anchor.diff:    (m-clip-plane-far :float)
     (m-aspect :float))
   
  -(cffi:defcenum ai-origin
  +(cffi:defcenum (ai-origin :int)
     (:ai-origin-set 0)
     (:ai-origin-cur 1)
  -  (:ai-origin-end 2)
  -  (:_ai-origin-enforce-enum-size 2147483647))
  +  (:ai-origin-end 2))
   
   (cffi:defcstruct ai-color-3d
     (r :float)
  
positive.code:   (x :float)
    (y :float))
  
  (cffi:defcenum ai-return
    (:ai-return-success 0)
    (:ai-return-failure -1)
    (:ai-return-outofmemory -3)
    (:_ai-enforce-enum-size 2147483647))
  
  (cffi:defcstruct ai-vector-key
    (m-time :double)
  
negative.code: 
  (cffi::defctype ai-file-tell-proc :pointer)
  
  (cffi:defcenum (ai-component :unsigned-int)
    (:ai-component-normals 2)
    (:ai-component-tangents-and-bitangents 4)
    (:ai-component-colors 8)
  