anchor.diff:  
   (cffi:defcfun ("aiReleaseImport" ai-release-import) :void (p-scene :pointer))
   
  +#-old-assimp
   (cffi:defcfun ("aiTransposeMatrix3" ai-transpose-matrix-3) :void (mat :pointer))
   
  +#-old-assimp
   (cffi:defcfun ("aiTransposeMatrix4" ai-transpose-matrix-4) :void (mat :pointer))
   
  +#-old-assimp
   (cffi:defcfun ("aiMultiplyMatrix3" ai-multiply-matrix-3) :void (dst :pointer)
                 (src :pointer))
   
  +#-old-assimp
   (cffi:defcfun ("aiMultiplyMatrix4" ai-multiply-matrix-4) :void (dst :pointer)
                 (src :pointer))
   
  
positive.code:   (:ai-default-log-stream-stderr 4)
    (:ai-default-log-stream-debugger 8))
  
  (cffi:defcfun ("aiGetPredefinedLogStream" ai-get-predefined-log-stream)
      ai-log-stream
    (p-streams ai-default-log-stream)
  
negative.code:   (m-num-properties :unsigned-int)
    (m-num-allocated :unsigned-int))
  
  #-old-assimp
  (cffi:defcfun ("aiGetMaterialProperty" ai-get-material-property) ai-return
    (p-mat :pointer)
    (p-key :pointer)
  