-extern void
-_mesa_format_to_type_and_comps(gl_format format,
- GLenum *datatype, GLuint *comps);
-
-extern FetchTexelFuncF
-_mesa_get_texel_fetch_func(GLuint format, GLuint dims);
-
-extern StoreTexelFunc
-_mesa_get_texel_store_func(GLuint format);
-
-