function findAllScenes(el) {
  var matchingElements = [];
  var allElements = el.getElementsByTagName('*');
  for (var i = 0, n = allElements.length; i < n; i++) {
    if (allElements[i].isScene) {
      // Element exists with isScene set.
      matchingElements.push(allElements[i]);
    }
  }
  return matchingElements;
}
Finds all elements under the element that have the isScene
property set to true