VREyeParameters.renderWidth - Web APIs 编辑

Experimental

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

The renderWidth read-only property of the VREyeParameters interface describes the recommended render target width of each eye viewport, in pixels.

This is already in device pixel units, so there's no need to multiply by Window.devicePixelRatio before setting to HTMLCanvasElement.width.

Syntax

var myRenderWidth = eyeParametersInstance.renderWidth;

Value

A number, representing the width in pixels.

Examples

navigator.getVRDisplays().then(function(displays) {
  // If a display is available, use it to present the scene
  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() {
    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);

      drawVRScene();
    });
  });
});

Specifications

Browser compatibility

BCD tables only load in the browser

See also

• WebVR API homepage.
• MozVr.com — demos, downloads, and other resources from the Mozilla VR team.