XRView.isFirstPersonObserver

The XRView interface's read-only isFirstPersonObserver property is a boolean indicating if the XRView is a first-person observer view.

To create video recordings of AR device cameras, you can't simply use one of the rendered eyes, as there often will be a physical offset. Some devices expose a secondary view, the first-person observer view, which has an eye of none.

To receive a first-person observer view, you need to enable the "secondary-views" feature descriptor explicitly (typically as an optional feature). See XRSystem.requestSession() for details.

The isFirstPersonObserver property then allows you to check which secondary view is a first-person observer view.

Examples

Checking for first-person observer views

// Make sure to enable "secondary-view"
navigator.xr.requestSession("immersive-ar", {
  optionalFeatures: ["secondary-views"]
});

// ...

session.requestAnimationFrame(function(frame) {
  let views = frame.getViewerPose(space);
  // Make sure to iterate over all views
  for (view of views) {
    if (view.isFirstPersonObserver) {
      renderFPO();
    } else {
      render());
    }
  }
});

Specifications

Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
isFirstPersonObserver
86
86
No
No
No
No
No
86
No
No
No
13.0

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https://developer.mozilla.org/en-US/docs/Web/API/XRView/isFirstPersonObserver