(glib:define-gboxed-opaque font-metrics "PangoFontMetrics"
  :export t
  :type-initializer "pango_font_metrics_get_type"
  :alloc (error "PangoFontMetrics cannot be created from the Lisp side."))  

The pango:font-metrics structure holds the overall metric information for a font, possibly restricted to a script. The fields of this structure are private to implementations of a font backend. See the documentation of the corresponding getters for documentation of their meaning.