anchor.diff:        (context-add-cylinder context frame-name (subframe "x")
                               (quaternion-translation-2 nil (vec3* l/2 0 0))
                               length w/2 '(1 0 0)
  +                            :no-shadow t
                               :color '(1 0 0) :collision nil)
   
         (context-add-cylinder  context frame-name (subframe "y")
                                (quaternion-translation-2 nil (vec3* 0 l/2 0))
                                length w/2 '(0 1 0)
  +                             :no-shadow t
                                :color '(0 1 0) :collision nil)
         (context-add-cylinder  context frame-name (subframe "z")
                                (quaternion-translation-2 nil (vec3* 0 0 l/2))
                                length w/2 '(0 0 1)
  +                             :no-shadow t
                                :color '(0 0 1) :collision nil)
   
         (context-add-cone context frame-name (subframe "x_arrow")
                           (quaternion-translation-2 nil (vec3* length 0 0))
                           arrow-length cone-radius 0d0 '(1 0 0)
  +                        :no-shadow t
                           :color '(1 0 0) :collision nil)
   
         (context-add-cone context frame-name (subframe "y_arrow")
                           (quaternion-translation-2 nil (vec3* 0 length 0))
                           arrow-length cone-radius 0d0 '(0 1 0)
  +                        :no-shadow t
                           :color '(0 1 0) :collision nil)
   
         (context-add-cone context frame-name (subframe "z_arrow")
                           (quaternion-translation-2 nil (vec3* 0 0 length))
                           arrow-length cone-radius 0d0 '(0 0 1)
  +                        :no-shadow t
                           :color '(0 0 1) :collision nil)
         )
   
  
positive.code: 
  
  (defun context-add-geometry (context parent name tf geometry &key
                                                                 (color '(0 0 0))
                                                                 (alpha 1d0)
                                                                 (collision t)
  
negative.code:                                name color alpha)))
  
  (defun context-add-box (context parent name tf dimensions &key
                                                             no-shadow
                                                              (color '(0 0 0))
                                                              (alpha 1d0)
                                                              (collision t)
                                                              (visual t))
    ;; Scene Graph
    (context-add-geometry context parent name tf (scene-box dimensions)
                          :no-shadow no-shadow
                          :color color :alpha alpha
                          :collision collision :visual visual)
    ;; Move It Scene
  