Web/API/VRDisplay/requestPresent

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

The requestPresent() method of the VRDisplay interface starts the VRDisplay presenting a scene.

Syntax

vrDisplayInstance.requestPresent(layers).then(function() {
  // Do something after the presentation has begun
});

Parameters

layers: An array of VRLayerInit objects representing the scene you want to present. At the moment, this can be a minimum of 0 and a maximum of 1.

Return value

A promise that resolves once the presentation has begun. there are a number of rules surrounding the promise's fulfillment or rejection:

If VRDisplayCapabilities.canPresent is false, or if the VRLayer array contains more than VRDisplayCapabilities.maxLayers layers, the promise will be rejected.
If the VRDisplay is already presenting when requestPresent() is called, the VRDisplay will update the VRLayer array being presented.
If a call to requestPresent() is rejected while the VRDisplay is already presenting it will end its presentation.
If requestPresent() is called outside of an engagement gesture the promise will be rejected unless the VRDisplay was already presenting. This engagement gesture is also sufficient to allow requestPointerLock() calls until presentation has ended.

Examples

if(navigator.getVRDisplays) {
  console.log('WebVR 1.1 supported');
  // Then get the displays attached to the computer
  navigator.getVRDisplays().then(function(displays) {
    // If a display is available, use it to present the scene
    if(displays.length > 0) {
      vrDisplay = displays[0];
      console.log('Display found');
      // Starting the presentation when the button is clicked: It can only be called in response to a user gesture
      btn.addEventListener('click', function() {
        if(btn.textContent === 'Start VR display') {
          vrDisplay.requestPresent([{ source: canvas }]).then(function() {
            console.log('Presenting to WebVR display');

            // Set the canvas size to the size of the vrDisplay viewport

            var leftEye = vrDisplay.getEyeParameters('left');
            var rightEye = vrDisplay.getEyeParameters('right');

            canvas.width = Math.max(leftEye.renderWidth, rightEye.renderWidth) * 2;
            canvas.height = Math.max(leftEye.renderHeight, rightEye.renderHeight);

            // stop the normal presentation, and start the vr presentation
            window.cancelAnimationFrame(normalSceneFrame);
            drawVRScene();

            btn.textContent = 'Exit VR display';
          });
        } else {
          vrDisplay.exitPresent();
          console.log('Stopped presenting to WebVR display');

          btn.textContent = 'Start VR display';

          // Stop the VR presentation, and start the normal presentation
          vrDisplay.cancelAnimationFrame(vrSceneFrame);
          drawScene();
        }
      });
    }
  });
}

Note: You can see this complete code at raw-webgl-example.

Specifications

Specification	Status	Comment
WebVR 1.1The definition of 'requestPresent()' in that specification.	Draft	Initial definition

Browser compatibility

Update compatibility data on GitHub

	Desktop						Mobile
	Chrome	Edge	Firefox	Internet Explorer	Opera	Safari	Android webview	Chrome for Android	Firefox for Android	Opera for Android	Safari on iOS	Samsung Internet
`requestPresent` Experimental'Deprecated'	Chrome No support No	Edge No support 15 — 79	Firefox Full support 55 Notes' Full support 55 Notes' Notes' Windows support was enabled in Firefox 55. Full support 64 Notes' Notes' macOS support was enabled in Firefox 64.	IE No support No	Opera ?	Safari No support No	WebView Android No support No	Chrome Android No support 56 — 80 Notes' Disabled' No support 56 — 80 Notes' Disabled' Notes' Only works in an experimental version of Chrome. (Other builds won't return any devices when `Navigator.getVRDisplays()` is invoked.) Notes' Daydream View supported in Chrome 56. Notes' Google Cardboard supported in Chrome 57. Disabled' From version 56 until version 80 (exclusive): this feature is behind the `WebVR` preference. To change preferences in Chrome, visit chrome://flags.	Firefox Android Full support 55	Opera Android ?	Safari iOS ?	Samsung Internet Android Full support 6.0 Notes' Full support 6.0 Notes' Notes' Google Cardboard supported in Samsung Internet 7.0.

Legend

Full support: Full support
No support: No support
Compatibility unknown: Compatibility unknown
Experimental. Expect behavior to change in the future.': Experimental. Expect behavior to change in the future.
Deprecated. Not for use in new websites.': Deprecated. Not for use in new websites.
See implementation notes.': See implementation notes.
User must explicitly enable this feature.': User must explicitly enable this feature.