XRSession
Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The WebXR Device API's XRSession interface represents an ongoing XR session, providing methods and properties used to interact with and control the session. To open a WebXR session, use the XRSystem interface's requestSession() method.
With XRSession methods, you can poll the viewer's position and orientation (the XRViewerPose), gather information about the user's environment, and present imagery to the user. XRSession supports both inline and immersive virtual and augmented reality modes.
Instance properties
In addition to the properties listed below, XRSession inherits properties from its parent interface, EventTarget.
depthDataFormatExperimental Read only-
Returns the depth-sensing data format with which the session was configured.
depthUsageExperimental Read only-
Returns the depth-sensing usage with which the session was configured.
domOverlayStateExperimental Read only-
Provides information about the DOM overlay, if the feature is enabled.
environmentBlendModeExperimental Read only-
Returns this session's blend mode which denotes how much of the real-world environment is visible through the XR device and how the device will blend the device imagery with it.
inputSourcesExperimental Read only-
Returns a list of this session's
XRInputSources, each representing an input device used to control the camera and/or scene. interactionModeExperimental Read only-
Returns this session's interaction mode, which describes the best space (according to the user agent) for the application to draw interactive UI for the current session.
preferredReflectionFormatExperimental Read only-
Returns this session's preferred reflection format used for lighting estimation texture data.
renderStateExperimental Read only-
An
XRRenderStateobject which contains options affecting how the imagery is rendered. This includes things such as the near and far clipping planes (distances defining how close and how far away objects can be and still get rendered), as well as field of view information. visibilityStateExperimental Read only-
A string indicating whether or not the session's imagery is visible to the user, and if so, if it's being visible but not currently the target for user events.
Instance methods
XRSession provides the following methods in addition to those inherited from its parent interface, EventTarget.
cancelAnimationFrame()Experimental-
Removes a callback from the animation frame painting callback from
XRSession's set of animation frame rendering callbacks, given the identifying handle returned by a previous call torequestAnimationFrame(). end()Experimental-
Ends the WebXR session. Returns a
promisewhich resolves when the session has been shut down. requestAnimationFrame()Experimental-
Schedules the specified method to be called the next time the user agent is working on rendering an animation frame for the WebXR device. Returns an integer value which can be used to identify the request for the purposes of canceling the callback using
cancelAnimationFrame(). This method is comparable to theWindow.requestAnimationFrame()method. requestHitTestSource()Experimental-
Requests an
XRHitTestSourceobject that handles hit test subscription. requestHitTestSourceForTransientInput()Experimental-
Requests an
XRTransientInputHitTestSourceobject that handles hit test subscription for a transient input source. requestLightProbe()Experimental-
Requests an
XRLightProbethat estimates lighting information at a given point in the user's environment. requestReferenceSpace()Experimental-
Requests that a new
XRReferenceSpaceof the specified type be created. Returns a promise which resolves with theXRReferenceSpaceorXRBoundedReferenceSpacewhich was requested, or throws aNotSupportedErrorDOMExceptionif the requested space type isn't supported by the device. updateRenderState()Experimental-
Updates the properties of the session's render state.
Events
The following events are delivered to XRSession objects.
endExperimental-
Sent to the
XRSessionobject after the WebXR session has ended and all hardware-related functions have completed. The event is represented by an object of typeXRSessionEvent. Also available through theonendevent handler property. inputsourceschangeExperimental-
An event of type
XRInputSourcesChangeEventsent to theXRSessionwhen the list of active XR input sources has changed. Also available through theoninputsourceschangeevent handler property. selectExperimental-
An event of type
XRInputSourceEventwhich is sent to the session when one of the session's input sources has successfully completed a primary action. This generally corresponds to the user pressing a trigger, touchpad, or button, speaks a command, or performs a recognizable gesture. Theselectevent is sent after theselectstartevent is sent and immediately before theselectendevent is sent. Ifselectis not sent, then the select action was aborted before being completed. Also available through theonselectevent handler property. selectendExperimental-
An event of type
XRInputSourceEventwhich gets sent to the session object when one of its input devices finishes its primary action or gets disconnected while in the process of handling a primary action. For example: for button or trigger actions, this means the button has been released; for spoken commands, it means the user has finished speaking. This is the last of the threeselect*events to be sent. Also available through theonselectendevent handler property. selectstartExperimental-
An event of type
XRInputSourceEventwhich is sent to the session object when one of its input devices is first engaged by the user in such a way as to cause the primary action to begin. This is the first of thesession*event to be sent. Also available through theonselectstartevent handler property. squeezeExperimental-
An
XRInputSourceEventsent to indicate that a primary squeeze action has successfully completed. This indicates that the device being squeezed has been released, and may represent dropping a grabbed object, for example. It is sent immediately before thesqueezeendevent is sent to indicate that the squeeze action is over. Also available through theonsqueezeevent handler property. squeezeendExperimental-
An
XRInputSourceEventsent to theXRSessionwhen the primary squeeze action ends, whether or not the action was successful. Also available using theonsqueezeendevent handler property. squeezestartExperimental-
An event of type
XRInputSourceEventwhich is sent to theXRSessionwhen the user initially squeezes a squeezable controller. This may be, for example, a trigger which is used to represent grabbing objects, or might represent actual squeezing when wearing a haptic glove. Also available through theonsqueezestartevent handler property. visibilitychangeExperimental-
An
XRSessionEventwhich is sent to the session when its visibility state as indicated by thevisibilityStatechanges. Also available through theonvisibilitychangeevent handler property.
Example
This example establishes a new XRSession in inline mode so that it can be displayed within an HTML element, avoiding the need for a dedicated AR or VR viewing device such as a headset.
const XR = navigator.xr;
if (XR) {
XR.requestSession("inline").then((xrSession) => {
xrSession.requestReferenceSpace("local").then((xrReferenceSpace) => {
xrSession.requestAnimationFrame((time, xrFrame) => {
const viewer = xrFrame.getViewerPose(xrReferenceSpace);
gl.bindFramebuffer(xrWebGLLayer.framebuffer);
for (const xrView of viewer.views) {
const xrViewport = xrWebGLLayer.getViewport(xrView);
gl.viewport(
xrViewport.x,
xrViewport.y,
xrViewport.width,
xrViewport.height,
);
}
});
});
});
} else {
/* WebXR is not available */
}
Specifications
| Specification |
|---|
| WebXR Device API # xrsession-interface |
Browser compatibility
BCD tables only load in the browser