     public func parse(container: Container, elem: XMLElement, options: [String : Any]) -> NodeType {
         var transform = MDLTransform()
         
-        // N.B. scale first, then rotate, finally translate 
+        // N.B. scale first, then rotate, finally translate
         // - but how can a shear operation be composed into this?
         
         if let scale = elem.attributes["scale"] {

                case .Mesh: break
                default: break
                }

            } else {
                // parse other nodes (custom nodes, etc)
            }

    
    public static func copy(object: NodeType) -> NodeType {
        let newTransform = MDLTransform()
        
        newTransform.scale = object.scale
        newTransform.shear = object.shear
        newTransform.rotation = object.rotation
        newTransform.translation = object.translation
        
        return newTransform
    }
}
