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

/* Header for fontset handler.
   Copyright (C) 1998, 2001, 2002, 2003, 2004, 2005,
                 2006, 2007, 2008  Free Software Foundation, Inc.
   Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
     2005, 2006, 2007, 2008
     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 3, 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 if `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;
extern Lisp_Object Votf_script_alist;

/* 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_ ((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.
429ab54e	2	Copyright (C) 1998, 2001, 2002, 2003, 2004, 2005,
8cabe764	3	2006, 2007, 2008 Free Software Foundation, Inc.
7976eda0	4	Copyright (C) 1995, 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004,
8cabe764	5	2005, 2006, 2007, 2008
ce03bf76 KH	6	National Institute of Advanced Industrial Science and Technology (AIST)
ce03bf76 KH	7	Registration Number H14PRO021
7f907f7c	8	Copyright (C) 2003, 2006
5c23ffd5 KH	9	National Institute of Advanced Industrial Science and Technology (AIST)
5c23ffd5 KH	10	Registration Number H13PRO009
4ed46869	11
369314dc KH	12	This file is part of GNU Emacs.
	13
	14	GNU Emacs is free software; you can redistribute it and/or modify
	15	it under the terms of the GNU General Public License as published by
1427aa65	16	the Free Software Foundation; either version 3, or (at your option)
369314dc	17	any later version.
4ed46869	18
369314dc KH	19	GNU Emacs is distributed in the hope that it will be useful,
	20	but WITHOUT ANY WARRANTY; without even the implied warranty of
	21	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	22	GNU General Public License for more details.
4ed46869	23
369314dc KH	24	You should have received a copy of the GNU General Public License
369314dc KH	25	along with GNU Emacs; see the file COPYING. If not, write to
4fc5845f LK	26	the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
4fc5845f LK	27	Boston, MA 02110-1301, USA. */
4ed46869	28
aef168f8 KH	29	#ifndef EMACS_FONTSET_H
aef168f8 KH	30	#define EMACS_FONTSET_H
4ed46869	31
4ed46869 KH	32	/* This data type is used for the font_table field of window system
	33	depending data area (e.g. struct x_display_info on X window). */
	34
	35	struct font_info
	36	{
	37	/* Pointer to window system dependent font structure. On X window,
	38	this value should be coerced to (XFontStruct ). /
	39	void *font;
	40
	41	/* Index number of the font. */
	42	int font_idx;
	43
	44	/* Name to be used to find the font. */
	45	char *name;
	46
	47	/* Full name of the font given by a window system. */
	48	char *full_name;
	49
dcafe1c7 KH	50	/* Charset to encode a character code into a glyph code of the
dcafe1c7 KH	51	font. */
4ed46869 KH	52	int charset;
4ed46869 KH	53
d76d3743 AI	54	#ifdef WINDOWSNT
	55	/* Codepage of characters that will be displayed by the font. */
	56	int codepage;
	57	#endif
	58
4ed46869 KH	59	/* Maximum bound width over all existing characters of the font. On
	60	X window, this is same as (font->max_bounds.width) */
	61	int size;
	62
1afa4408 KH	63	/* Height of the font. On X window, this is the same as
1afa4408 KH	64	(font->ascent + font->descent). */
4ed46869 KH	65	int height;
4ed46869 KH	66
c7731805 KH	67	/* Width of the space glyph of the font. */
	68	int space_width;
	69
	70	/* Average width of glyphs in the font. */
	71	int average_width;
	72
e0f24100	73	/* 1 if `vertical-centering-font-regexp' matches this font name.
1afa4408 KH	74	In this case, we render characters at vartical center positions
1afa4408 KH	75	of lines. */
21fa1afa KH	76	int vertical_centering;
21fa1afa KH	77
5c23ffd5	78	/* Encoding type of the font. The value is one of
4ed46869 KH	79	0, 1, 2, or 3:
	80	0: code points 0x20..0x7F or 0x2020..0x7F7F are used
	81	1: code points 0xA0..0xFF or 0xA0A0..0xFFFF are used
	82	2: code points 0x20A0..0x7FFF are used
	83	3: code points 0xA020..0xFF7F are used
1afa4408 KH	84	If the member `font_encoder' is not NULL, this member is ignored.
1afa4408 KH	85	*/
5c23ffd5	86	unsigned char encoding_type;
4ed46869 KH	87
	88	/* The baseline position of a font is normally `ascent' value of the
	89	font. However, there exists many fonts which don't set `ascent'
	90	an appropriate value to be used as baseline position. This is
	91	typical in such ASCII fonts which are designed to be used with
	92	Chinese, Japanese, Korean characters. When we use mixture of
	93	such fonts and normal fonts (having correct `ascent' value), a
	94	display line gets very ugly. Since we have no way to fix it
	95	automatically, it is users responsibility to supply well designed
	96	fonts or correct `ascent' value of fonts. But, the latter
	97	requires heavy work (modifying all bitmap data in BDF files).
	98	So, Emacs accepts a private font property
	99	`_MULE_BASELINE_OFFSET'. If a font has this property, we
	100	calculate the baseline position by subtracting the value from
	101	`ascent'. In other words, the value indicates how many bits
	102	higher we should draw a character of the font than normal ASCII
	103	text for a better looking.
177c0ea7	104
4ed46869 KH	105	We also have to consider the fact that the concept of `baseline'
	106	differs among languages to which each character belongs. For
	107	instance, baseline should be at the bottom most position of all
	108	glyphs for Chinese, Japanese, and Korean. But, many of existing
	109	fonts for those characters doesn't have correct `ascent' values
	110	because they are designed to be used with ASCII fonts. To
	111	display characters of different language on the same line, the
	112	best way will be to arrange them in the middle of the line. So,
	113	in such a case, again, we utilize the font property
	114	`_MULE_BASELINE_OFFSET'. If the value is larger than `ascent' we
	115	calculate baseline so that a character is arranged in the middle
	116	of a line. */
	117
	118	int baseline_offset;
	119
	120	/* Non zero means a character should be composed at a position
	121	relative to the height (or depth) of previous glyphs in the
	122	following cases:
	123	(1) The bottom of the character is higher than this value. In
	124	this case, the character is drawn above the previous glyphs.
	125	(2) The top of the character is lower than 0 (i.e. baseline
	126	height). In this case, the character is drawn beneath the
	127	previous glyphs.
	128
467e7675	129	This value is taken from a private font property
4ed46869 KH	130	`_MULE_RELATIVE_COMPOSE' which is introduced by Emacs. */
	131	int relative_compose;
	132
b65dbda3 KH	133	/* Non zero means an ascent value to be used for a character
	134	registered in char-table `use-default-ascent'. */
	135	int default_ascent;
	136
4ed46869 KH	137	/* CCL program to calculate code points of the font. */
	138	struct ccl_program *font_encoder;
	139	};
	140
1afa4408 KH	141	/* A value which may appear in the member `encoding' of struch
	142	font_info indicating that a font itself doesn't tell which encoding
	143	to be used. */
c2c8997e	144	#define FONT_ENCODING_NOT_DECIDED 255
71c27002	145
5c23ffd5 KH	146	enum FONT_SPEC_INDEX
	147	{
	148	FONT_SPEC_FAMILY_INDEX,
	149	FONT_SPEC_WEIGHT_INDEX,
	150	FONT_SPEC_SLANT_INDEX,
	151	FONT_SPEC_SWIDTH_INDEX,
	152	FONT_SPEC_ADSTYLE_INDEX,
	153	FONT_SPEC_REGISTRY_INDEX,
	154	FONT_SPEC_MAX_INDEX
	155	};
	156
d748a3db AS	157	/* Forward declaration for prototypes. */
	158	struct frame;
	159
4ed46869 KH	160	/* The following six are window system dependent functions.
	161	Initialization routine of each window system should set appropriate
	162	functions to these variables. For instance, in case of X window,
	163	x_term_init does this. */
	164
	165	/* Return a pointer to struct font_info of font FONT_IDX of frame F. */
d748a3db AS	166	extern struct font_info (get_font_info_func) P_ ((struct frame *f,
d748a3db AS	167	int font_idx));
4ed46869 KH	168
	169	/* Return a list of font names which matches PATTERN. See the document of
	170	`x-list-fonts' for more detail. */
9625ce22 KH	171	extern Lisp_Object (list_fonts_func) P_ ((struct frame f,
	172	Lisp_Object pattern,
	173	int size,
	174	int maxnames));
4ed46869 KH	175
	176	/* Load a font named NAME for frame F and return a pointer to the
	177	information of the loaded font. If loading is failed, return -1. */
d748a3db AS	178	extern struct font_info (load_font_func) P_ ((struct frame *f,
d748a3db AS	179	char *name, int));
4ed46869 KH	180
	181	/* Return a pointer to struct font_info of a font named NAME for frame F.
	182	If no such font is loaded, return NULL. */
d748a3db	183	extern struct font_info (query_font_func) P_ ((struct frame f, char name));
4ed46869 KH	184
	185	/* Additional function for setting fontset or changing fontset
	186	contents of frame F. This function may change the coordinate of
	187	the frame. */
d748a3db AS	188	extern void (set_frame_fontset_func) P_ ((struct frame f, Lisp_Object arg,
d748a3db AS	189	Lisp_Object oldval));
4ed46869	190
c2c8997e KH	191	/* To find a CCL program, fs_load_font calls this function.
	192	The argument is a pointer to the struct font_info.
	193	This function set the memer `encoder' of the structure. */
	194	extern void (find_ccl_program_func) P_ ((struct font_info ));
	195
153b4d7b KH	196	extern Lisp_Object (get_font_repertory_func) P_ ((struct frame ,
	197	struct font_info *));
	198
4ed46869	199	/* Check if any window system is used now. */
d748a3db AS	200	extern void (*check_window_system_func) P_ ((void));
d748a3db AS	201
1afa4408 KH	202	struct face;
1afa4408 KH	203
874e20d3	204	extern void free_face_fontset P_ ((FRAME_PTR, struct face *));
5c23ffd5	205	extern Lisp_Object fontset_font_pattern P_ ((FRAME_PTR, struct face *, int));
1afa4408	206	extern int face_suitable_for_char_p P_ ((struct face *, int));
695871db KH	207	extern int face_for_char P_ ((FRAME_PTR, struct face *, int,
695871db KH	208	int, Lisp_Object));
153b4d7b	209	extern int make_fontset_for_ascii_face P_ ((FRAME_PTR, int, struct face *));
d1970d05	210	extern int new_fontset_from_font_name P_ ((Lisp_Object));
060855d5	211	extern void set_default_ascii_font P_ ((Lisp_Object));
153b4d7b	212	extern struct font_info fs_load_font P_ ((struct frame , char *, int));
1afa4408	213	extern int fs_query_fontset P_ ((Lisp_Object, int));
c2c8997e	214	EXFUN (Fquery_fontset, 2);
d748a3db	215	extern Lisp_Object list_fontsets P_ ((struct frame *, Lisp_Object, int));
4ed46869	216
177c0ea7	217	extern Lisp_Object Vuse_default_ascent;
32eb3f08	218	extern Lisp_Object Vignore_relative_composition;
015e1bb0	219	extern Lisp_Object Valternate_fontname_alist;
1afa4408	220	extern Lisp_Object Vfontset_alias_alist;
21fa1afa	221	extern Lisp_Object Vvertical_centering_font_regexp;
1fe41ae8	222	extern Lisp_Object Votf_script_alist;
7bca5cf2	223
5c23ffd5 KH	224	/* Load a font named FONTNAME on frame F. All fonts for frame F is
	225	stored in a table pointed by FONT_TABLE. Return a pointer to the
	226	struct font_info of the loaded font. If loading fails, return
	227	NULL. */
1afa4408	228
6a0a025b	229	#define FS_LOAD_FONT(f, fontname) fs_load_font (f, fontname, -1)
e18f9922 GM	230
	231
	232	/* Return an immutable id for font_info FONT_INFO on frame F. The
	233	reason for this macro is hat one cannot hold pointers to font_info
	234	structures in other data structures, because the table is
	235	reallocated in x_list_fonts. */
	236
	237	#define FONT_INFO_ID(F, FONT_INFO) \
	238	(FONT_INFO) - (FRAME_X_DISPLAY_INFO ((F))->font_table)
	239
	240	/* Given a font_info id ID, return a pointer to the font_info
	241	structure on frame F. If ID is invalid, return null. */
	242
	243	#define FONT_INFO_FROM_ID(F, ID) \
	244	(((ID) >= 0 && (ID) < FRAME_X_DISPLAY_INFO ((F))->font_table_size) \
	245	? (FRAME_X_DISPLAY_INFO ((F))->font_table + (ID)) \
	246	: 0)
	247
7f907f7c KH	248	#ifdef USE_FONT_BACKEND
	249	#define FONT_INFO_FROM_FACE(F, FACE) \
	250	(enable_font_backend ? (FACE)->font_info \
	251	: FONT_INFO_FROM_ID ((F), (FACE)->font_info_id))
	252	#else /* not USE_FONT_BACKEND */
	253	#define FONT_INFO_FROM_FACE(F, FACE) \
	254	FONT_INFO_FROM_ID ((F), (FACE)->font_info_id)
	255	#endif /* not USE_FONT_BACKEND */
	256
1afa4408 KH	257	extern Lisp_Object fontset_name P_ ((int));
	258	extern Lisp_Object fontset_ascii P_ ((int));
	259	extern int fontset_height P_ ((int));
	260
7f907f7c KH	261	#ifdef USE_FONT_BACKEND
	262	struct font;
	263	extern int face_for_font P_ ((struct frame , struct font , struct face *));
ff35ddd4	264	extern int new_fontset_from_font P_ ((Lisp_Object));
7f907f7c KH	265	extern struct font *fontset_ascii_font P_ ((FRAME_PTR, int));
	266	#endif /* USE_FONT_BACKEND */
	267
aef168f8	268	#endif /* EMACS_FONTSET_H */
92c15c34 KH	269
	270	/* arch-tag: c27cef7b-3cab-488a-8398-7a4daa96bb77
	271	(do not change this comment) */