clear method
      
Object3D
clear()
       
    
inherited
    Removes all child objects.
Implementation
Object3D clear() {
  for (int i = 0; i < children.length; i++) {
    final object = children[i];
    object.parent = null;
    object.dispatchEvent(_removedEvent);
  }
  children.length = 0;
  return this;
}