anchor.diff:                                                frame object
                                                 :configuration-map configuration-map)))
       (etypecase collision
  -      (robray::scene-box
  +      (scene-box
          (container-scene-attach-box container link object (robray::scene-box-dimension collision)
                                      tf)))
       (setf (plan-context-object-graph context)
  
positive.code:                                                       (arrow-width (* 2 width))
                                                        (arrow-length (* 1 arrow-width)))
    (setf (plan-context-object-graph context)
          (robray::draw-items (plan-context-object-graph context)
                              frame-name
                              (robray::item-frame-marker (robray::draw-subframe frame-name "marker")
                                                         :length length
                                                         :width width
                                                         :arrow-width arrow-width
                                                         :arrow-length arrow-length)
                              :options (draw-options :no-shadow t :alpha alpha
                                                     :visual t :collision nil))))
  
  (defun context-remove-object (context frame-name)
    (setf (plan-context-object-graph context)
  
negative.code:                         geometry
                          tf
                          (options nil))
    "Add geometry to the context."
    ;; Add to object-graph
    (setf (plan-context-object-graph context)
          (draw-geometry (plan-context-object-graph context)
  