font-info

font-info is a built-in function in `C source code'.

(font-info NAME &optional FRAME)

Return information about a font named NAME on frame FRAME.
If FRAME is omitted or nil, use the selected frame.

The returned value is a vector:
[ OPENED-NAME FULL-NAME SIZE HEIGHT BASELINE-OFFSET RELATIVE-COMPOSE
DEFAULT-ASCENT MAX-WIDTH ASCENT DESCENT SPACE-WIDTH AVERAGE-WIDTH
CAPABILITY ]
where
OPENED-NAME is the name used for opening the font,
FULL-NAME is the full name of the font,
SIZE is the pixelsize of the font,
HEIGHT is the pixel-height of the font (i.e., ascent + descent),
BASELINE-OFFSET is the upward offset pixels from ASCII baseline,
RELATIVE-COMPOSE and DEFAULT-ASCENT are the numbers controlling
how to compose characters,
MAX-WIDTH is the maximum advance width of the font,
ASCENT, DESCENT, SPACE-WIDTH, AVERAGE-WIDTH are metrics of the font
in pixels,
FILENAME is the font file name, a string (or nil if the font backend
doesn't provide a file name).
CAPABILITY is a list whose first element is a symbol representing the
font format, one of x, opentype, truetype, type1, pcf, or bdf.
The remaining elements describe the details of the font capabilities,
as follows:

If the font is OpenType font, the form of the list is
(opentype GSUB GPOS)
where GSUB shows which "GSUB" features the font supports, and GPOS
shows which "GPOS" features the font supports. Both GSUB and GPOS are
lists of the form:
((SCRIPT (LANGSYS FEATURE ...) ...) ...)

where
SCRIPT is a symbol representing OpenType script tag.
LANGSYS is a symbol representing OpenType langsys tag, or nil
representing the default langsys.
FEATURE is a symbol representing OpenType feature tag.

If the font is not an OpenType font, there are no elements
in CAPABILITY except the font format symbol.

If the named font is not yet loaded, return nil.