anchor.diff:  
   (defmacro with-output-to-rgba-pattern ((stream-var &rest options)
   				      &body body)
  -  `(with-output-to-rgba-image
  -       (,stream-var nil ,@options)
  +  `(with-output-to-rgba-image (,stream-var nil ,@options)
        ,@body))
   
   (defmacro with-output-to-image ((stream-var image &rest options)
  
positive.code: 	(realize-mirror port top-level-sheet)
  	(setf (sheet-region top-level-sheet)
  	      (clim:make-rectangle* 0 0 width height))
  	(if recording-p
  	    (progn
  	      (with-output-recording-options (stream :record t :draw nil)
  		(funcall continuation stream)
  		(medium-finish-output (sheet-medium stream)))
  	      (with-output-recording-options (stream :draw t :record nil)
  		(stream-replay stream)))
  	    (with-output-recording-options (stream :record nil :draw t)
  	      (funcall continuation stream)
  	      (medium-finish-output (sheet-medium stream))))
  	(setf result (funcall exit-fn top-level-sheet stream))))
      (destroy-port port)
      result))
  
negative.code: 
  (defmacro with-output-to-image-pattern ((stream-var &rest options)
  				      &body body)
    `(with-output-to-image (,stream-var nil ,@options)
       ,@body))
  
  (defun invoke-with-output-to-raster-image (continuation enter-fn exit-fn server format
  