src/font.h

   1 /* font.h -- Interface definition for font handling.
   2    Copyright (C) 2006, 2007, 2008 Free Software Foundation, Inc.
   3    Copyright (C) 2006, 2007, 2008
   4      National Institute of Advanced Industrial Science and Technology (AIST)
   5      Registration Number H13PRO009
   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 3 of the License, or
  12 (at your option) 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.  If not, see <http://www.gnu.org/licenses/>.  */
  21
  22 #ifndef EMACS_FONT_H
  23 #define EMACS_FONT_H
  24
  25 #include "ccl.h"
  26
  27 /* We have three types of Lisp objects related to font.
  28
  29    FONT-SPEC
  30
  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.
  36
  37    FONT-ENTITY
  38
  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.
  42
  43         Note: Only the method `list' and `match' of a font-driver can
  44         create this object, and should never be modified by Lisp.
  45
  46    FONT-OBJECT
  47
  48         Pseudo vector (length FONT_OBJECT_MAX) of a opend font.
  49
  50         Lisp object encapsulating "struct font".  This corresponds to
  51         an opened font.
  52
  53         Note: Only the method `open' of a font-driver can create this
  54         object, and should never be modified by Lisp.  */
  55
  56 extern Lisp_Object Qfont_spec, Qfont_entity, Qfont_object;
  57
  58
  59 struct font_driver;
  60 struct font;
  61 struct glyph_string;
  62
  63 /* An enumerator for each font property.  This is used as an index to
  64    the vector of FONT-SPEC and FONT-ENTITY.
  65
  66    Note: The order is important and should not be changed.  */
  67
  68 enum font_property_index
  69   {
  70     /* FONT-TYPE is a symbol indicating a font backend; currently `x',
  71        `xft', `ftx' are available on X and gdi on Windows.
  72        For Windows, `bdf' and `uniscribe' backends are in progress.
  73        For Mac OS X, we need `atm'.  */
  74     FONT_TYPE_INDEX,
  75
  76     /* FONT-FOUNDRY is a foundry name (symbol).  */
  77     FONT_FOUNDRY_INDEX,
  78
  79     /* FONT-FAMILY is a family name (symbol).  */
  80     FONT_FAMILY_INDEX,
  81
  82     /* FONT-ADSTYLE is an additional style name (symbol).  */
  83     FONT_ADSTYLE_INDEX,
  84
  85     /* FONT-REGISTRY is a combination of a charset-registry and
  86        charset-encoding name (symbol).  */
  87     FONT_REGISTRY_INDEX,
  88
  89     /* FONT-WEIGHT is a numeric value of weight (e.g. medium, bold) of
  90        the font.  The lowest 8-bit is an index determining the
  91        symbolic name, and the higher bits is the actual numeric value
  92        defined in `font-weight-table'. */
  93     FONT_WEIGHT_INDEX,
  94
  95     /* FONT-SLANT is a numeric value of slant (e.g. r, i, o) of the
  96        font.  The lowest 8-bit is an index determining the symbolic
  97        name, and the higher bits is the actual numeric value defined
  98        in `font-slant-table'.  */
  99     FONT_SLANT_INDEX,
 100
 101     /* FONT-WIDTH is a numeric value of setwidth (e.g. normal) of the
 102        font.  The lowest 8-bit is an index determining the symbolic
 103        name, and the higher bits is the actual numeric value defined
 104        `font-width-table'.  */
 105     FONT_WIDTH_INDEX,
 106
 107     /* FONT-SIZE is a size of the font.  If integer, it is a pixel
 108        size.  For a font-spec, the value can be float specifying a
 109        point size.  The value zero means that the font is
 110        scalable.  */
 111     FONT_SIZE_INDEX,
 112
 113     /* FONT-DPI is a resolution (dot per inch) for which the font is
 114        designed. */
 115     FONT_DPI_INDEX,
 116
 117     /* FONT-SPACING is a spacing (mono, proportional, charcell) of the
 118        font (integer; one of enum font_spacing).  */
 119     FONT_SPACING_INDEX,
 120
 121     /* FONT-AVGWIDTH is an average width (1/10 pixel unit) of the
 122        font.  */
 123     FONT_AVGWIDTH_INDEX,
 124
 125 #if 0
 126     /* The following two members are to substitute for the above 6
 127        members (FONT_WEIGHT_INDEX to FONT_AVGWIDTH_INDEX excluding
 128        FONT_SIZE_INDEX) if it is found that font-entities consumes too
 129        much memory.  */
 130
 131     /* FONT-STYLE is a 24-bit integer containing indices for
 132        style-related properties WEIGHT, SLANT, and WIDTH.  The lowest
 133        8-bit is an indice to the weight table AREF (font_style_table,
 134        0), the next 8-bit is an indice to the slant table AREF
 135        (font_style_table, 1), the highest 8-bit is an indice to the
 136        slant table AREF (font_style_table, 2).  The indice 0 indicates
 137        that the corresponding style is not specified.  This way, we
 138        can represent at most 255 different names for each style, which
 139        is surely sufficient.  */
 140     FONT_STYLE_INDEX,
 141
 142     /* FONT-METRICS is a 27-bit integer containing metrics-related
 143        properties DPI, AVGWIDTH, SPACING.  The lowest 12-bit is for
 144        DPI, the next 12-bit is for AVGWIDTH, the highest 3-bit is for
 145        SPACING.  In each bit field, the highest bit indicates that the
 146        corresponding value is set or not.  This way, we can represent
 147        DPI by 11-bit (0 to 2047), AVGWIDTH by 11-bit (0 to 2047),
 148        SPACING by 3-bit (0 for proportional, 1 for dual, 2 for mono, 3
 149        for charcell), which is surely sufficient.  */
 150     FONT_METRICS_INDEX,
 151 #endif
 152
 153     /* In a font-spec, the value is an alist of extra information of a
 154        font such as name, OpenType features, and language coverage.
 155        In addition, in a font-entity, the value may contain a pair
 156        (font-entity . INFO) where INFO is an extra infomation to
 157        identify a font (font-driver dependent).  */
 158     FONT_EXTRA_INDEX,           /* alist                alist */
 159
 160     /* This value is the length of font-spec vector.  */
 161     FONT_SPEC_MAX,
 162
 163     /* The followings are used only for a font-entity.  */
 164
 165     /* List of font-objects opened from the font-entity.  */
 166     FONT_OBJLIST_INDEX = FONT_SPEC_MAX,
 167
 168     /* This value is the length of font-entity vector.  */
 169     FONT_ENTITY_MAX,
 170
 171     /* XLFD name of the font (string). */
 172     FONT_NAME_INDEX = FONT_ENTITY_MAX,
 173
 174     /* Full name of the font (string).  It is the name extracted from
 175        the opend font, and may be different from the above.  It may be
 176        nil if the opened font doesn't give a name.  */
 177     FONT_FULLNAME_INDEX,
 178
 179     /* File name of the font or nil if a file associated with the font
 180        is not available.  */
 181     FONT_FILE_INDEX,
 182
 183     /* Format of the font (symbol) or nil if unknown.  */
 184     FONT_FORMAT_INDEX,
 185
 186     /* This value is the length of font-object vector.  */
 187     FONT_OBJECT_MAX
 188   };
 189
 190 /* Return the numeric weight value of FONT.  */
 191 #define FONT_WEIGHT_NUMERIC(font)               \
 192   (INTEGERP (AREF ((font), FONT_WEIGHT_INDEX))  \
 193    ? (XINT (AREF ((font), FONT_WEIGHT_INDEX)) >> 8) : -1)
 194 /* Return the numeric slant value of FONT.  */
 195 #define FONT_SLANT_NUMERIC(font)                \
 196   (INTEGERP (AREF ((font), FONT_SLANT_INDEX))   \
 197    ? (XINT (AREF ((font), FONT_SLANT_INDEX)) >> 8) : -1)
 198 /* Return the numeric width value of FONT.  */
 199 #define FONT_WIDTH_NUMERIC(font)                \
 200   (INTEGERP (AREF ((font), FONT_WIDTH_INDEX))   \
 201    ? (XINT (AREF ((font), FONT_WIDTH_INDEX)) >> 8) : -1)
 202 /* Return the symbolic weight value of FONT.  */
 203 #define FONT_WEIGHT_SYMBOLIC(font)      \
 204   font_style_symbolic (font, FONT_WEIGHT_INDEX, 0)
 205 /* Return the symbolic slant value of FONT.  */
 206 #define FONT_SLANT_SYMBOLIC(font)       \
 207   font_style_symbolic (font, FONT_SLANT_INDEX, 0)
 208 /* Return the symbolic width value of FONT.  */
 209 #define FONT_WIDTH_SYMBOLIC(font)       \
 210   font_style_symbolic (font, FONT_WIDTH_INDEX, 0)
 211 /* Return the face-weight corresponding to the weight of FONT.  */
 212 #define FONT_WEIGHT_FOR_FACE(font)      \
 213   font_style_symbolic (font, FONT_WEIGHT_INDEX, 1)
 214 /* Return the face-slant corresponding to the slant of FONT.  */
 215 #define FONT_SLANT_FOR_FACE(font)       \
 216   font_style_symbolic (font, FONT_SLANT_INDEX, 1)
 217 /* Return the face-swidth corresponding to the slant of FONT.  */
 218 #define FONT_WIDTH_FOR_FACE(font)       \
 219   font_style_symbolic (font, FONT_WIDTH_INDEX, 1)
 220
 221 /* Return the numeric weight value corresponding ot the symbol NAME.  */
 222 #define FONT_WEIGHT_NAME_NUMERIC(name)  \
 223   (font_style_to_value (FONT_WEIGHT_INDEX, (name), 0) >> 8)
 224 /* Return the numeric slant value corresponding ot the symbol NAME.  */
 225 #define FONT_SLANT_NAME_NUMERIC(name)   \
 226   (font_style_to_value (FONT_SLANT_INDEX, (name), 0) >> 8)
 227 /* Return the numeric width value corresponding ot the symbol NAME.  */
 228 #define FONT_WIDTH_NAME_NUMERIC(name)   \
 229   (font_style_to_value (FONT_WIDTH_INDEX, (name), 0) >> 8)
 230
 231 /* Set the font property PROP of FONT to VAL.  PROP is one of
 232    style-related font property index (FONT_WEIGHT/SLANT/WIDTH_INDEX).
 233    VAL (integer or symbol) is the numeric or symbolic style value.  */
 234 #define FONT_SET_STYLE(font, prop, val) \
 235   ASET ((font), prop, make_number (font_style_to_value (prop, val, 1)))
 236
 237 extern Lisp_Object QCspacing, QCdpi, QCscalable, QCotf, QClang, QCscript;
 238 extern Lisp_Object QCavgwidth, QCfont_entity, QCfc_unknown_spec;
 239
 240 /* Important character set symbols.  */
 241 extern Lisp_Object Qiso8859_1, Qiso10646_1, Qunicode_bmp, Qunicode_sip;
 242
 243 /* Structure for a font-spec.  */
 244
 245 struct font_spec
 246 {
 247   EMACS_UINT size;
 248   struct Lisp_Vector *next;
 249   Lisp_Object props[FONT_SPEC_MAX];
 250 };
 251
 252 /* Structure for a font-entity.  */
 253
 254 struct font_entity
 255 {
 256   EMACS_UINT size;
 257   struct Lisp_Vector *next;
 258   Lisp_Object props[FONT_ENTITY_MAX];
 259 };
 260
 261 /* A value which may appear in the member `encoding' of struct font
 262    indicating that a font itself doesn't tell which encoding to be
 263    used.  */
 264 #define FONT_ENCODING_NOT_DECIDED 255
 265
 266 /* Structure for a font-object.  */
 267
 268 struct font
 269 {
 270   EMACS_UINT size;
 271   struct Lisp_Vector *next;
 272
 273   /* All Lisp_Object components must come first.
 274      That ensures they are all aligned normally.  */
 275
 276   Lisp_Object props[FONT_OBJECT_MAX];
 277
 278   /* Beyond here, there should be no more Lisp_Object components.  */
 279
 280   /* Maximum bound width over all existing characters of the font.  On
 281      X window, this is same as (font->max_bounds.width).  */
 282   int max_width;
 283
 284   /* By which pixel size the font is opened.  */
 285   int pixel_size;
 286
 287   /* Height of the font.  On X window, this is the same as
 288      (font->ascent + font->descent).  */
 289   int height;
 290
 291   /* Width of the space glyph of the font.  If the font doesn't have a
 292      SPACE glyph, the value is 0.  */
 293   int space_width;
 294
 295   /* Average width of glyphs in the font.  If the font itself doesn't
 296      have that information but has glyphs of ASCII character, the
 297      value is the average with of those glyphs.  Otherwise, the value
 298      is 0.  */
 299   int average_width;
 300
 301   /* Minimum glyph width (in pixels).  */
 302   int min_width;
 303
 304   /* Ascent and descent of the font (in pixels).  */
 305   int ascent, descent;
 306
 307   /* Vertical pixel width of the underline.  If is zero if that
 308      information is not in the font.  */
 309   int underline_thickness;
 310
 311   /* Vertical pixel position (relative to the baseline) of the
 312      underline.  If it is positive, it is below the baseline.  It is
 313      negative if that information is not in the font.  */
 314   int underline_position;
 315
 316   /* 1 if `vertical-centering-font-regexp' matches this font name.
 317      In this case, we render characters at vartical center positions
 318      of lines.  */
 319   int vertical_centering;
 320
 321   /* Encoding type of the font.  The value is one of
 322      0, 1, 2, or 3:
 323         0: code points 0x20..0x7F or 0x2020..0x7F7F are used
 324         1: code points 0xA0..0xFF or 0xA0A0..0xFFFF are used
 325         2: code points 0x20A0..0x7FFF are used
 326         3: code points 0xA020..0xFF7F are used
 327      If the member `font_encoder' is not NULL, this member is ignored.  */
 328   unsigned char encoding_type;
 329
 330   /* The baseline position of a font is normally `ascent' value of the
 331      font.  However, there exists many fonts which don't set `ascent'
 332      an appropriate value to be used as baseline position.  This is
 333      typical in such ASCII fonts which are designed to be used with
 334      Chinese, Japanese, Korean characters.  When we use mixture of
 335      such fonts and normal fonts (having correct `ascent' value), a
 336      display line gets very ugly.  Since we have no way to fix it
 337      automatically, it is users responsibility to supply well designed
 338      fonts or correct `ascent' value of fonts.  But, the latter
 339      requires heavy work (modifying all bitmap data in BDF files).
 340      So, Emacs accepts a private font property
 341      `_MULE_BASELINE_OFFSET'.  If a font has this property, we
 342      calculate the baseline position by subtracting the value from
 343      `ascent'.  In other words, the value indicates how many bits
 344      higher we should draw a character of the font than normal ASCII
 345      text for a better looking.
 346
 347      We also have to consider the fact that the concept of `baseline'
 348      differs among scripts to which each character belongs.  For
 349      instance, baseline should be at the bottom most position of all
 350      glyphs for Chinese, Japanese, and Korean.  But, many of existing
 351      fonts for those characters doesn't have correct `ascent' values
 352      because they are designed to be used with ASCII fonts.  To
 353      display characters of different language on the same line, the
 354      best way will be to arrange them in the middle of the line.  So,
 355      in such a case, again, we utilize the font property
 356      `_MULE_BASELINE_OFFSET'.  If the value is larger than `ascent' we
 357      calculate baseline so that a character is arranged in the middle
 358      of a line.  */
 359   int baseline_offset;
 360
 361   /* Non zero means a character should be composed at a position
 362      relative to the height (or depth) of previous glyphs in the
 363      following cases:
 364         (1) The bottom of the character is higher than this value.  In
 365         this case, the character is drawn above the previous glyphs.
 366         (2) The top of the character is lower than 0 (i.e. baseline
 367         height).  In this case, the character is drawn beneath the
 368         previous glyphs.
 369
 370      This value is taken from a private font property
 371      `_MULE_RELATIVE_COMPOSE' which is introduced by Emacs.  */
 372   int relative_compose;
 373
 374   /* Non zero means an ascent value to be used for a character
 375      registered in char-table `use-default-ascent'.  */
 376   int default_ascent;
 377
 378   /* CCL program to calculate code points of the font.  */
 379   struct ccl_program *font_encoder;
 380
 381   /* Font-driver for the font.  */
 382   struct font_driver *driver;
 383
 384   /* Charset to encode a character code into a glyph code of the font.
 385      -1 means that the font doesn't require this information to encode
 386      a character.  */
 387   int encoding_charset;
 388
 389   /* Charset to check if a character code is supported by the font.
 390      -1 means that the contents of the font must be looked up to
 391      determine it.  */
 392   int repertory_charset;
 393
 394   /* There will be more to this structure, but they are private to a
 395      font-driver.  */
 396 };
 397
 398 enum font_spacing
 399   {
 400     FONT_SPACING_PROPORTIONAL = 0,
 401     FONT_SPACING_DUAL = 90,
 402     FONT_SPACING_MONO = 100,
 403     FONT_SPACING_CHARCELL = 110
 404   };
 405
 406 struct font_metrics
 407 {
 408   short lbearing, rbearing, width, ascent, descent;
 409 };
 410
 411 struct font_bitmap
 412 {
 413   int bits_per_pixel;
 414   int rows;
 415   int width;
 416   int pitch;
 417   unsigned char *buffer;
 418   int left;
 419   int top;
 420   int advance;
 421   void *extra;
 422 };
 423
 424 /* Predicates to check various font-related objects.  */
 425
 426 /* 1 iff X is one of font-spec, font-entity, and font-object.  */
 427 #define FONTP(x) PSEUDOVECTORP (x, PVEC_FONT)
 428 /* 1 iff X is font-spec.  */
 429 #define FONT_SPEC_P(x)  \
 430   (FONTP (x) && (ASIZE (x) & PSEUDOVECTOR_SIZE_MASK) == FONT_SPEC_MAX)
 431 /* 1 iff X is font-entity.  */
 432 #define FONT_ENTITY_P(x)        \
 433   (FONTP (x) && (ASIZE (x) & PSEUDOVECTOR_SIZE_MASK) == FONT_ENTITY_MAX)
 434 /* 1 iff X is font-object.  */
 435 #define FONT_OBJECT_P(x)        \
 436   (FONTP (x) && (ASIZE (x) & PSEUDOVECTOR_SIZE_MASK) == FONT_OBJECT_MAX)
 437
 438 /* 1 iff ENTITY can't be loaded.  */
 439 #define FONT_ENTITY_NOT_LOADABLE(entity)        \
 440   EQ (AREF (entity, FONT_OBJLIST_INDEX), Qt)
 441
 442 /* Flag ENTITY not loadable.  */
 443 #define FONT_ENTITY_SET_NOT_LOADABLE(entity)    \
 444   ASET (entity, FONT_OBJLIST_INDEX, Qt)
 445
 446
 447 /* Check macros for various font-related objects.  */
 448
 449 #define CHECK_FONT(x)   \
 450   do { if (! FONTP (x)) wrong_type_argument (Qfont, x); } while (0)
 451 #define CHECK_FONT_SPEC(x)      \
 452   do { if (! FONT_SPEC_P (x)) wrong_type_argument (Qfont_spec, x); } while (0)
 453 #define CHECK_FONT_ENTITY(x)    \
 454   do { if (! FONT_ENTITY_P (x)) wrong_type_argument (Qfont_entity, x); } while (0)
 455 #define CHECK_FONT_OBJECT(x)    \
 456   do { if (! FONT_OBJECT_P (x)) wrong_type_argument (Qfont_object, x); } while (0)
 457
 458 #define CHECK_FONT_GET_OBJECT(x, font)  \
 459   do {                                  \
 460     CHECK_FONT_OBJECT (x);              \
 461     font = XFONT_OBJECT (x);            \
 462   } while (0)
 463
 464 #define XFONT_SPEC(p)   \
 465   (eassert (FONT_SPEC_P(p)), (struct font_spec *) XPNTR (p))
 466 #define XFONT_ENTITY(p) \
 467   (eassert (FONT_ENTITY_P(p)), (struct font_entity *) XPNTR (p))
 468 #define XFONT_OBJECT(p) \
 469   (eassert (FONT_OBJECT_P(p)), (struct font *) XPNTR (p))
 470 #define XSETFONT(a, b) (XSETPSEUDOVECTOR (a, b, PVEC_FONT))
 471
 472 /* Number of pt per inch (from the TeXbook).  */
 473 #define PT_PER_INCH 72.27
 474
 475 /* Return a pixel size (integer) corresponding to POINT size (double)
 476    on resolution DPI.  */
 477 #define POINT_TO_PIXEL(POINT, DPI) ((POINT) * (DPI) / PT_PER_INCH + 0.5)
 478
 479 /* Return a point size (double) corresponding to POINT size (integer)
 480    on resolution DPI.  */
 481 #define PIXEL_TO_POINT(PIXEL, DPI) ((PIXEL) * PT_PER_INCH / (DPI) + 0.5)
 482
 483 /* Ignore the difference of font pixel sizes less than or equal to
 484    this value.  */
 485 #define FONT_PIXEL_SIZE_QUANTUM 1
 486
 487 struct face;
 488 struct composition;
 489
 490 /* Macros for lispy glyph-string.  */
 491 enum lgstring_indices
 492   {
 493     LGSTRING_IX_FONT, LGSTRING_IX_WIDTH,
 494     LGSTRING_IX_LBEARING, LGSTRING_IX_RBEARING,
 495     LGSTRING_IX_ASCENT, LGSTRING_IX_DESCENT
 496   };
 497 #define LGSTRING_SLOT(lgs, ix) AREF (AREF ((lgs), 0), ix)
 498 #define LGSTRING_FONT(lgs) LGSTRING_SLOT (lgs, LGSTRING_IX_FONT)
 499 #define LGSTRING_WIDTH(lgs) XINT (LGSTRING_SLOT (lgs, LGSTRING_IX_WIDTH))
 500 #define LGSTRING_LBEARING(lgs) XINT (LGSTRING_SLOT (lgs, LGSTRING_IX_LBEARING))
 501 #define LGSTRING_RBEARING(lgs) XINT (LGSTRING_SLOT (lgs, LGSTRING_IX_RBEARING))
 502 #define LGSTRING_ASCENT(lgs) XINT (LGSTRING_SLOT (lgs, LGSTRING_IX_ASCENT))
 503 #define LGSTRING_DESCENT(lgs) XINT (LGSTRING_SLOT (lgs, LGSTRING_IX_DESCENT))
 504 #define LGSTRING_SET_SLOT(lgs, ix, val) ASET (AREF ((lgs), 0), ix, (val))
 505 #define LGSTRING_SET_FONT(lgs, val)     \
 506   LGSTRING_SET_SLOT(lgs, LGSTRING_IX_FONT, (val))
 507 #define LGSTRING_SET_WIDTH(lgs, val)    \
 508   LGSTRING_SET_SLOT(lgs, LGSTRING_IX_WIDTH, make_number (val))
 509 #define LGSTRING_SET_LBEARING(lgs, val) \
 510   LGSTRING_SET_SLOT(lgs, LGSTRING_IX_LBEARING, make_number (val))
 511 #define LGSTRING_SET_RBEARING(lgs, val) \
 512   LGSTRING_SET_SLOT(lgs, LGSTRING_IX_RBEARING, make_number (val))
 513 #define LGSTRING_SET_ASCENT(lgs, val)   \
 514   LGSTRING_SET_SLOT(lgs, LGSTRING_IX_ASCENT, make_number (val))
 515 #define LGSTRING_SET_DESCENT(lgs, val)  \
 516   LGSTRING_SET_SLOT(lgs, LGSTRING_IX_DESCENT, make_number (val))
 517
 518 #define LGSTRING_LENGTH(lgs) (ASIZE ((lgs)) - 1)
 519 #define LGSTRING_GLYPH(lgs, idx) AREF ((lgs), (idx) + 1)
 520 #define LGSTRING_SET_GLYPH(lgs, idx, val) ASET ((lgs), (idx) + 1, (val))
 521
 522 /* Vector size of Lispy glyph.  */
 523 enum lglyph_indices
 524   {
 525     LGLYPH_IX_FROM, LGLYPH_IX_TO,  LGLYPH_IX_CHAR, LGLYPH_IX_CODE,
 526     LGLYPH_IX_WIDTH, LGLYPH_IX_LBEARING, LGLYPH_IX_RBEARING,
 527     LGLYPH_IX_ASCENT, LGLYPH_IX_DESCENT, LGLYPH_IX_ADJUSTMENT,
 528     /* Not an index.  */
 529     LGLYPH_SIZE
 530   };
 531 #define LGLYPH_FROM(g) XINT (AREF ((g), LGLYPH_IX_FROM))
 532 #define LGLYPH_TO(g) XINT (AREF ((g), LGLYPH_IX_TO))
 533 #define LGLYPH_CHAR(g) XINT (AREF ((g), LGLYPH_IX_CHAR))
 534 #define LGLYPH_CODE(g) XUINT (AREF ((g), LGLYPH_IX_CODE))
 535 #define LGLYPH_WIDTH(g) XINT (AREF ((g), LGLYPH_IX_WIDTH))
 536 #define LGLYPH_LBEARING(g) XINT (AREF ((g), LGLYPH_IX_LBEARING))
 537 #define LGLYPH_RBEARING(g) XINT (AREF ((g), LGLYPH_IX_RBEARING))
 538 #define LGLYPH_ASCENT(g) XINT (AREF ((g), LGLYPH_IX_ASCENT))
 539 #define LGLYPH_DESCENT(g) XINT (AREF ((g), LGLYPH_IX_DESCENT))
 540 #define LGLYPH_ADJUSTMENT(g) AREF ((g), LGLYPH_IX_ADJUSTMENT)
 541 #define LGLYPH_SET_FROM(g, val) ASET ((g), LGLYPH_IX_FROM, make_number (val))
 542 #define LGLYPH_SET_TO(g, val) ASET ((g), LGLYPH_IX_TO, make_number (val))
 543 #define LGLYPH_SET_CHAR(g, val) ASET ((g), LGLYPH_IX_CHAR, make_number (val))
 544 /* FIXME: we should use make_uint_number here.  */
 545 #define LGLYPH_SET_CODE(g, val) ASET ((g), LGLYPH_IX_CODE, make_number (val))
 546 #define LGLYPH_SET_WIDTH(g, val) ASET ((g), LGLYPH_IX_WIDTH, make_number (val))
 547 #define LGLYPH_SET_LBEARING(g, val) ASET ((g), LGLYPH_IX_RBEARING, make_number (val))
 548 #define LGLYPH_SET_RBEARING(g, val) ASET ((g), LGLYPH_IX_LBEARING, make_number (val))
 549 #define LGLYPH_SET_ASCENT(g, val) ASET ((g), LGLYPH_IX_ASCENT, make_number (val))
 550 #define LGLYPH_SET_DESCENT(g, val) ASET ((g), LGLYPH_IX_DESCENT, make_number (val))
 551 #define LGLYPH_SET_ADJUSTMENT(g, val) ASET ((g), LGLYPH_IX_ADJUSTMENT, (val))
 552
 553 #define LGLYPH_XOFF(g) (VECTORP (LGLYPH_ADJUSTMENT (g)) \
 554                         ? XINT (AREF (LGLYPH_ADJUSTMENT (g), 0)) : 0)
 555 #define LGLYPH_YOFF(g) (VECTORP (LGLYPH_ADJUSTMENT (g)) \
 556                         ? XINT (AREF (LGLYPH_ADJUSTMENT (g), 1)) : 0)
 557 #define LGLYPH_WADJUST(g) (VECTORP (LGLYPH_ADJUSTMENT (g)) \
 558                            ? XINT (AREF (LGLYPH_ADJUSTMENT (g), 2)) : 0)
 559
 560 #define FONT_INVALID_CODE 0xFFFFFFFF
 561
 562 /* Font driver.  Members specified as "optional" can be NULL.  */
 563
 564 struct font_driver
 565 {
 566   /* Symbol indicating the type of the font-driver.  */
 567   Lisp_Object type;
 568
 569   /* 1 iff the font's foundary, family, and adstyle names are case
 570      sensitve.  */
 571   int case_sensitive;
 572
 573   /* Return a cache of font-entities on frame F.  The cache must be a
 574      cons whose cdr part is the actual cache area.  */
 575   Lisp_Object (*get_cache) P_ ((FRAME_PTR F));
 576
 577   /* List fonts exactly matching with FONT_SPEC on FRAME.  The value
 578      is a list of font-entities.  It is assured that the properties
 579      WEIGHT to AVGWIDTH are all nil (i.e. not specified) in FONT_SPEC.
 580      This and the following `match' are the only APIs that allocate
 581      font-entities.  */
 582   Lisp_Object (*list) P_ ((Lisp_Object frame, Lisp_Object font_spec));
 583
 584   /* Return a font entity most closely maching with FONT_SPEC on
 585      FRAME.  The closeness is detemined by the font backend, thus
 586      `face-font-selection-order' is ignored here.  */
 587   Lisp_Object (*match) P_ ((Lisp_Object frame, Lisp_Object font_spec));
 588
 589   /* Optional.
 590      List available families.  The value is a list of family names
 591      (symbols).  */
 592   Lisp_Object (*list_family) P_ ((Lisp_Object frame));
 593
 594   /* Optional (if FONT_EXTRA_INDEX is not Lisp_Save_Value).
 595      Free FONT_EXTRA_INDEX field of FONT_ENTITY.  */
 596   void (*free_entity) P_ ((Lisp_Object font_entity));
 597
 598   /* Open a font specified by FONT_ENTITY on frame F.  If the font is
 599      scalable, open it with PIXEL_SIZE.  */
 600   Lisp_Object (*open) P_ ((FRAME_PTR f, Lisp_Object font_entity,
 601                            int pixel_size));
 602
 603   /* Close FONT on frame F.  */
 604   void (*close) P_ ((FRAME_PTR f, struct font *font));
 605
 606   /* Optional (if FACE->extra is not used).
 607      Prepare FACE for displaying characters by FONT on frame F by
 608      storing some data in FACE->extra.  If successful, return 0.
 609      Otherwise, return -1.  */
 610   int (*prepare_face) P_ ((FRAME_PTR f, struct face *face));
 611
 612   /* Optional.
 613      Done FACE for displaying characters by FACE->font on frame F.  */
 614   void (*done_face) P_ ((FRAME_PTR f, struct face *face));
 615
 616   /* Optional.
 617      If FONT_ENTITY has a glyph for character C (Unicode code point),
 618      return 1.  If not, return 0.  If a font must be opened to check
 619      it, return -1.  */
 620   int (*has_char) P_ ((Lisp_Object entity, int c));
 621
 622   /* Return a glyph code of FONT for characer C (Unicode code point).
 623      If FONT doesn't have such a glyph, return FONT_INVALID_CODE.  */
 624   unsigned (*encode_char) P_ ((struct font *font, int c));
 625
 626   /* Computate the total metrics of the NGLYPHS glyphs specified by
 627      the font FONT and the sequence of glyph codes CODE, and store the
 628      result in METRICS.  */
 629   int (*text_extents) P_ ((struct font *font,
 630                            unsigned *code, int nglyphs,
 631                            struct font_metrics *metrics));
 632
 633   /* Optional.
 634      Draw glyphs between FROM and TO of S->char2b at (X Y) pixel
 635      position of frame F with S->FACE and S->GC.  If WITH_BACKGROUND
 636      is nonzero, fill the background in advance.  It is assured that
 637      WITH_BACKGROUND is zero when (FROM > 0 || TO < S->nchars).  */
 638   int (*draw) P_ ((struct glyph_string *s, int from, int to,
 639                    int x, int y, int with_background));
 640
 641   /* Optional.
 642      Store bitmap data for glyph-code CODE of FONT in BITMAP.  It is
 643      intended that this method is callled from the other font-driver
 644      for actual drawing.  */
 645   int (*get_bitmap) P_ ((struct font *font, unsigned code,
 646                          struct font_bitmap *bitmap,
 647                          int bits_per_pixel));
 648
 649   /* Optional.
 650      Free bitmap data in BITMAP.  */
 651   void (*free_bitmap) P_ ((struct font *font, struct font_bitmap *bitmap));
 652
 653   /* Optional.
 654      Return an outline data for glyph-code CODE of FONT.  The format
 655      of the outline data depends on the font-driver.  */
 656   void *(*get_outline) P_ ((struct font *font, unsigned code));
 657
 658   /* Optional.
 659      Free OUTLINE (that is obtained by the above method).  */
 660   void (*free_outline) P_ ((struct font *font, void *outline));
 661
 662   /* Optional.
 663      Get coordinates of the INDEXth anchor point of the glyph whose
 664      code is CODE.  Store the coordinates in *X and *Y.  Return 0 if
 665      the operations was successfull.  Otherwise return -1.  */
 666   int (*anchor_point) P_ ((struct font *font, unsigned code, int index,
 667                            int *x, int *y));
 668
 669   /* Optional.
 670      Return a list describing which scripts/languages FONT
 671      supports by which GSUB/GPOS features of OpenType tables.  */
 672   Lisp_Object (*otf_capability) P_ ((struct font *font));
 673
 674   /* Optional.
 675      Apply FONT's OTF-FEATURES to the glyph string.
 676
 677      FEATURES specifies which OTF features to apply in this format:
 678         (SCRIPT LANGSYS GSUB-FEATURE GPOS-FEATURE)
 679      See the documentation of `font-drive-otf' for the detail.
 680
 681      This method applies the specified features to the codes in the
 682      elements of GSTRING-IN (between FROMth and TOth).  The output
 683      codes are stored in GSTRING-OUT at the IDXth element and the
 684      following elements.
 685
 686      Return the number of output codes.  If none of the features are
 687      applicable to the input data, return 0.  If GSTRING-OUT is too
 688      short, return -1.  */
 689   int (*otf_drive) P_ ((struct font *font, Lisp_Object features,
 690                        Lisp_Object gstring_in, int from, int to,
 691                        Lisp_Object gstring_out, int idx, int alternate_subst));
 692
 693   /* Optional.
 694      Make the font driver ready for frame F.  Usually this function
 695      makes some data specific to F and store it in F by calling
 696      font_put_frame_data ().  */
 697   int (*start_for_frame) P_ ((FRAME_PTR f));
 698
 699   /* Optional.
 700      End using the driver for frame F.  Usually this function free
 701      some data stored for F.  */
 702   int (*end_for_frame) P_ ((FRAME_PTR f));
 703
 704   /* Optional.
 705
 706      Shape text in LGSTRING.  See the docstring of `font-make-gstring'
 707      for the format of LGSTRING.  If the (N+1)th element of LGSTRING
 708      is nil, input of shaping is from the 1st to (N)th elements.  In
 709      each input glyph, FROM, TO, CHAR, and CODE are already set.
 710
 711      This function updates all fields of the input glyphs.  If the
 712      output glyphs (M) are more than the input glyphs (N), (N+1)th
 713      through (M)th elements of LGSTRING are updated possibly by making
 714      a new glyph object and storing it in LGSTRING.  If (M) is greater
 715      than the length of LGSTRING, nil should be return.  In that case,
 716      this function is called again with the larger LGSTRING.  */
 717   Lisp_Object (*shape) P_ ((Lisp_Object lgstring));
 718
 719   /* Optional.
 720
 721      If FONT is usable on frame F, return 0.  Otherwise return -1.
 722    */
 723   int (*check) P_ ((FRAME_PTR F, struct font *font));
 724 };
 725
 726
 727 /* Chain of font drivers.  There's one global font driver list
 728    (font_driver_list in font.c).  In addition, each frame has it's own
 729    font driver list at FRAME_PTR->font_driver_list.  */
 730
 731 struct font_driver_list
 732 {
 733   /* 1 iff this driver is currently used.  It is igonred in the global
 734      font driver list.*/
 735   int on;
 736   /* Pointer to the font driver.  */
 737   struct font_driver *driver;
 738   /* Pointer to the next element of the chain.  */
 739   struct font_driver_list *next;
 740 };
 741
 742
 743 /* Chain of arbitrary data specific to each font driver.  Each frame
 744    has it's own font data list at FRAME_PTR->font_data_list.  */
 745
 746 struct font_data_list
 747 {
 748   /* Pointer to the font driver.  */
 749   struct font_driver *driver;
 750   /* Data specific to the font driver.  */
 751   void *data;
 752   /* Pointer to the next element of the chain.  */
 753   struct font_data_list *next;
 754 };
 755
 756 EXFUN (Ffont_spec, MANY);
 757 EXFUN (Fcopy_font_spec, 1);
 758 EXFUN (Fmerge_font_spec, 2);
 759 EXFUN (Ffont_get, 2);
 760 EXFUN (Ffont_put, 3);
 761 EXFUN (Flist_fonts, 4);
 762 EXFUN (Ffont_family_list, 1);
 763 EXFUN (Fclear_font_cache, 0);
 764 EXFUN (Ffont_xlfd_name, 2);
 765
 766 extern Lisp_Object font_make_spec P_ ((void));
 767 extern Lisp_Object font_make_entity P_ ((void));
 768 extern Lisp_Object font_make_object P_ ((int));
 769
 770 extern Lisp_Object find_font_encoding P_ ((Lisp_Object));
 771 extern int font_registry_charsets P_ ((Lisp_Object, struct charset **,
 772                                        struct charset **));
 773 extern int font_style_to_value P_ ((enum font_property_index prop,
 774                                     Lisp_Object name, int noerror));
 775 extern Lisp_Object font_style_symbolic P_ ((Lisp_Object font,
 776                                             enum font_property_index prop,
 777                                             int for_face));
 778
 779 extern int font_match_p P_ ((Lisp_Object spec, Lisp_Object entity));
 780 extern Lisp_Object font_list_entities P_ ((Lisp_Object frame,
 781                                            Lisp_Object spec));
 782
 783 extern Lisp_Object font_get_name P_ ((Lisp_Object font_object));
 784 extern Lisp_Object font_spec_from_name P_ ((Lisp_Object font_name));
 785 extern Lisp_Object font_get_frame P_ ((Lisp_Object font_object));
 786 extern int font_has_char P_ ((FRAME_PTR, Lisp_Object, int));
 787 extern unsigned font_encode_char P_ ((Lisp_Object, int));
 788
 789 extern void font_clear_prop P_ ((Lisp_Object *attrs,
 790                                  enum font_property_index prop));
 791 extern void font_update_lface P_ ((FRAME_PTR f, Lisp_Object *attrs));
 792 extern Lisp_Object font_find_for_lface P_ ((FRAME_PTR f, Lisp_Object *lface,
 793                                             Lisp_Object spec, int c));
 794 extern Lisp_Object font_open_for_lface P_ ((FRAME_PTR f, Lisp_Object entity,
 795                                             Lisp_Object *lface,
 796                                             Lisp_Object spec));
 797 extern Lisp_Object font_load_for_lface P_ ((FRAME_PTR f, Lisp_Object *lface,
 798                                             Lisp_Object spec));
 799 extern void font_prepare_for_face P_ ((FRAME_PTR f, struct face *face));
 800 extern void font_done_for_face P_ ((FRAME_PTR f, struct face *face));
 801
 802 extern Lisp_Object font_open_by_name P_ ((FRAME_PTR f, char *name));
 803 extern void font_close_object (FRAME_PTR f, Lisp_Object font_object);
 804
 805 extern Lisp_Object font_intern_prop P_ ((char *str, int len));
 806 extern void font_update_sort_order P_ ((int *order));
 807
 808 extern void font_parse_family_registry P_ ((Lisp_Object family,
 809                                             Lisp_Object registry,
 810                                             Lisp_Object spec));
 811 extern Lisp_Object font_spec_from_family_registry P_ ((Lisp_Object family,
 812                                                        Lisp_Object registry));
 813
 814 extern int font_parse_xlfd P_ ((char *name, Lisp_Object font));
 815 extern int font_unparse_xlfd P_ ((Lisp_Object font, int pixel_size,
 816                                   char *name, int bytes));
 817 extern int font_parse_fcname P_ ((char *name, Lisp_Object font));
 818 extern int font_unparse_fcname P_ ((Lisp_Object font, int pixel_size,
 819                                   char *name, int bytes));
 820 extern void register_font_driver P_ ((struct font_driver *driver, FRAME_PTR f));
 821 extern void free_font_driver_list P_ ((FRAME_PTR f));
 822 extern Lisp_Object font_update_drivers P_ ((FRAME_PTR f, Lisp_Object list));
 823 extern Lisp_Object font_at P_ ((int c, EMACS_INT pos, struct face *face,
 824                                 struct window *w, Lisp_Object object));
 825 extern EMACS_INT font_range P_ ((EMACS_INT pos, EMACS_INT limit,
 826                                  struct face *face, FRAME_PTR f,
 827                                  Lisp_Object object));
 828
 829 extern struct font *font_prepare_composition P_ ((struct composition *cmp,
 830                                                   FRAME_PTR f));
 831
 832 extern Lisp_Object font_put_extra P_ ((Lisp_Object font, Lisp_Object prop,
 833                                        Lisp_Object val));
 834
 835 extern int font_put_frame_data P_ ((FRAME_PTR f,
 836                                     struct font_driver *driver,
 837                                     void *data));
 838 extern void *font_get_frame_data P_ ((FRAME_PTR f,
 839                                       struct font_driver *driver));
 840
 841 #ifdef HAVE_FREETYPE
 842 extern struct font_driver ftfont_driver;
 843 #endif  /* HAVE_FREETYPE */
 844 #ifdef HAVE_X_WINDOWS
 845 extern struct font_driver xfont_driver;
 846 extern struct font_driver ftxfont_driver;
 847 #ifdef HAVE_XFT
 848 extern struct font_driver xftfont_driver;
 849 #endif  /* HAVE_XFT */
 850 #endif  /* HAVE_X_WINDOWS */
 851 #ifdef WINDOWSNT
 852 extern struct font_driver w32font_driver;
 853 extern struct font_driver uniscribe_font_driver;
 854 #endif  /* WINDOWSNT */
 855 #ifdef MAC_OS
 856 extern struct font_driver atmfont_driver;
 857 #endif  /* MAC_OS */
 858
 859 #ifndef FONT_DEBUG
 860 #define FONT_DEBUG
 861 #endif
 862
 863 extern void font_add_log P_ ((char *, Lisp_Object, Lisp_Object));
 864
 865 #ifdef FONT_DEBUG
 866 #define font_assert(X)  do {if (!(X)) abort ();} while (0)
 867 #else  /* not FONT_DEBUG */
 868 #define font_assert(X)  (void) 0
 869 #endif  /* not FONT_DEBUG */
 870
 871 #endif  /* not EMACS_FONT_H */
 872
 873 /* arch-tag: 3b7260c3-5bec-4d6b-a0db-95c1b431b1a2
 874    (do not change this comment) */