anchor.diff:    ((name :initarg :name
            :initform nil
            :reader layout-name)
  +   (varjo-type :initarg :type
  +               :initform nil
  +               :reader layout-varjo-type)
      (base-offset :initarg :base-offset
                   :initform nil
                   :reader layout-base-offset)
  
positive.code:     (make-instance
       'std-140
       :name name
       :base-offset base-offset
       :base-alignment base-alignment
       :aligned-offset (calc-aligned-offset base-offset base-alignment)
  
negative.code:     (make-instance
       'std-140
       :name name
       :type type
       :base-offset base-offset
       :base-alignment base-alignment
       :aligned-offset (calc-aligned-offset base-offset base-alignment)
  