This class represents an abstraction of the WebXR Device API and is internally used by [page:WebGLRenderer]. [name] also provides a public interface that allows users to enable/disable XR and perform XR related tasks like for instance retrieving controllers.
This flag notifies the renderer to be ready for XR rendering. Default is *false*. Set it to *true* if you are going to use XR in your app.
Whether XR presentation is active or not. Default is *false*. This flag is read-only and automatically set by [name].
[page:Integer index] — The index of the controller.
Returns a [page:Group] representing the so called *target ray* space of the controller.
Use this space for visualizing 3D objects that support the user in pointing tasks like UI interaction.
[page:Integer index] — The index of the controller.
Returns a [page:Group] representing the so called *grip* space of the controller.
Use this space if the user is going to hold other 3D objects like a lightsaber.
Note: If you want to show something in the user's hand AND offer a pointing ray at the same time, you'll want to attached the handheld object to the group returned by [page:.getControllerGrip]() and the ray to the group returned by [page:.getController](). The idea is to have two different groups in two different coordinate spaces for the same WebXR controller.
[page:Float framebufferScaleFactor] — The framebuffer scale factor to set.
Specifies the scaling factor to use when determining the size of the framebuffer when rendering to a XR device.
The value is relative to the default XR device display resolution. Default is *1*. A value of *0.5* would specify
a framebuffer with 50% of the display's native resolution.
Note: It is not possible to change the framebuffer scale factor while presenting XR content.
[page:String referenceSpaceType] — The reference space type to set.
Can be used to configure a spatial relationship with the user's physical environment. Depending on how the user moves in 3D space, setting an
appropriate reference space can improve tracking. Default is *local-floor*.
Please check out the [link:https://developer.mozilla.org/en-US/docs/Web/API/XRReferenceSpaceType MDN] for possible values and their use cases.
Note: It is not possible to change the reference space type while presenting XR content.
[link:https://github.com/mrdoob/three.js/blob/master/src/[path].js src/[path].js]