The VRPose interface of the WebVR API represents the state of a VR sensor at a given timestamp (which includes orientation, position, velocity, and acceleration information.)
The angularAcceleration read-only property of the VRPose interface returns the angular acceleration of the VRDisplay at the current VRPose.timestamp, in meters per second per second.
The angularVelocity read-only property of the VRPose interface returns the angular velocity of the VRDisplay at the current VRPose.timestamp, in radians per second.
The hasOrientation read-only property of the VRPositionState interface returns a boolean indicating whether the VRPositionState.orientation property is valid (i.e. if the hardware is currently registering a valid orientation). If it is false, the orientation property will return null.
The hasPosition read-only property of the VRPositionState interface returns a boolean indicating whether the VRPositionState.position property is valid (i.e. if the hardware is currently registering a valid position). If it is false, the position property will return null.
The linearAcceleration read-only property of the VRPose interface returns the linear acceleration of the VRDisplay at the current VRPose.timestamp, in meters per second per second.
The linearVelocity read-only property of the VRPose interface returns the linear velocity of the VRDisplay at the current VRPose.timestamp, in meters per second.
The orientation read-only property of the VRPositionState interface returns the orientation of the sensor at the current VRPose.timestamp, as a quarternion value.
The timestamp read-only property of the VRPose interface returns the current time stamp of the system — a monotonically increasing value representing the time since the current app was started.
The onvrdisplayconnected property of the SpeechSynthesis interface represents an event handler that will run when a compatible VR device has been connected to the computer (when the vrdisplayconnected event fires).
The onvrdisplaydisconnected event handler property of the Window interface is called when a compatible VR device has been disconnected from the computer (when the vrdisplaydisconnected event fires).
The onvrdisplaypresentchange property of the SpeechSynthesis interface represents an event handler that will run when the presenting state of a VR device changes — i.e. goes from presenting to not presenting, or vice versa (when the onvrdisplaypresentchange event fires).