pango:glyph-string-extents (glyphs font ink logical)

glyphs -- a pango:glyph-string instance
font -- a pango:font instance
ink -- a pango:rectangle instance used to store the extents of the glyph string as drawn or nil to indicate that the result is not needed
logical -- a pango:rectangle instance used to store the logical extents of the glyph string or nil to indicate that the result is not needed

Compute the logical and ink extents of a glyph string. See the documentation for the pango:font-glyph-extents function for details about the interpretation of the rectangles.