceEventInit eventInitDict);
  [SameObject] readonly attribute XRFrame frame;
  [SameObject] readonly attribute XRInputSource inputSource;
};

dictionary XRInputSourceEventInit : EventInit {
  required XRFrame frame;
  required XRInputSource inputSource;
};

[SecureContext, Exposed=Window]
interface XRInputSourcesChangeEvent : Event {
  constructor(DOMString type, XRInputSourcesChangeEventInit eventInitDict);
  [SameObject] readonly attribute XRSession session;
  [SameObject] readonly attribute FrozenArray<XRInputSource> added;
  [SameObject] readonly attribute FrozenArray<XRInputSource> removed;
};

dictionary XRInputSourcesChangeEventInit : EventInit {
  required XRSession session;
  required FrozenArray<XRInputSource> added;
  required FrozenArray<XRInputSource> removed;

};

[SecureContext, Exposed=Window]
interface XRReferenceSpaceEvent : Event {
  constructor(DOMString type, XRReferenceSpaceEventInit eventInitDict);
  [SameObject] readonly attribute XRReferenceSpace referenceSpace;
  [SameObject] readonly attribute XRRigidTransform? transform;
};

dictionary XRReferenceSpaceEventInit : EventInit {
  required XRReferenceSpace referenceSpace;
  XRRigidTransform? transform = null;
};

dictionary XRSessionSupportedPermissionDescriptor: PermissionDescriptor {
  XRSessionMode mode;
};

dictionary XRPermissionDescriptor: PermissionDescriptor {
  XRSessionMode mode;
  sequence<any> requiredFeatures;
  sequence<any> optionalFeatures;
};

[Exposed=Window]
interface XRPermissionStatus: PermissionStatus {
  attribute FrozenArray<any> granted;
};

External Links

• Specification
• GitHub