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