anchor.diff:    (with-special-choices (pane)
       (let* ((region (sheet-region pane))
              (frame (polygon-points (bounding-rectangle region))))
  -      #+NIL      (draw-polygon pane frame :ink +Blue+ :filled t)
         (draw-bordered-polygon pane frame :style :outset :border-width 1))))
   
   (define-pixie-gadget menu-button pixie-menu-button-pane)
  
positive.code:       (let ((bottom (- y1 7))
  	    (left   (- left 4 (if enabled 2 0)))
  	    (right  (+ right 4 (if enabled 2 0)))
  	    (top    (- top 2 #+NIL (if enabled 2 0))))
  	(draw-rectangle* stream left top right (+ bottom (if enabled 2 1))
  			 :filled t :ink background)
  	(draw-line* stream (1+ left) (1- top) (- right 1) (1- top) :ink +white+)
  
negative.code:   (let ((y0 (bounding-rectangle-min-y (sheet-region pane)))
  	(y1 (bounding-rectangle-max-y (sheet-region pane))))
      (draw-line* pane 0 (- y1 6) +fill+ (- y1 6) :ink *3d-light-color*)
      (draw-line* pane 0 (- y1 1) +fill+ (- y1 1) :ink *3d-dark-color*)))
  
  (defmethod draw-output-border-over
      ((shape (eql 'pixie-tab-bar-border)) stream record &key &allow-other-keys)
  