VREyeParameters.offset - Web APIs 编辑

Experimental

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

Deprecated

This feature is no longer recommended. Though some browsers might still support it, it may have already been removed from the relevant web standards, may be in the process of being dropped, or may only be kept for compatibility purposes. Avoid using it, and update existing code if possible; see the compatibility table at the bottom of this page to guide your decision. Be aware that this feature may cease to work at any time.

The offset read-only property of the VREyeParameters interface represents the offset from the center point between the user's eyes to the center of the eye, measured in meters.

This value should represent half the user’s interpupillary distance (IPD), but may also represent the distance from the center point of the headset to the center point of the lens for the given eye.

Syntax

var myOffset = eyeParametersInstance.offset;

Value

A Float32Array representing a vector describing the offset from the center point between the users eyes to the center of the eye in meters.

Note:Values for the left eye will be negative; values for the right eye will be positive.

Examples

var info = document.querySelector('p');
var list = document.querySelector('ul');
var vrDisplay;

if(navigator.getVRDisplays) {
    reportFieldOfView();
} else {
  info.textContent = 'WebVR API not supported by this browser.'
}

function reportFieldOfView() {
  navigator.getVRDisplays().then(function(displays) {
    vrDisplay = displays[0];
    var lEye = vrDisplay.getEyeParameters('left');
    var rEye = vrDisplay.getEyeParameters('right');
    // lEye and rEye are VREyeParameters objects

    var lFOV = lEye.fieldOfView;
    var rFOV = rEye.fieldOfView;
    // lFOV and rFOV are VRFieldOfView objects

    var listitem1 = document.createElement('li');
    var listitem2 = document.createElement('li');

    listitem1.innerHTML = '<strong>Left eye parameters</strong>'
                 + '<br>Offset: ' + lEye.offset
                 + '<br>Render width: ' + lEye.renderWidth
                 + '<br>Render height: ' + lEye.renderHeight
                 + '<br>Up degrees: ' + lFOV.upDegrees
                 + '<br>Right degrees: ' + lFOV.rightDegrees
                 + '<br>Down degrees: ' + lFOV.downDegrees
                 + '<br>Left degrees: ' + lFOV.leftDegrees

   listitem2.innerHTML = '<strong>Right eye parameters</strong>'
                + '<br>Offset: ' + rEye.offset
                + '<br>Render width: ' + rEye.renderWidth
                + '<br>Render height: ' + rEye.renderHeight
                + '<br>Up degrees: ' + rFOV.upDegrees
                + '<br>Right degrees: ' + rFOV.rightDegrees
                + '<br>Down degrees: ' + rFOV.downDegrees
                + '<br>Left degrees: ' + rFOV.leftDegrees

    list.appendChild(listitem1);
    list.appendChild(listitem2);
  });
}

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.