An encoding vector within a font layoyt, maps the characters codes to the names.

Usually the PostScript fonts have a default encoding vector mapping the standard ASCII characters, but not the extended ones, like the accented characters of the Latin 1 character set.

Therefore, to be able to use these characters, their names must be known by the application generating the PostScript, in order to be able to generate a new encoding vector. GN4 picks the names from the layout, this allows to accommodate any kind of PostScript font, even a non-standard one, provided that the correct character names are inserted in the layout.

Characters that do not have a PostScript name in the layout are supposed to be already correctly defined in the default encoding vector of the font.