anchor.diff:            (setf (slot-value image 'texture) texture
                   (slot-value image 'size)
                   (complex (sdl:width surface) (sdl:height surface)))
  -          texture))))
  +          (values texture surface)))))
  +
  +(defmethod size ((image image))
  +  ;; Automatically load the image texture.
  +  (texture image)
  +  (slot-value image 'size))
   
   (defgeneric x (object)
     (:method ((n number)) (realpart n)))
  
positive.code:    (source
      :initarg :source)
     texture
     (size
      :reader size))
    (:documentation
     "Wrapper over an Open GL texture."))
  
  
negative.code:          (sdl-base::pixel-data pixels)))
      (values texture surface)))
  
  (defun texture (image)
    (declare (type image image))
    (if (slot-boundp image 'texture)
        (slot-value image 'texture)
        (with-slots (source) image
  