VRPose.linearVelocity

This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The linearVelocity read-only property of the VRPose interface returns an array representing the linear velocity vector of the VRDisplay at the current VRPose.timestamp, in meters per second.

In other words, the current velocity at which the sensor is moving along the x, y, and z axes.

Syntax

var myLinearVelocity = VRPose.linearVelocity;

Value

A Float32Array, or null if the VR sensor is not able to provide linear velocity data.

Examples

// rendering loop for a VR scene
function drawVRScene() {
  // WebVR: Request the next frame of the animation
  vrSceneFrame = vrDisplay.requestAnimationFrame(drawVRScene);

  // Populate frameData with the data of the next frame to display
  vrDisplay.getFrameData(frameData);

  // Retrieve the linear velocity values for use in rendering
  // curFramePose is a VRPose object
  var curFramePose = frameData.pose;
  var linVel = curFramePose.linearVelocity;
  var lvx = linVel[0];
  var lvy = linVel[1];
  var lvz = linVel[2];

  // render the scene
  ...

  // WebVR: submit the rendered frame to the VR display
  vrDisplay.submitFrame();
}

Specifications

Specification Status Comment
WebVR 1.1
The definition of 'linearVelocity' in that specification.
Editor's Draft Initial definition

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support Yes1 2 Yes

553

584

No ? ?
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidIE mobileOpera AndroidiOS Safari
Basic support No Yes5 ? ? No ? ?

1. Only works on desktop in an experimental version of Chrome (other builds won't return any devices when Navigator.getVRDisplays() is invoked).

2. This feature is behind the WebVR preference. To change preferences in Chrome, visit chrome://flags.

3. Windows support was enabled in Firefox 55.

4. macOS support was enabled in Firefox 58.

5. Currently supported only by Google Daydream.

See also

Document Tags and Contributors

 Contributors to this page: fscholz, chrisdavidmills, abbycar, Sebastianz
 Last updated by: fscholz,