function mg_convert_type, type1, type2
compile_opt strictarr
types = [[-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1], $
[-1, 1, 2, 3, 4, 5, 6, -1, -1, 9, -1, -1, 12, 13, 14, 15], $
[-1, 2, 2, 3, 4, 5, 6, -1, -1, 9, -1, -1, 3, 14, 14, 4], $
[-1, 3, 3, 3, 4, 5, 6, -1, -1, 9, -1, -1, 3, 14, 14, 4], $
[-1, 4, 4, 4, 4, 5, 6, -1, -1, 9, -1, -1, 4, 4, 4, 4], $
[-1, 5, 5, 5, 5, 5, 9, -1, -1, 9, -1, -1, 5, 5, 5, 5], $
[-1, 6, 6, 6, 6, 9, 6, -1, -1, 9, -1, -1, 6, 6, 6, 6], $
[-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1], $
[-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1], $
[-1, 9, 9, 9, 9, 9, 9, -1, -1, 9, -1, -1, 9, 9, 9, 9], $
[-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1], $
[-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1], $
[-1, 12, 3, 3, 4, 5, 6, -1, -1, 9, -1, -1, 12, 13, 14, 15], $
[-1, 13, 14, 14, 4, 5, 6, -1, -1, 9, -1, -1, 13, 13, 14, 15], $
[-1, 14, 14, 14, 4, 5, 6, -1, -1, 9, -1, -1, 14, 14, 14, 4], $
[-1, 15, 4, 4, 4, 5, 6, -1, -1, 9, -1, -1, 15, 15, 4, 15]]
return, types[type1, type2]
end