anchor.diff:  
   ;; Top-level-sheet
   
  +;; this is evil.
   (defmethod compute-extremum :after ((pane top-level-sheet-pane))
     (with-slots (space-requirement) pane
       (setf (xlib:wm-normal-hints (sheet-direct-mirror pane))
  
positive.code:   (make-translation-transformation (xlib:drawable-x mirror)
                                     (xlib:drawable-y mirror)))
  
  (defmethod port-set-sheet-region ((port clx-port) (graft graft) region)
    (declare (ignore region))
    nil)
  
  (defmethod port-set-sheet-region ((port clx-port) (sheet mirrored-sheet-mixin) region)
    (let ((mirror (sheet-direct-mirror sheet)))
      (multiple-value-bind (x1 y1 x2 y2) (bounding-rectangle* region)
        (setf (xlib:drawable-width mirror) (round (- x2 x1))
  	    (xlib:drawable-height mirror) (round (- y2 y1))))))
  
  (defmethod port-set-sheet-transformation ((port clx-port) (graft graft) transformation)
    (declare (ignore transformation))
    nil)
  
  (defmethod port-set-sheet-transformation ((port clx-port) (pane application-pane) transformation)
    (declare (ignore transformation))
    nil)
  
  (defmethod port-set-sheet-transformation ((port clx-port) (pane interactor-pane) transformation)
    (declare (ignore transformation))
    nil)
  
  (defmethod port-set-sheet-transformation ((port clx-port) (sheet mirrored-sheet-mixin) transformation)
    (let ((mirror (sheet-direct-mirror sheet)))
      (multiple-value-bind (x y) (transform-position transformation 0 0)
        (setf (xlib:drawable-x mirror) (round x)
  	    (xlib:drawable-y mirror) (round y)))))
  
  (defmethod destroy-port :before ((port clx-port))
    (xlib:close-display (clx-port-display port)))
  
negative.code: 					      :structure-notify
  					      :pointer-motion)))
    (when (null (port-lookup-mirror port sheet))
      (let* ((desired-color (if (typep sheet 'sheet-with-medium-mixin)
                                (medium-background sheet)
                              +white+))
             (color (multiple-value-bind (r g b)
                        (color-rgb desired-color)
                      (xlib:make-color :red r :green g :blue b)))
  