anchor.diff:  (defmethod clpython:py-subs ((scene robray::scene-graph) name)
     (robray::scene-graph-find scene name))
   
  -(defmacro def-subs-accessors (type &body things)
  -  (with-gensyms (object name)
  -    `(defmethod clpython:py-subs ((,object ,type) ,name)
  -       (cond ,@(loop for (key function) in things
  -                  collect `((string= ,name ,key)
  -                            (,function ,object)))))))
   
   (def-subs-accessors robray::scene-frame
     ("name" robray::scene-frame-name)
  
positive.code:     rotation(tf2(1, [1,2,3])) =>
          #S(AMINO:QUATERNION :DATA #(0.0d0 0.0d0 0.0d0 1.0d0))
  
  "
    (rotation transform))
  
  
negative.code: "
    (inverse x))
  
  ;;;;;;;;;;;;;;;;;
  ;;; Subscript ;;;
  ;;;;;;;;;;;;;;;;;
  