merge emacs-23
[emacs.git] / src / font.h
blob952ea2694957dc2e484fc7174113a4ec205f1772
1 /* font.h -- Interface definition for font handling.
2 Copyright (C) 2006, 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
3 Copyright (C) 2006, 2007, 2008, 2009, 2010
4 National Institute of Advanced Industrial Science and Technology (AIST)
5 Registration Number H13PRO009
7 This file is part of GNU Emacs.
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 3 of the License, or
12 (at your option) any later version.
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.
19 You should have received a copy of the GNU General Public License
20 along with GNU Emacs. If not, see <http://www.gnu.org/licenses/>. */
22 #ifndef EMACS_FONT_H
23 #define EMACS_FONT_H
25 #include "ccl.h"
27 /* We have three types of Lisp objects related to font.
29 FONT-SPEC
31 Pseudo vector (length FONT_SPEC_MAX) of font properties. Some
32 properties can be left unspecified (i.e. nil). Emacs asks
33 font-drivers to find a font by FONT-SPEC. A fontset entry
34 specifies requisite properties whereas a face specifies just
35 preferable properties.
37 FONT-ENTITY
39 Pseudo vector (length FONT_ENTITY_MAX) of fully instanciated
40 font properties that a font-driver returns upon a request of
41 FONT-SPEC.
43 Note: Only the method `list' and `match' of a font-driver can
44 create this object, and should never be modified by Lisp.
46 FONT-OBJECT
48 Pseudo vector (length FONT_OBJECT_MAX) of a opend font.
50 Lisp object encapsulating "struct font". This corresponds to
51 an opened font.
53 Note: Only the method `open' of a font-driver can create this
54 object, and should never be modified by Lisp. */
56 extern Lisp_Object Qfont_spec, Qfont_entity, Qfont_object;
59 struct font_driver;
60 struct font;
61 struct glyph_string;
63 /* An enumerator for each font property. This is used as an index to
64 the vector of FONT-SPEC and FONT-ENTITY.
66 Note: The order is important and should not be changed. */
68 enum font_property_index
70 /* FONT-TYPE is a symbol indicating a font backend; currently `x',
71 `xft', `ftx' are available on X, `uniscribe' and `gdi' on
72 Windows, and `ns' under Cocoa / GNUstep. */
73 FONT_TYPE_INDEX,
75 /* FONT-FOUNDRY is a foundry name (symbol). */
76 FONT_FOUNDRY_INDEX,
78 /* FONT-FAMILY is a family name (symbol). */
79 FONT_FAMILY_INDEX,
81 /* FONT-ADSTYLE is an additional style name (symbol). */
82 FONT_ADSTYLE_INDEX,
84 /* FONT-REGISTRY is a combination of a charset-registry and
85 charset-encoding name (symbol). */
86 FONT_REGISTRY_INDEX,
88 /* FONT-WEIGHT is a numeric value of weight (e.g. medium, bold) of
89 the font. The lowest 8-bit is an index determining the
90 symbolic name, and the higher bits is the actual numeric value
91 defined in `font-weight-table'. */
92 FONT_WEIGHT_INDEX,
94 /* FONT-SLANT is a numeric value of slant (e.g. r, i, o) of the
95 font. The lowest 8-bit is an index determining the symbolic
96 name, and the higher bits is the actual numeric value defined
97 in `font-slant-table'. */
98 FONT_SLANT_INDEX,
100 /* FONT-WIDTH is a numeric value of setwidth (e.g. normal) of the
101 font. The lowest 8-bit is an index determining the symbolic
102 name, and the higher bits is the actual numeric value defined
103 `font-width-table'. */
104 FONT_WIDTH_INDEX,
106 /* FONT-SIZE is a size of the font. If integer, it is a pixel
107 size. For a font-spec, the value can be float specifying a
108 point size. The value zero means that the font is
109 scalable. */
110 FONT_SIZE_INDEX,
112 /* FONT-DPI is a resolution (dot per inch) for which the font is
113 designed. */
114 FONT_DPI_INDEX,
116 /* FONT-SPACING is a spacing (mono, proportional, charcell) of the
117 font (integer; one of enum font_spacing). */
118 FONT_SPACING_INDEX,
120 /* FONT-AVGWIDTH is an average width (1/10 pixel unit) of the
121 font. */
122 FONT_AVGWIDTH_INDEX,
124 #if 0
125 /* The following two members are to substitute for the above 6
126 members (FONT_WEIGHT_INDEX to FONT_AVGWIDTH_INDEX excluding
127 FONT_SIZE_INDEX) if it is found that font-entities consumes too
128 much memory. */
130 /* FONT-STYLE is a 24-bit integer containing indices for
131 style-related properties WEIGHT, SLANT, and WIDTH. The lowest
132 8-bit is an indice to the weight table AREF (font_style_table,
133 0), the next 8-bit is an indice to the slant table AREF
134 (font_style_table, 1), the highest 8-bit is an indice to the
135 slant table AREF (font_style_table, 2). The indice 0 indicates
136 that the corresponding style is not specified. This way, we
137 can represent at most 255 different names for each style, which
138 is surely sufficient. */
139 FONT_STYLE_INDEX,
141 /* FONT-METRICS is a 27-bit integer containing metrics-related
142 properties DPI, AVGWIDTH, SPACING. The lowest 12-bit is for
143 DPI, the next 12-bit is for AVGWIDTH, the highest 3-bit is for
144 SPACING. In each bit field, the highest bit indicates that the
145 corresponding value is set or not. This way, we can represent
146 DPI by 11-bit (0 to 2047), AVGWIDTH by 11-bit (0 to 2047),
147 SPACING by 3-bit (0 for proportional, 1 for dual, 2 for mono, 3
148 for charcell), which is surely sufficient. */
149 FONT_METRICS_INDEX,
150 #endif
152 /* In a font-spec, the value is an alist of extra information of a
153 font such as name, OpenType features, and language coverage.
154 In addition, in a font-entity, the value may contain a pair
155 (font-entity . INFO) where INFO is extra information to identify
156 a font (font-driver dependent). */
157 FONT_EXTRA_INDEX, /* alist alist */
159 /* This value is the length of font-spec vector. */
160 FONT_SPEC_MAX,
162 /* The followings are used only for a font-entity. */
164 /* List of font-objects opened from the font-entity. */
165 FONT_OBJLIST_INDEX = FONT_SPEC_MAX,
167 /* This value is the length of font-entity vector. */
168 FONT_ENTITY_MAX,
170 /* XLFD name of the font (string). */
171 FONT_NAME_INDEX = FONT_ENTITY_MAX,
173 /* Full name of the font (string). It is the name extracted from
174 the opend font, and may be different from the above. It may be
175 nil if the opened font doesn't give a name. */
176 FONT_FULLNAME_INDEX,
178 /* File name of the font or nil if a file associated with the font
179 is not available. */
180 FONT_FILE_INDEX,
182 /* Format of the font (symbol) or nil if unknown. */
183 FONT_FORMAT_INDEX,
185 /* This value is the length of font-object vector. */
186 FONT_OBJECT_MAX
189 /* Return the numeric weight value of FONT. */
190 #define FONT_WEIGHT_NUMERIC(font) \
191 (INTEGERP (AREF ((font), FONT_WEIGHT_INDEX)) \
192 ? (XINT (AREF ((font), FONT_WEIGHT_INDEX)) >> 8) : -1)
193 /* Return the numeric slant value of FONT. */
194 #define FONT_SLANT_NUMERIC(font) \
195 (INTEGERP (AREF ((font), FONT_SLANT_INDEX)) \
196 ? (XINT (AREF ((font), FONT_SLANT_INDEX)) >> 8) : -1)
197 /* Return the numeric width value of FONT. */
198 #define FONT_WIDTH_NUMERIC(font) \
199 (INTEGERP (AREF ((font), FONT_WIDTH_INDEX)) \
200 ? (XINT (AREF ((font), FONT_WIDTH_INDEX)) >> 8) : -1)
201 /* Return the symbolic weight value of FONT. */
202 #define FONT_WEIGHT_SYMBOLIC(font) \
203 font_style_symbolic (font, FONT_WEIGHT_INDEX, 0)
204 /* Return the symbolic slant value of FONT. */
205 #define FONT_SLANT_SYMBOLIC(font) \
206 font_style_symbolic (font, FONT_SLANT_INDEX, 0)
207 /* Return the symbolic width value of FONT. */
208 #define FONT_WIDTH_SYMBOLIC(font) \
209 font_style_symbolic (font, FONT_WIDTH_INDEX, 0)
210 /* Return the face-weight corresponding to the weight of FONT. */
211 #define FONT_WEIGHT_FOR_FACE(font) \
212 font_style_symbolic (font, FONT_WEIGHT_INDEX, 1)
213 /* Return the face-slant corresponding to the slant of FONT. */
214 #define FONT_SLANT_FOR_FACE(font) \
215 font_style_symbolic (font, FONT_SLANT_INDEX, 1)
216 /* Return the face-swidth corresponding to the slant of FONT. */
217 #define FONT_WIDTH_FOR_FACE(font) \
218 font_style_symbolic (font, FONT_WIDTH_INDEX, 1)
220 /* Return the numeric weight value corresponding ot the symbol NAME. */
221 #define FONT_WEIGHT_NAME_NUMERIC(name) \
222 (font_style_to_value (FONT_WEIGHT_INDEX, (name), 0) >> 8)
223 /* Return the numeric slant value corresponding ot the symbol NAME. */
224 #define FONT_SLANT_NAME_NUMERIC(name) \
225 (font_style_to_value (FONT_SLANT_INDEX, (name), 0) >> 8)
226 /* Return the numeric width value corresponding ot the symbol NAME. */
227 #define FONT_WIDTH_NAME_NUMERIC(name) \
228 (font_style_to_value (FONT_WIDTH_INDEX, (name), 0) >> 8)
230 /* Set the font property PROP of FONT to VAL. PROP is one of
231 style-related font property index (FONT_WEIGHT/SLANT/WIDTH_INDEX).
232 VAL (integer or symbol) is the numeric or symbolic style value. */
233 #define FONT_SET_STYLE(font, prop, val) \
234 ASET ((font), prop, make_number (font_style_to_value (prop, val, 1)))
236 extern Lisp_Object QCspacing, QCdpi, QCscalable, QCotf, QClang, QCscript;
237 extern Lisp_Object QCavgwidth, QCfont_entity, QCfc_unknown_spec;
239 /* Important character set symbols. */
240 extern Lisp_Object Qascii_0;
241 extern Lisp_Object Qiso8859_1, Qiso10646_1, Qunicode_bmp, Qunicode_sip;
243 /* Special ADSTYLE properties to avoid fonts used for Latin characters. */
244 extern Lisp_Object Qja, Qko;
246 /* Structure for a font-spec. */
248 struct font_spec
250 EMACS_UINT size;
251 struct Lisp_Vector *next;
252 Lisp_Object props[FONT_SPEC_MAX];
255 /* Structure for a font-entity. */
257 struct font_entity
259 EMACS_UINT size;
260 struct Lisp_Vector *next;
261 Lisp_Object props[FONT_ENTITY_MAX];
264 /* A value which may appear in the member `encoding' of struct font
265 indicating that a font itself doesn't tell which encoding to be
266 used. */
267 #define FONT_ENCODING_NOT_DECIDED 255
269 /* Structure for a font-object. */
271 struct font
273 EMACS_UINT size;
274 struct Lisp_Vector *next;
276 /* All Lisp_Object components must come first.
277 That ensures they are all aligned normally. */
279 Lisp_Object props[FONT_OBJECT_MAX];
281 /* Beyond here, there should be no more Lisp_Object components. */
283 /* Maximum bound width over all existing characters of the font. On
284 X window, this is same as (font->max_bounds.width). */
285 int max_width;
287 /* By which pixel size the font is opened. */
288 int pixel_size;
290 /* Height of the font. On X window, this is the same as
291 (font->ascent + font->descent). */
292 int height;
294 /* Width of the space glyph of the font. If the font doesn't have a
295 SPACE glyph, the value is 0. */
296 int space_width;
298 /* Average width of glyphs in the font. If the font itself doesn't
299 have that information but has glyphs of ASCII character, the
300 value is the average with of those glyphs. Otherwise, the value
301 is 0. */
302 int average_width;
304 /* Minimum glyph width (in pixels). */
305 int min_width;
307 /* Ascent and descent of the font (in pixels). */
308 int ascent, descent;
310 /* Vertical pixel width of the underline. If is zero if that
311 information is not in the font. */
312 int underline_thickness;
314 /* Vertical pixel position (relative to the baseline) of the
315 underline. If it is positive, it is below the baseline. It is
316 negative if that information is not in the font. */
317 int underline_position;
319 /* 1 if `vertical-centering-font-regexp' matches this font name.
320 In this case, we render characters at vartical center positions
321 of lines. */
322 int vertical_centering;
324 /* Encoding type of the font. The value is one of
325 0, 1, 2, or 3:
326 0: code points 0x20..0x7F or 0x2020..0x7F7F are used
327 1: code points 0xA0..0xFF or 0xA0A0..0xFFFF are used
328 2: code points 0x20A0..0x7FFF are used
329 3: code points 0xA020..0xFF7F are used
330 If the member `font_encoder' is not NULL, this member is ignored. */
331 unsigned char encoding_type;
333 /* The baseline position of a font is normally `ascent' value of the
334 font. However, there exists many fonts which don't set `ascent'
335 an appropriate value to be used as baseline position. This is
336 typical in such ASCII fonts which are designed to be used with
337 Chinese, Japanese, Korean characters. When we use mixture of
338 such fonts and normal fonts (having correct `ascent' value), a
339 display line gets very ugly. Since we have no way to fix it
340 automatically, it is users responsibility to supply well designed
341 fonts or correct `ascent' value of fonts. But, the latter
342 requires heavy work (modifying all bitmap data in BDF files).
343 So, Emacs accepts a private font property
344 `_MULE_BASELINE_OFFSET'. If a font has this property, we
345 calculate the baseline position by subtracting the value from
346 `ascent'. In other words, the value indicates how many bits
347 higher we should draw a character of the font than normal ASCII
348 text for a better looking.
350 We also have to consider the fact that the concept of `baseline'
351 differs among scripts to which each character belongs. For
352 instance, baseline should be at the bottom most position of all
353 glyphs for Chinese, Japanese, and Korean. But, many of existing
354 fonts for those characters doesn't have correct `ascent' values
355 because they are designed to be used with ASCII fonts. To
356 display characters of different language on the same line, the
357 best way will be to arrange them in the middle of the line. So,
358 in such a case, again, we utilize the font property
359 `_MULE_BASELINE_OFFSET'. If the value is larger than `ascent' we
360 calculate baseline so that a character is arranged in the middle
361 of a line. */
362 int baseline_offset;
364 /* Non zero means a character should be composed at a position
365 relative to the height (or depth) of previous glyphs in the
366 following cases:
367 (1) The bottom of the character is higher than this value. In
368 this case, the character is drawn above the previous glyphs.
369 (2) The top of the character is lower than 0 (i.e. baseline
370 height). In this case, the character is drawn beneath the
371 previous glyphs.
373 This value is taken from a private font property
374 `_MULE_RELATIVE_COMPOSE' which is introduced by Emacs. */
375 int relative_compose;
377 /* Non zero means an ascent value to be used for a character
378 registered in char-table `use-default-ascent'. */
379 int default_ascent;
381 /* CCL program to calculate code points of the font. */
382 struct ccl_program *font_encoder;
384 /* Font-driver for the font. */
385 struct font_driver *driver;
387 /* Charset to encode a character code into a glyph code of the font.
388 -1 means that the font doesn't require this information to encode
389 a character. */
390 int encoding_charset;
392 /* Charset to check if a character code is supported by the font.
393 -1 means that the contents of the font must be looked up to
394 determine it. */
395 int repertory_charset;
397 /* There will be more to this structure, but they are private to a
398 font-driver. */
401 enum font_spacing
403 FONT_SPACING_PROPORTIONAL = 0,
404 FONT_SPACING_DUAL = 90,
405 FONT_SPACING_MONO = 100,
406 FONT_SPACING_CHARCELL = 110
409 struct font_metrics
411 short lbearing, rbearing, width, ascent, descent;
414 struct font_bitmap
416 int bits_per_pixel;
417 int rows;
418 int width;
419 int pitch;
420 unsigned char *buffer;
421 int left;
422 int top;
423 int advance;
424 void *extra;
427 /* Predicates to check various font-related objects. */
429 /* 1 iff X is one of font-spec, font-entity, and font-object. */
430 #define FONTP(x) PSEUDOVECTORP (x, PVEC_FONT)
431 /* 1 iff X is font-spec. */
432 #define FONT_SPEC_P(x) \
433 (FONTP (x) && (ASIZE (x) & PSEUDOVECTOR_SIZE_MASK) == FONT_SPEC_MAX)
434 /* 1 iff X is font-entity. */
435 #define FONT_ENTITY_P(x) \
436 (FONTP (x) && (ASIZE (x) & PSEUDOVECTOR_SIZE_MASK) == FONT_ENTITY_MAX)
437 /* 1 iff X is font-object. */
438 #define FONT_OBJECT_P(x) \
439 (FONTP (x) && (ASIZE (x) & PSEUDOVECTOR_SIZE_MASK) == FONT_OBJECT_MAX)
441 /* 1 iff ENTITY can't be loaded. */
442 #define FONT_ENTITY_NOT_LOADABLE(entity) \
443 EQ (AREF (entity, FONT_OBJLIST_INDEX), Qt)
445 /* Flag ENTITY not loadable. */
446 #define FONT_ENTITY_SET_NOT_LOADABLE(entity) \
447 ASET (entity, FONT_OBJLIST_INDEX, Qt)
450 /* Check macros for various font-related objects. */
452 #define CHECK_FONT(x) \
453 do { if (! FONTP (x)) wrong_type_argument (Qfont, x); } while (0)
454 #define CHECK_FONT_SPEC(x) \
455 do { if (! FONT_SPEC_P (x)) wrong_type_argument (Qfont_spec, x); } while (0)
456 #define CHECK_FONT_ENTITY(x) \
457 do { if (! FONT_ENTITY_P (x)) wrong_type_argument (Qfont_entity, x); } while (0)
458 #define CHECK_FONT_OBJECT(x) \
459 do { if (! FONT_OBJECT_P (x)) wrong_type_argument (Qfont_object, x); } while (0)
461 #define CHECK_FONT_GET_OBJECT(x, font) \
462 do { \
463 CHECK_FONT_OBJECT (x); \
464 font = XFONT_OBJECT (x); \
465 } while (0)
467 #define XFONT_SPEC(p) \
468 (eassert (FONT_SPEC_P(p)), (struct font_spec *) XPNTR (p))
469 #define XFONT_ENTITY(p) \
470 (eassert (FONT_ENTITY_P(p)), (struct font_entity *) XPNTR (p))
471 #define XFONT_OBJECT(p) \
472 (eassert (FONT_OBJECT_P(p)), (struct font *) XPNTR (p))
473 #define XSETFONT(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_FONT))
475 /* Number of pt per inch (from the TeXbook). */
476 #define PT_PER_INCH 72.27
478 /* Return a pixel size (integer) corresponding to POINT size (double)
479 on resolution DPI. */
480 #define POINT_TO_PIXEL(POINT, DPI) ((POINT) * (DPI) / PT_PER_INCH + 0.5)
482 /* Return a point size corresponding to POINT size (integer)
483 on resolution DPI. Note that though point size is a double, we expect
484 it to be rounded to an int, so we add 0.5 here. If the desired value
485 is tenths of points (as in xfld specs), then the pixel size should
486 be multiplied BEFORE the conversion to avoid magnifying the error. */
487 #define PIXEL_TO_POINT(PIXEL, DPI) ((PIXEL) * PT_PER_INCH / (DPI) + 0.5)
489 /* Ignore the difference of font pixel sizes less than or equal to
490 this value. */
491 #define FONT_PIXEL_SIZE_QUANTUM 1
493 struct face;
495 #define FONT_INVALID_CODE 0xFFFFFFFF
497 /* Font driver. Members specified as "optional" can be NULL. */
499 struct font_driver
501 /* Symbol indicating the type of the font-driver. */
502 Lisp_Object type;
504 /* 1 iff the font's foundry, family, and adstyle names are case
505 sensitve. */
506 int case_sensitive;
508 /* Return a cache of font-entities on frame F. The cache must be a
509 cons whose cdr part is the actual cache area. */
510 Lisp_Object (*get_cache) P_ ((FRAME_PTR F));
512 /* List fonts exactly matching with FONT_SPEC on FRAME. The value
513 is a list of font-entities. The font properties to be considered
514 are: :foundry, :family, :adstyle, :registry, :script, :lang, and
515 :otf. See the function `font-spec' for their meanings. Note
516 that the last three properties are stored in FONT_EXTRA_INDEX
517 slot of FONT_SPEC.
519 The returned value is a list of font-entities. Each font-entity
520 has :type property whose value is the same as the above `type'.
521 It also has these properties if they are available from the
522 corresponding font; :foundry, :family, :adstyle, :registry,
523 :weight, :slant, :width, :size, :dpi, :spacing, :avgwidth. If
524 the font is scalable, :size and :avgwidth must be 0.
526 The `open' method of the same font-backend is called with one of
527 the returned font-entities. If the backend needs additional
528 information to be used in `open' method, this method can add any
529 Lispy value by the property :font-entity to the entities.
531 This and the following `match' are the only APIs that allocate
532 font-entities. */
533 Lisp_Object (*list) P_ ((Lisp_Object frame, Lisp_Object font_spec));
535 /* Return a font-entity most closely matching with FONT_SPEC on
536 FRAME. Which font property to consider, and how to calculate the
537 closeness is determined by the font backend, thus
538 `face-font-selection-order' is ignored here.
540 The properties that the font-entity has is the same as `list'
541 method. */
542 Lisp_Object (*match) P_ ((Lisp_Object frame, Lisp_Object font_spec));
544 /* Optional.
545 List available families. The value is a list of family names
546 (symbols). */
547 Lisp_Object (*list_family) P_ ((Lisp_Object frame));
549 /* Optional (if FONT_EXTRA_INDEX is not Lisp_Save_Value).
550 Free FONT_EXTRA_INDEX field of FONT_ENTITY. */
551 void (*free_entity) P_ ((Lisp_Object font_entity));
553 /* Open a font specified by FONT_ENTITY on frame F. If the font is
554 scalable, open it with PIXEL_SIZE. */
555 Lisp_Object (*open) P_ ((FRAME_PTR f, Lisp_Object font_entity,
556 int pixel_size));
558 /* Close FONT on frame F. */
559 void (*close) P_ ((FRAME_PTR f, struct font *font));
561 /* Optional (if FACE->extra is not used).
562 Prepare FACE for displaying characters by FONT on frame F by
563 storing some data in FACE->extra. If successful, return 0.
564 Otherwise, return -1. */
565 int (*prepare_face) P_ ((FRAME_PTR f, struct face *face));
567 /* Optional.
568 Done FACE for displaying characters by FACE->font on frame F. */
569 void (*done_face) P_ ((FRAME_PTR f, struct face *face));
571 /* Optional.
572 If FONT (FONT-ENTITY or FONT-OBJECT) has a glyph for character C
573 (Unicode code point), return 1. If not, return 0. If FONT is
574 FONT-ENTITY and it must be opened to check it, return -1. */
575 int (*has_char) P_ ((Lisp_Object font, int c));
577 /* Return a glyph code of FONT for characer C (Unicode code point).
578 If FONT doesn't have such a glyph, return FONT_INVALID_CODE. */
579 unsigned (*encode_char) P_ ((struct font *font, int c));
581 /* Computate the total metrics of the NGLYPHS glyphs specified by
582 the font FONT and the sequence of glyph codes CODE, and store the
583 result in METRICS. */
584 int (*text_extents) P_ ((struct font *font,
585 unsigned *code, int nglyphs,
586 struct font_metrics *metrics));
588 /* Optional.
589 Draw glyphs between FROM and TO of S->char2b at (X Y) pixel
590 position of frame F with S->FACE and S->GC. If WITH_BACKGROUND
591 is nonzero, fill the background in advance. It is assured that
592 WITH_BACKGROUND is zero when (FROM > 0 || TO < S->nchars). */
593 int (*draw) P_ ((struct glyph_string *s, int from, int to,
594 int x, int y, int with_background));
596 /* Optional.
597 Store bitmap data for glyph-code CODE of FONT in BITMAP. It is
598 intended that this method is callled from the other font-driver
599 for actual drawing. */
600 int (*get_bitmap) P_ ((struct font *font, unsigned code,
601 struct font_bitmap *bitmap,
602 int bits_per_pixel));
604 /* Optional.
605 Free bitmap data in BITMAP. */
606 void (*free_bitmap) P_ ((struct font *font, struct font_bitmap *bitmap));
608 /* Optional.
609 Return an outline data for glyph-code CODE of FONT. The format
610 of the outline data depends on the font-driver. */
611 void *(*get_outline) P_ ((struct font *font, unsigned code));
613 /* Optional.
614 Free OUTLINE (that is obtained by the above method). */
615 void (*free_outline) P_ ((struct font *font, void *outline));
617 /* Optional.
618 Get coordinates of the INDEXth anchor point of the glyph whose
619 code is CODE. Store the coordinates in *X and *Y. Return 0 if
620 the operations was successfull. Otherwise return -1. */
621 int (*anchor_point) P_ ((struct font *font, unsigned code, int index,
622 int *x, int *y));
624 /* Optional.
625 Return a list describing which scripts/languages FONT
626 supports by which GSUB/GPOS features of OpenType tables. */
627 Lisp_Object (*otf_capability) P_ ((struct font *font));
629 /* Optional.
630 Apply FONT's OTF-FEATURES to the glyph string.
632 FEATURES specifies which OTF features to apply in this format:
633 (SCRIPT LANGSYS GSUB-FEATURE GPOS-FEATURE)
634 See the documentation of `font-drive-otf' for the detail.
636 This method applies the specified features to the codes in the
637 elements of GSTRING-IN (between FROMth and TOth). The output
638 codes are stored in GSTRING-OUT at the IDXth element and the
639 following elements.
641 Return the number of output codes. If none of the features are
642 applicable to the input data, return 0. If GSTRING-OUT is too
643 short, return -1. */
644 int (*otf_drive) P_ ((struct font *font, Lisp_Object features,
645 Lisp_Object gstring_in, int from, int to,
646 Lisp_Object gstring_out, int idx, int alternate_subst));
648 /* Optional.
649 Make the font driver ready for frame F. Usually this function
650 makes some data specific to F and stores it in F by calling
651 font_put_frame_data (). */
652 int (*start_for_frame) P_ ((FRAME_PTR f));
654 /* Optional.
655 End using the driver for frame F. Usually this function free
656 some data stored for F. */
657 int (*end_for_frame) P_ ((FRAME_PTR f));
659 /* Optional.
661 Shape text in GSTRING. See the docstring of
662 `composition-get-gstring' for the format of GSTRING. If the
663 (N+1)th element of GSTRING is nil, input of shaping is from the
664 1st to (N)th elements. In each input glyph, FROM, TO, CHAR, and
665 CODE are already set.
667 This function updates all fields of the input glyphs. If the
668 output glyphs (M) are more than the input glyphs (N), (N+1)th
669 through (M)th elements of GSTRING are updated possibly by making
670 a new glyph object and storing it in GSTRING. If (M) is greater
671 than the length of GSTRING, nil should be return. In that case,
672 this function is called again with the larger GSTRING. */
673 Lisp_Object (*shape) P_ ((Lisp_Object lgstring));
675 /* Optional.
677 If FONT is usable on frame F, return 0. Otherwise return -1.
678 This method is used only for debugging. If this method is NULL,
679 Emacs assumes that the font is usable on any frame. */
680 int (*check) P_ ((FRAME_PTR F, struct font *font));
682 /* Optional.
684 Return the number of variation glyphs of character C supported by
685 FONT. VARIATIONS is an array of 256 elements. If the variation
686 selector N (1..256) defines a glyph, that glyph code is stored in
687 the (N-1)th element of VARIATIONS. */
688 int (*get_variation_glyphs) P_ ((struct font *font,
689 int c, unsigned variations[256]));
691 void (*filter_properties) P_ ((Lisp_Object font, Lisp_Object properties));
693 /* Optional.
695 Return non-zero if FONT_OBJECT can be used as a (cached) font
696 for ENTITY on frame F. */
697 int (*cached_font_ok) P_ ((struct frame *f,
698 Lisp_Object font_object,
699 Lisp_Object entity));
703 /* Chain of font drivers. There's one global font driver list
704 (font_driver_list in font.c). In addition, each frame has it's own
705 font driver list at FRAME_PTR->font_driver_list. */
707 struct font_driver_list
709 /* 1 iff this driver is currently used. It is igonred in the global
710 font driver list.*/
711 int on;
712 /* Pointer to the font driver. */
713 struct font_driver *driver;
714 /* Pointer to the next element of the chain. */
715 struct font_driver_list *next;
719 /* Chain of arbitrary data specific to each font driver. Each frame
720 has it's own font data list at FRAME_PTR->font_data_list. */
722 struct font_data_list
724 /* Pointer to the font driver. */
725 struct font_driver *driver;
726 /* Data specific to the font driver. */
727 void *data;
728 /* Pointer to the next element of the chain. */
729 struct font_data_list *next;
732 EXFUN (Ffont_spec, MANY);
733 EXFUN (Fcopy_font_spec, 1);
734 EXFUN (Fmerge_font_spec, 2);
735 EXFUN (Ffont_get, 2);
736 EXFUN (Ffont_put, 3);
737 EXFUN (Flist_fonts, 4);
738 EXFUN (Ffont_family_list, 1);
739 EXFUN (Fclear_font_cache, 0);
740 EXFUN (Ffont_xlfd_name, 2);
742 extern Lisp_Object font_make_spec P_ ((void));
743 extern Lisp_Object font_make_entity P_ ((void));
744 extern Lisp_Object font_make_object P_ ((int, Lisp_Object, int));
746 extern Lisp_Object find_font_encoding P_ ((Lisp_Object));
747 extern int font_registry_charsets P_ ((Lisp_Object, struct charset **,
748 struct charset **));
749 extern int font_style_to_value P_ ((enum font_property_index prop,
750 Lisp_Object name, int noerror));
751 extern Lisp_Object font_style_symbolic P_ ((Lisp_Object font,
752 enum font_property_index prop,
753 int for_face));
755 extern int font_match_p P_ ((Lisp_Object spec, Lisp_Object font));
756 extern Lisp_Object font_list_entities P_ ((Lisp_Object frame,
757 Lisp_Object spec));
759 extern Lisp_Object font_get_name P_ ((Lisp_Object font_object));
760 extern Lisp_Object font_spec_from_name P_ ((Lisp_Object font_name));
761 extern Lisp_Object font_get_frame P_ ((Lisp_Object font_object));
762 extern int font_has_char P_ ((FRAME_PTR, Lisp_Object, int));
763 extern unsigned font_encode_char P_ ((Lisp_Object, int));
765 extern void font_clear_prop P_ ((Lisp_Object *attrs,
766 enum font_property_index prop));
767 extern void font_update_lface P_ ((FRAME_PTR f, Lisp_Object *attrs));
768 extern Lisp_Object font_find_for_lface P_ ((FRAME_PTR f, Lisp_Object *lface,
769 Lisp_Object spec, int c));
770 extern Lisp_Object font_open_for_lface P_ ((FRAME_PTR f, Lisp_Object entity,
771 Lisp_Object *lface,
772 Lisp_Object spec));
773 extern Lisp_Object font_load_for_lface P_ ((FRAME_PTR f, Lisp_Object *lface,
774 Lisp_Object spec));
775 extern void font_prepare_for_face P_ ((FRAME_PTR f, struct face *face));
776 extern void font_done_for_face P_ ((FRAME_PTR f, struct face *face));
778 extern Lisp_Object font_open_by_spec P_ ((FRAME_PTR f, Lisp_Object spec));
779 extern Lisp_Object font_open_by_name P_ ((FRAME_PTR f, char *name));
780 extern void font_close_object (FRAME_PTR f, Lisp_Object font_object);
782 extern Lisp_Object font_intern_prop P_ ((char *str, int len, int force_symbol));
783 extern void font_update_sort_order P_ ((int *order));
785 extern void font_parse_family_registry P_ ((Lisp_Object family,
786 Lisp_Object registry,
787 Lisp_Object spec));
788 extern Lisp_Object font_spec_from_family_registry P_ ((Lisp_Object family,
789 Lisp_Object registry));
791 extern int font_parse_xlfd P_ ((char *name, Lisp_Object font));
792 extern int font_unparse_xlfd P_ ((Lisp_Object font, int pixel_size,
793 char *name, int bytes));
794 extern int font_parse_fcname P_ ((char *name, Lisp_Object font));
795 extern int font_unparse_fcname P_ ((Lisp_Object font, int pixel_size,
796 char *name, int bytes));
797 extern int font_unparse_gtkname P_ ((Lisp_Object, struct frame *, char *, int));
798 extern void register_font_driver P_ ((struct font_driver *driver, FRAME_PTR f));
799 extern void free_font_driver_list P_ ((FRAME_PTR f));
800 extern Lisp_Object font_update_drivers P_ ((FRAME_PTR f, Lisp_Object list));
801 extern Lisp_Object font_at P_ ((int c, EMACS_INT pos, struct face *face,
802 struct window *w, Lisp_Object object));
803 extern Lisp_Object font_range (EMACS_INT, EMACS_INT *,
804 struct window *, struct face *,
805 Lisp_Object);
806 extern void font_fill_lglyph_metrics P_ ((Lisp_Object, Lisp_Object));
808 extern Lisp_Object font_put_extra P_ ((Lisp_Object font, Lisp_Object prop,
809 Lisp_Object val));
811 extern int font_put_frame_data P_ ((FRAME_PTR f,
812 struct font_driver *driver,
813 void *data));
814 extern void *font_get_frame_data P_ ((FRAME_PTR f,
815 struct font_driver *driver));
817 #ifdef HAVE_FREETYPE
818 extern struct font_driver ftfont_driver;
819 #endif /* HAVE_FREETYPE */
820 #ifdef HAVE_X_WINDOWS
821 extern struct font_driver xfont_driver;
822 extern struct font_driver ftxfont_driver;
823 #ifdef HAVE_XFT
824 extern struct font_driver xftfont_driver;
825 #endif /* HAVE_XFT */
826 #endif /* HAVE_X_WINDOWS */
827 #ifdef WINDOWSNT
828 extern struct font_driver w32font_driver;
829 extern struct font_driver uniscribe_font_driver;
830 #endif /* WINDOWSNT */
831 #ifdef HAVE_NS
832 extern struct font_driver nsfont_driver;
833 #endif /* HAVE_NS */
835 #ifndef FONT_DEBUG
836 #define FONT_DEBUG
837 #endif
839 extern Lisp_Object Vfont_log;
840 extern void font_add_log P_ ((char *, Lisp_Object, Lisp_Object));
841 extern void font_deferred_log P_ ((char *, Lisp_Object, Lisp_Object));
843 #define FONT_ADD_LOG(ACTION, ARG, RESULT) \
844 do { \
845 if (! EQ (Vfont_log, Qt)) \
846 font_add_log ((ACTION), (ARG), (RESULT)); \
847 } while (0)
849 #define FONT_DEFERRED_LOG(ACTION, ARG, RESULT) \
850 do { \
851 if (! EQ (Vfont_log, Qt)) \
852 font_deferred_log ((ACTION), (ARG), (RESULT)); \
853 } while (0)
855 #ifdef FONT_DEBUG
856 #define font_assert(X) do {if (!(X)) abort ();} while (0)
857 #else /* not FONT_DEBUG */
858 #define font_assert(X) (void) 0
859 #endif /* not FONT_DEBUG */
861 #endif /* not EMACS_FONT_H */
863 /* arch-tag: 3b7260c3-5bec-4d6b-a0db-95c1b431b1a2
864 (do not change this comment) */