anchor.diff:      (translate-sprite sp dx dy)))
   
   (defun rotate-sprite (sp dangle)
  -  (rotate-shape-2d (sprite-shape sp) dangle (sprite-x sp) (sprite-y sp))
  +  (rotate-shape-2d (sprite-shape sp) dangle (sprite-center-x sp) (sprite-center-y sp))
     (when (sprite-bbox sp) (bbox-overwrite/shape (sprite-bbox sp) (sprite-shape sp))))
   
   
  
positive.code:   color
    (flip :none))
  
  (defun sprite-set-flip (it value)
    (case value
      (:vertical (setf (shape-tex-coords (sprite-shape it)) #(0.0 1.0 1.0 1.0 1.0 0.0 0.0 0.0)))
  
negative.code:                          :color color
                           :x x :y y :width width :height height
                           :bbox bbox :flip flip
                           :shape (create-rectangle-shape x y (+ x width) (+ y height)))))
      (setf (sprite-flip sp) flip)
      (rotate-sprite sp angle)
      (when bbox (bbox-overwrite/shape (sprite-bbox sp) (sprite-shape sp)))
  