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