pango:context-metrics (context desc language)

context -- a pango:context object
desc -- a pango:font-description instance, nil means that the font description from the context will be used
language -- a pango:language instance with the language tag of used to determine which script to get the metrics for, nil means that the language tag from the context will be used, if no language tag is set on the Pango context, metrics for the default language, as determined by the pango:language-default function, will be returned

The pango:font-metrics instance.

Get overall metric information for a particular font description. Since the metrics may be substantially different for different scripts, a language tag can be provided to indicate that the metrics should be retrieved that correspond to the script(s) used by that language.

The pango:font-description instance is interpreted in the same way as by the pango:itemize function, and the family name may be a comma separated list of figures. If characters from multiple of these families would be used to render the string, then the returned fonts would be a composite of the metrics for the fonts loaded for the individual families.