The VRLayerInit dictionary of the WebVR API represents a content layer (an HTMLCanvasElement or OffscreenCanvas) that you want to present in a VR display.

You can retrieve VRLayerInit objects using VRDisplay.getLayers(), and present them using the VRDisplay.requestPresent() method.

VRLayerInit.leftBounds Deprecated

Defines the left texture bounds of the canvas whose contents will be presented by the VRDisplay.

VRLayerInit.rightBounds Deprecated

Defines the right texture bounds of the canvas whose contents will be presented by the VRDisplay.

VRLayerInit.source Deprecated

Defines the canvas whose contents will be presented by the VRDisplay when VRDisplay.submitFrame() is called.

// currently returns an empty array
let layers = vrDisplay.getLayers();

if (navigator.getVRDisplays) {
  console.log("WebVR 1.1 supported");
  // Then get the displays attached to the computer
  navigator.getVRDisplays().then((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", () => {
        vrDisplay.requestPresent([{ source: canvas }]).then(() => {
          console.log("Presenting to WebVR display");

          // Here it returns an array of VRLayerInit objects
          layers = vrDisplay.getLayers();

          // …
        });
      });
    }
  });
}

VRLayerInit objects look something like this:

{
  leftBounds : [/* … */],
  rightBounds: [/* … */],
  source: canvasReference
}

This dictionary was part of the old WebVR API that has been superseded by the WebXR Device API. It is no longer on track to becoming a standard.

Until all browsers have implemented the new WebXR APIs, it is recommended to rely on frameworks, like A-Frame, Babylon.js, or Three.js, or a polyfill, to develop WebXR applications that will work across all browsers [1].

• WebVR API homepage
• https://mixedreality.mozilla.org/ — demos, downloads, and other resources from the Mozilla VR team.