anchor.diff:  (defun screen-dimensions ()
     (values (mezzanine.supervisor:framebuffer-width *main-screen*)
             (mezzanine.supervisor:framebuffer-height *main-screen*)))
  +
  +(defun window-at-point (x y)
  +  (dolist (win *window-list*)
  +    (when (and (>= x (window-x win))
  +               (< x (+ (window-x win) (width win)))
  +               (>= y (window-y win))
  +               (< y (+ (window-y win) (height win))))
  +      (return win))))
   
   (defun clip-rectangle (x y w h clip-x clip-y clip-w clip-h)
     "Clip the rectangle X,Y,W,H so it falls entirely within the clip rectangle."
  
positive.code:     (setf *mouse-buttons* buttons)
      ;; Dispatch events and stuff...
      ;; Raise windows when clicked on, deal with drag, etc.
      #+(or)(do-something)
      (when (or (not (zerop x-motion))
                (not (zerop y-motion)))
  
negative.code:     (setf (window-x win) 0
            (window-y win) 0)
      (push win *window-list*)
      (when *active-window*
        (send-event *active-window* (make-instance 'window-activation-event
                                                   :window *active-window*
                                                   :state nil)))
      (setf *active-window* win)
      (send-event win (make-instance 'window-activation-event
                                     :window win
                                     :state t))))
  
  (defun make-window (fifo width height)
    (let ((window (make-instance 'window
  