XRTransientInputHitTestResult: свойство inputSource

// frame loop
function onXRFrame(time, xrFrame) {
  let hitTestResults = xrFrame.getHitTestResultsForTransientInput(
    transientHitTestSource,
  );

  hitTestResults.forEach((resultsPerInputSource) => {
    if (resultsPerInputSource.inputSource === myPreferredInputSource) {
      // act on hit test results from the preferred input source
    }
  });
}