[bpt/emacs.git] / src / fontset.h

/* Header for fontset handler.
   Copyright (C) 1998, 2002, 2003, 2004, 2005,
                 2006 Free Software Foundation, Inc.
   Copyright (C) 1995, 1997, 2000
     National Institute of Advanced Industrial Science and Technology (AIST)
     Registration Number H14PRO021
   Copyright (C) 2003, 2006
     National Institute of Advanced Industrial Science and Technology (AIST)
     Registration Number H13PRO009

This file is part of GNU Emacs.

GNU Emacs is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
any later version.

GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with GNU Emacs; see the file COPYING.  If not, write to
the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA.  */

#ifndef EMACS_FONTSET_H
#define EMACS_FONTSET_H

/* This data type is used for the font_table field of window system
   depending data area (e.g. struct x_display_info on X window).  */

struct font_info
{
  /* Pointer to window system dependent font structure.  On X window,
     this value should be coerced to (XFontStruct *).  */
  void *font;

  /* Index number of the font.  */
  int font_idx;

  /* Name to be used to find the font.  */
  char *name;

  /* Full name of the font given by a window system.  */
  char *full_name;

  /* Charset to encode a character code into a glyph code of the
     font.  */
  int charset;

#ifdef WINDOWSNT
  /* Codepage of characters that will be displayed by the font.  */
  int codepage;
#endif

  /* Maximum bound width over all existing characters of the font.  On
     X window, this is same as (font->max_bounds.width) */
  int size;

  /* Height of the font.  On X window, this is the same as
     (font->ascent + font->descent).  */
  int height;

  /* Width of the space glyph of the font.  */
  int space_width;

  /* Average width of glyphs in the font.  */
  int average_width;

  /* 1 iff `vertical-centering-font-regexp' matches this font name.
     In this case, we render characters at vartical center positions
     of lines.  */
  int vertical_centering;

  /* Encoding type of the font.  The value is one of
     0, 1, 2, or 3:
	0: code points 0x20..0x7F or 0x2020..0x7F7F are used
	1: code points 0xA0..0xFF or 0xA0A0..0xFFFF are used
	2: code points 0x20A0..0x7FFF are used
	3: code points 0xA020..0xFF7F are used
     If the member `font_encoder' is not NULL, this member is ignored.
  */
  unsigned char encoding_type;

  /* The baseline position of a font is normally `ascent' value of the
     font.  However, there exists many fonts which don't set `ascent'
     an appropriate value to be used as baseline position.  This is
     typical in such ASCII fonts which are designed to be used with
     Chinese, Japanese, Korean characters.  When we use mixture of
     such fonts and normal fonts (having correct `ascent' value), a
     display line gets very ugly.  Since we have no way to fix it
     automatically, it is users responsibility to supply well designed
     fonts or correct `ascent' value of fonts.  But, the latter
     requires heavy work (modifying all bitmap data in BDF files).
     So, Emacs accepts a private font property
     `_MULE_BASELINE_OFFSET'.  If a font has this property, we
     calculate the baseline position by subtracting the value from
     `ascent'.  In other words, the value indicates how many bits
     higher we should draw a character of the font than normal ASCII
     text for a better looking.

     We also have to consider the fact that the concept of `baseline'
     differs among languages to which each character belongs.  For
     instance, baseline should be at the bottom most position of all
     glyphs for Chinese, Japanese, and Korean.  But, many of existing
     fonts for those characters doesn't have correct `ascent' values
     because they are designed to be used with ASCII fonts.  To
     display characters of different language on the same line, the
     best way will be to arrange them in the middle of the line.  So,
     in such a case, again, we utilize the font property
     `_MULE_BASELINE_OFFSET'.  If the value is larger than `ascent' we
     calculate baseline so that a character is arranged in the middle
     of a line.  */

  int baseline_offset;

  /* Non zero means a character should be composed at a position
     relative to the height (or depth) of previous glyphs in the
     following cases:
	(1) The bottom of the character is higher than this value.  In
	this case, the character is drawn above the previous glyphs.
	(2) The top of the character is lower than 0 (i.e. baseline
	height).  In this case, the character is drawn beneath the
	previous glyphs.

     This value is taken from a private font property
     `_MULE_RELATIVE_COMPOSE' which is introduced by Emacs.  */
  int relative_compose;

  /* Non zero means an ascent value to be used for a character
     registered in char-table `use-default-ascent'.  */
  int default_ascent;

  /* CCL program to calculate code points of the font.  */
  struct ccl_program *font_encoder;
};

/* A value which may appear in the member `encoding' of struch
   font_info indicating that a font itself doesn't tell which encoding
   to be used.  */
#define FONT_ENCODING_NOT_DECIDED 255

enum FONT_SPEC_INDEX
  {
    FONT_SPEC_FAMILY_INDEX,
    FONT_SPEC_WEIGHT_INDEX,
    FONT_SPEC_SLANT_INDEX,
    FONT_SPEC_SWIDTH_INDEX,
    FONT_SPEC_ADSTYLE_INDEX,
    FONT_SPEC_REGISTRY_INDEX,
    FONT_SPEC_MAX_INDEX
  };

/* Forward declaration for prototypes.  */
struct frame;

/* The following six are window system dependent functions.
   Initialization routine of each window system should set appropriate
   functions to these variables.  For instance, in case of X window,
   x_term_init does this.  */

/* Return a pointer to struct font_info of font FONT_IDX of frame F.  */
extern struct font_info *(*get_font_info_func) P_ ((struct frame *f,
						    int font_idx));

/* Return a list of font names which matches PATTERN.  See the document of
   `x-list-fonts' for more detail.  */
extern Lisp_Object (*list_fonts_func) P_ ((struct frame *f,
					   Lisp_Object pattern,
					   int size,
					   int maxnames));

/* Load a font named NAME for frame F and return a pointer to the
   information of the loaded font.  If loading is failed, return -1.  */
extern struct font_info *(*load_font_func) P_ ((struct frame *f,
						char *name, int));

/* Return a pointer to struct font_info of a font named NAME for frame F.
   If no such font is loaded, return NULL.  */
extern struct font_info *(*query_font_func) P_ ((struct frame *f, char *name));

/* Additional function for setting fontset or changing fontset
   contents of frame F.  This function may change the coordinate of
   the frame.  */
extern void (*set_frame_fontset_func) P_ ((struct frame *f, Lisp_Object arg,
					   Lisp_Object oldval));

/* To find a CCL program, fs_load_font calls this function.
   The argument is a pointer to the struct font_info.
   This function set the memer `encoder' of the structure.  */
extern void (*find_ccl_program_func) P_ ((struct font_info *));

extern Lisp_Object (*get_font_repertory_func) P_ ((struct frame *,
						   struct font_info *));

/* Check if any window system is used now.  */
extern void (*check_window_system_func) P_ ((void));

struct face;

extern void free_face_fontset P_ ((FRAME_PTR, struct face *));
extern Lisp_Object fontset_font_pattern P_ ((FRAME_PTR, struct face *, int));
extern int face_suitable_for_char_p P_ ((struct face *, int));
extern int face_for_char P_ ((FRAME_PTR, struct face *, int,
			      int, Lisp_Object));
extern int make_fontset_for_ascii_face P_ ((FRAME_PTR, int, struct face *));
extern int new_fontset_from_font_name P_ ((Lisp_Object));
extern void set_default_ascii_font P_ ((Lisp_Object));
extern struct font_info *fs_load_font P_ ((struct frame *, char *, int));
extern int fs_query_fontset P_ ((Lisp_Object, int));
EXFUN (Fquery_fontset, 2);
extern Lisp_Object list_fontsets P_ ((struct frame *, Lisp_Object, int));

extern Lisp_Object Vuse_default_ascent;
extern Lisp_Object Vignore_relative_composition;
extern Lisp_Object Valternate_fontname_alist;
extern Lisp_Object Vfontset_alias_alist;
extern Lisp_Object Vvertical_centering_font_regexp;

/* Load a font named FONTNAME on frame F.  All fonts for frame F is
   stored in a table pointed by FONT_TABLE.  Return a pointer to the
   struct font_info of the loaded font.  If loading fails, return
   NULL.  */

#define FS_LOAD_FONT(f, fontname) fs_load_font (f, fontname, -1)


/* Return an immutable id for font_info FONT_INFO on frame F.  The
   reason for this macro is hat one cannot hold pointers to font_info
   structures in other data structures, because the table is
   reallocated in x_list_fonts.  */

#define FONT_INFO_ID(F, FONT_INFO) \
     (FONT_INFO) - (FRAME_X_DISPLAY_INFO ((F))->font_table)

/* Given a font_info id ID, return a pointer to the font_info
   structure on frame F.  If ID is invalid, return null.  */

#define FONT_INFO_FROM_ID(F, ID)					\
     (((ID) >= 0 && (ID) < FRAME_X_DISPLAY_INFO ((F))->font_table_size)	\
      ? (FRAME_X_DISPLAY_INFO ((F))->font_table + (ID))			\
      : 0)

#ifdef USE_FONT_BACKEND
#define FONT_INFO_FROM_FACE(F, FACE)		\
  (enable_font_backend ? (FACE)->font_info	\
   : FONT_INFO_FROM_ID ((F), (FACE)->font_info_id))
#else  /* not USE_FONT_BACKEND */
#define FONT_INFO_FROM_FACE(F, FACE)	\
  FONT_INFO_FROM_ID ((F), (FACE)->font_info_id)
#endif	/* not USE_FONT_BACKEND */

extern Lisp_Object fontset_name P_ ((int));
extern Lisp_Object fontset_ascii P_ ((int));
extern int fontset_height P_ ((int));

#ifdef USE_FONT_BACKEND
struct font;
extern int face_for_font P_ ((struct frame *, struct font *, struct face *));
extern int new_fontset_from_font P_ ((FRAME_PTR, Lisp_Object));
extern struct font *fontset_ascii_font P_ ((FRAME_PTR, int));
#endif	/* USE_FONT_BACKEND */

#endif /* EMACS_FONTSET_H */

/* arch-tag: c27cef7b-3cab-488a-8398-7a4daa96bb77
   (do not change this comment) */
Commit	Line	Data
4ed46869	1	/* Header for fontset handler.
aaef169d TTN	2	Copyright (C) 1998, 2002, 2003, 2004, 2005,
aaef169d TTN	3	2006 Free Software Foundation, Inc.
ce03bf76 KH	4	Copyright (C) 1995, 1997, 2000
	5	National Institute of Advanced Industrial Science and Technology (AIST)
	6	Registration Number H14PRO021
7f907f7c	7	Copyright (C) 2003, 2006
5c23ffd5 KH	8	National Institute of Advanced Industrial Science and Technology (AIST)
5c23ffd5 KH	9	Registration Number H13PRO009
4ed46869	10
369314dc KH	11	This file is part of GNU Emacs.
	12
	13	GNU Emacs is free software; you can redistribute it and/or modify
	14	it under the terms of the GNU General Public License as published by
	15	the Free Software Foundation; either version 2, or (at your option)
	16	any later version.
4ed46869	17
369314dc KH	18	GNU Emacs is distributed in the hope that it will be useful,
	19	but WITHOUT ANY WARRANTY; without even the implied warranty of
	20	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	21	GNU General Public License for more details.
4ed46869	22
369314dc KH	23	You should have received a copy of the GNU General Public License
369314dc KH	24	along with GNU Emacs; see the file COPYING. If not, write to
4fc5845f LK	25	the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
4fc5845f LK	26	Boston, MA 02110-1301, USA. */
4ed46869	27
aef168f8 KH	28	#ifndef EMACS_FONTSET_H
aef168f8 KH	29	#define EMACS_FONTSET_H
4ed46869	30
4ed46869 KH	31	/* This data type is used for the font_table field of window system
	32	depending data area (e.g. struct x_display_info on X window). */
	33
	34	struct font_info
	35	{
	36	/* Pointer to window system dependent font structure. On X window,
	37	this value should be coerced to (XFontStruct ). /
	38	void *font;
	39
	40	/* Index number of the font. */
	41	int font_idx;
	42
	43	/* Name to be used to find the font. */
	44	char *name;
	45
	46	/* Full name of the font given by a window system. */
	47	char *full_name;
	48
dcafe1c7 KH	49	/* Charset to encode a character code into a glyph code of the
dcafe1c7 KH	50	font. */
4ed46869 KH	51	int charset;
4ed46869 KH	52
d76d3743 AI	53	#ifdef WINDOWSNT
	54	/* Codepage of characters that will be displayed by the font. */
	55	int codepage;
	56	#endif
	57
4ed46869 KH	58	/* Maximum bound width over all existing characters of the font. On
	59	X window, this is same as (font->max_bounds.width) */
	60	int size;
	61
1afa4408 KH	62	/* Height of the font. On X window, this is the same as
1afa4408 KH	63	(font->ascent + font->descent). */
4ed46869 KH	64	int height;
4ed46869 KH	65
c7731805 KH	66	/* Width of the space glyph of the font. */
	67	int space_width;
	68
	69	/* Average width of glyphs in the font. */
	70	int average_width;
	71
1afa4408 KH	72	/* 1 iff `vertical-centering-font-regexp' matches this font name.
	73	In this case, we render characters at vartical center positions
	74	of lines. */
21fa1afa KH	75	int vertical_centering;
21fa1afa KH	76
5c23ffd5	77	/* Encoding type of the font. The value is one of
4ed46869 KH	78	0, 1, 2, or 3:
	79	0: code points 0x20..0x7F or 0x2020..0x7F7F are used
	80	1: code points 0xA0..0xFF or 0xA0A0..0xFFFF are used
	81	2: code points 0x20A0..0x7FFF are used
	82	3: code points 0xA020..0xFF7F are used
1afa4408 KH	83	If the member `font_encoder' is not NULL, this member is ignored.
1afa4408 KH	84	*/
5c23ffd5	85	unsigned char encoding_type;
4ed46869 KH	86
	87	/* The baseline position of a font is normally `ascent' value of the
	88	font. However, there exists many fonts which don't set `ascent'
	89	an appropriate value to be used as baseline position. This is
	90	typical in such ASCII fonts which are designed to be used with
	91	Chinese, Japanese, Korean characters. When we use mixture of
	92	such fonts and normal fonts (having correct `ascent' value), a
	93	display line gets very ugly. Since we have no way to fix it
	94	automatically, it is users responsibility to supply well designed
	95	fonts or correct `ascent' value of fonts. But, the latter
	96	requires heavy work (modifying all bitmap data in BDF files).
	97	So, Emacs accepts a private font property
	98	`_MULE_BASELINE_OFFSET'. If a font has this property, we
	99	calculate the baseline position by subtracting the value from
	100	`ascent'. In other words, the value indicates how many bits
	101	higher we should draw a character of the font than normal ASCII
	102	text for a better looking.
177c0ea7	103
4ed46869 KH	104	We also have to consider the fact that the concept of `baseline'
	105	differs among languages to which each character belongs. For
	106	instance, baseline should be at the bottom most position of all
	107	glyphs for Chinese, Japanese, and Korean. But, many of existing
	108	fonts for those characters doesn't have correct `ascent' values
	109	because they are designed to be used with ASCII fonts. To
	110	display characters of different language on the same line, the
	111	best way will be to arrange them in the middle of the line. So,
	112	in such a case, again, we utilize the font property
	113	`_MULE_BASELINE_OFFSET'. If the value is larger than `ascent' we
	114	calculate baseline so that a character is arranged in the middle
	115	of a line. */
	116
	117	int baseline_offset;
	118
	119	/* Non zero means a character should be composed at a position
	120	relative to the height (or depth) of previous glyphs in the
	121	following cases:
	122	(1) The bottom of the character is higher than this value. In
	123	this case, the character is drawn above the previous glyphs.
	124	(2) The top of the character is lower than 0 (i.e. baseline
	125	height). In this case, the character is drawn beneath the
	126	previous glyphs.
	127
467e7675	128	This value is taken from a private font property
4ed46869 KH	129	`_MULE_RELATIVE_COMPOSE' which is introduced by Emacs. */
	130	int relative_compose;
	131
b65dbda3 KH	132	/* Non zero means an ascent value to be used for a character
	133	registered in char-table `use-default-ascent'. */
	134	int default_ascent;
	135
4ed46869 KH	136	/* CCL program to calculate code points of the font. */
	137	struct ccl_program *font_encoder;
	138	};
	139
1afa4408 KH	140	/* A value which may appear in the member `encoding' of struch
	141	font_info indicating that a font itself doesn't tell which encoding
	142	to be used. */
c2c8997e	143	#define FONT_ENCODING_NOT_DECIDED 255
71c27002	144
5c23ffd5 KH	145	enum FONT_SPEC_INDEX
	146	{
	147	FONT_SPEC_FAMILY_INDEX,
	148	FONT_SPEC_WEIGHT_INDEX,
	149	FONT_SPEC_SLANT_INDEX,
	150	FONT_SPEC_SWIDTH_INDEX,
	151	FONT_SPEC_ADSTYLE_INDEX,
	152	FONT_SPEC_REGISTRY_INDEX,
	153	FONT_SPEC_MAX_INDEX
	154	};
	155
d748a3db AS	156	/* Forward declaration for prototypes. */
	157	struct frame;
	158
4ed46869 KH	159	/* The following six are window system dependent functions.
	160	Initialization routine of each window system should set appropriate
	161	functions to these variables. For instance, in case of X window,
	162	x_term_init does this. */
	163
	164	/* Return a pointer to struct font_info of font FONT_IDX of frame F. */
d748a3db AS	165	extern struct font_info (get_font_info_func) P_ ((struct frame *f,
d748a3db AS	166	int font_idx));
4ed46869 KH	167
	168	/* Return a list of font names which matches PATTERN. See the document of
	169	`x-list-fonts' for more detail. */
9625ce22 KH	170	extern Lisp_Object (list_fonts_func) P_ ((struct frame f,
	171	Lisp_Object pattern,
	172	int size,
	173	int maxnames));
4ed46869 KH	174
	175	/* Load a font named NAME for frame F and return a pointer to the
	176	information of the loaded font. If loading is failed, return -1. */
d748a3db AS	177	extern struct font_info (load_font_func) P_ ((struct frame *f,
d748a3db AS	178	char *name, int));
4ed46869 KH	179
	180	/* Return a pointer to struct font_info of a font named NAME for frame F.
	181	If no such font is loaded, return NULL. */
d748a3db	182	extern struct font_info (query_font_func) P_ ((struct frame f, char name));
4ed46869 KH	183
	184	/* Additional function for setting fontset or changing fontset
	185	contents of frame F. This function may change the coordinate of
	186	the frame. */
d748a3db AS	187	extern void (set_frame_fontset_func) P_ ((struct frame f, Lisp_Object arg,
d748a3db AS	188	Lisp_Object oldval));
4ed46869	189
c2c8997e KH	190	/* To find a CCL program, fs_load_font calls this function.
	191	The argument is a pointer to the struct font_info.
	192	This function set the memer `encoder' of the structure. */
	193	extern void (find_ccl_program_func) P_ ((struct font_info ));
	194
153b4d7b KH	195	extern Lisp_Object (get_font_repertory_func) P_ ((struct frame ,
	196	struct font_info *));
	197
4ed46869	198	/* Check if any window system is used now. */
d748a3db AS	199	extern void (*check_window_system_func) P_ ((void));
d748a3db AS	200
1afa4408 KH	201	struct face;
1afa4408 KH	202
874e20d3	203	extern void free_face_fontset P_ ((FRAME_PTR, struct face *));
5c23ffd5	204	extern Lisp_Object fontset_font_pattern P_ ((FRAME_PTR, struct face *, int));
1afa4408	205	extern int face_suitable_for_char_p P_ ((struct face *, int));
695871db KH	206	extern int face_for_char P_ ((FRAME_PTR, struct face *, int,
695871db KH	207	int, Lisp_Object));
153b4d7b	208	extern int make_fontset_for_ascii_face P_ ((FRAME_PTR, int, struct face *));
d1970d05	209	extern int new_fontset_from_font_name P_ ((Lisp_Object));
060855d5	210	extern void set_default_ascii_font P_ ((Lisp_Object));
153b4d7b	211	extern struct font_info fs_load_font P_ ((struct frame , char *, int));
1afa4408	212	extern int fs_query_fontset P_ ((Lisp_Object, int));
c2c8997e	213	EXFUN (Fquery_fontset, 2);
d748a3db	214	extern Lisp_Object list_fontsets P_ ((struct frame *, Lisp_Object, int));
4ed46869	215
177c0ea7	216	extern Lisp_Object Vuse_default_ascent;
32eb3f08	217	extern Lisp_Object Vignore_relative_composition;
015e1bb0	218	extern Lisp_Object Valternate_fontname_alist;
1afa4408	219	extern Lisp_Object Vfontset_alias_alist;
21fa1afa	220	extern Lisp_Object Vvertical_centering_font_regexp;
7bca5cf2	221
5c23ffd5 KH	222	/* Load a font named FONTNAME on frame F. All fonts for frame F is
	223	stored in a table pointed by FONT_TABLE. Return a pointer to the
	224	struct font_info of the loaded font. If loading fails, return
	225	NULL. */
1afa4408	226
6a0a025b	227	#define FS_LOAD_FONT(f, fontname) fs_load_font (f, fontname, -1)
e18f9922 GM	228
	229
	230	/* Return an immutable id for font_info FONT_INFO on frame F. The
	231	reason for this macro is hat one cannot hold pointers to font_info
	232	structures in other data structures, because the table is
	233	reallocated in x_list_fonts. */
	234
	235	#define FONT_INFO_ID(F, FONT_INFO) \
	236	(FONT_INFO) - (FRAME_X_DISPLAY_INFO ((F))->font_table)
	237
	238	/* Given a font_info id ID, return a pointer to the font_info
	239	structure on frame F. If ID is invalid, return null. */
	240
	241	#define FONT_INFO_FROM_ID(F, ID) \
	242	(((ID) >= 0 && (ID) < FRAME_X_DISPLAY_INFO ((F))->font_table_size) \
	243	? (FRAME_X_DISPLAY_INFO ((F))->font_table + (ID)) \
	244	: 0)
	245
7f907f7c KH	246	#ifdef USE_FONT_BACKEND
	247	#define FONT_INFO_FROM_FACE(F, FACE) \
	248	(enable_font_backend ? (FACE)->font_info \
	249	: FONT_INFO_FROM_ID ((F), (FACE)->font_info_id))
	250	#else /* not USE_FONT_BACKEND */
	251	#define FONT_INFO_FROM_FACE(F, FACE) \
	252	FONT_INFO_FROM_ID ((F), (FACE)->font_info_id)
	253	#endif /* not USE_FONT_BACKEND */
	254
1afa4408 KH	255	extern Lisp_Object fontset_name P_ ((int));
	256	extern Lisp_Object fontset_ascii P_ ((int));
	257	extern int fontset_height P_ ((int));
	258
7f907f7c KH	259	#ifdef USE_FONT_BACKEND
	260	struct font;
	261	extern int face_for_font P_ ((struct frame , struct font , struct face *));
	262	extern int new_fontset_from_font P_ ((FRAME_PTR, Lisp_Object));
	263	extern struct font *fontset_ascii_font P_ ((FRAME_PTR, int));
	264	#endif /* USE_FONT_BACKEND */
	265
aef168f8	266	#endif /* EMACS_FONTSET_H */
92c15c34 KH	267
	268	/* arch-tag: c27cef7b-3cab-488a-8398-7a4daa96bb77
	269	(do not change this comment) */