the text corresponding to the glyphs
the length of @text, in bytes
the embedding level of the string
an array whose length is the number of characters in text (equal to g_utf8_strlen (text, length) unless text has NUL bytes) to be filled in with the resulting character widths.
Given a #PangoGlyphString resulting from pango_shape() and the corresponding text, determine the screen width corresponding to each character. When multiple characters compose a single cluster, the width of the entire cluster is divided equally among the characters.
See also pango_glyph_item_get_logical_widths().