diff options
Diffstat (limited to 'src/font.h')
| -rw-r--r-- | src/font.h | 30 |
1 files changed, 25 insertions, 5 deletions
diff --git a/src/font.h b/src/font.h index fb66c167efe..476944c9e42 100644 --- a/src/font.h +++ b/src/font.h @@ -508,15 +508,35 @@ struct font_driver Lisp_Object (*get_cache) P_ ((FRAME_PTR F)); /* List fonts exactly matching with FONT_SPEC on FRAME. The value - is a list of font-entities. It is assured that the properties - WEIGHT to AVGWIDTH are all nil (i.e. not specified) in FONT_SPEC. + is a list of font-entities. The font properties to be considered + are: :foundly, :family, :adstyle, :registry, :script, :lang, and + :otf. See the function `font-spec' for their meanings. Note + that the last three properties are stored in FONT_EXTRA_INDEX + slot of FONT_SPEC. + + The returned value is a list of font-entities. Each font-entity + has :type property whose value is the same as the above `type'. + It also has these properties if they are available from the + corresponding font; :foundry, :family, :adstyle, :registry, + :weight, :slant, :width, :size, :dpi, :spacing, :avgwidth. If + the font is scalable, :size and :avgwidth must be 0. + + The `open' method of the same font-backend is called with one of + the returned font-entities. If the backend needs additional + information to be used in `open' method, this method can add any + Lispy value by the property :font-entity to the entities. + This and the following `match' are the only APIs that allocate font-entities. */ Lisp_Object (*list) P_ ((Lisp_Object frame, Lisp_Object font_spec)); - /* Return a font entity most closely maching with FONT_SPEC on - FRAME. The closeness is detemined by the font backend, thus - `face-font-selection-order' is ignored here. */ + /* Return a font-entity most closely maching with FONT_SPEC on + FRAME. Which font property to consider, and how to calculate the + closeness is detemined by the font backend, thus + `face-font-selection-order' is ignored here. + + The properties that the font-entity has is the same as `list' + method. */ Lisp_Object (*match) P_ ((Lisp_Object frame, Lisp_Object font_spec)); /* Optional. |