src/composite.h

   1 /* Header for composite sequence handler.
   2    Copyright (C) 2001-2012 Free Software Foundation, Inc.
   3    Copyright (C) 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
   4      National Institute of Advanced Industrial Science and Technology (AIST)
   5      Registration Number H14PRO021
   6    Copyright (C) 2003, 2006
   7      National Institute of Advanced Industrial Science and Technology (AIST)
   8      Registration Number H13PRO009
   9
  10 This file is part of GNU Emacs.
  11
  12 GNU Emacs is free software: you can redistribute it and/or modify
  13 it under the terms of the GNU General Public License as published by
  14 the Free Software Foundation, either version 3 of the License, or
  15 (at your option) any later version.
  16
  17 GNU Emacs is distributed in the hope that it will be useful,
  18 but WITHOUT ANY WARRANTY; without even the implied warranty of
  19 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20 GNU General Public License for more details.
  21
  22 You should have received a copy of the GNU General Public License
  23 along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
  24
  25 #ifndef EMACS_COMPOSITE_H
  26 #define EMACS_COMPOSITE_H
  27
  28 INLINE_HEADER_BEGIN
  29 #ifndef COMPOSITE_INLINE
  30 # define COMPOSITE_INLINE INLINE
  31 #endif
  32
  33 /* Methods to display a sequence of components of a composition.  */
  34 enum composition_method {
  35   /* Compose relatively without alternate characters.  */
  36   COMPOSITION_RELATIVE,
  37   /* Compose by specified composition rules.  This is not used in
  38      Emacs 21 but we need it to decode files saved in the older
  39      versions of Emacs.  */
  40   COMPOSITION_WITH_RULE,
  41   /* Compose relatively with alternate characters.  */
  42   COMPOSITION_WITH_ALTCHARS,
  43   /* Compose by specified composition rules with alternate characters.  */
  44   COMPOSITION_WITH_RULE_ALTCHARS,
  45   /* This is not a method.  */
  46   COMPOSITION_NO
  47 };
  48
  49 /* Maximum number of components a single composition can have.  */
  50 #define MAX_COMPOSITION_COMPONENTS 16
  51
  52 /* These macros access information about a composition that
  53    has `composition' property PROP.  PROP is:
  54         ((LENGTH . COMPONENTS) . MODIFICATION-FUNC)
  55    or
  56         (COMPOSITION-ID . (LENGTH COMPONENTS . MODIFICATION-FUNC))
  57    They don't check validity of PROP.  */
  58
  59 /* Temporary variable used only in the following macros.  */
  60 extern Lisp_Object composition_temp;
  61
  62 /* Return 1 if the composition is already registered.  */
  63 #define COMPOSITION_REGISTERD_P(prop) INTEGERP (XCAR (prop))
  64
  65 /* Return ID number of the already registered composition.  */
  66 #define COMPOSITION_ID(prop) XINT (XCAR (prop))
  67
  68 /* Return length of the composition.  */
  69 #define COMPOSITION_LENGTH(prop)        \
  70   (COMPOSITION_REGISTERD_P (prop)       \
  71    ? XINT (XCAR (XCDR (prop)))          \
  72    : XINT (XCAR (XCAR (prop))))
  73
  74 /* Return components of the composition.  */
  75 #define COMPOSITION_COMPONENTS(prop)    \
  76   (COMPOSITION_REGISTERD_P (prop)       \
  77    ? XCAR (XCDR (XCDR (prop)))          \
  78    : XCDR (XCAR (prop)))
  79
  80 /* Return modification function of the composition.  */
  81 #define COMPOSITION_MODIFICATION_FUNC(prop)     \
  82   (COMPOSITION_REGISTERD_P (prop)               \
  83    ? XCDR (XCDR (XCDR (prop)))                  \
  84    : CONSP (prop) ? XCDR (prop) : Qnil)
  85
  86 /* Return the method of composition.  */
  87 #define COMPOSITION_METHOD(prop)                                        \
  88   (COMPOSITION_REGISTERD_P (prop)                                       \
  89    ? composition_table[COMPOSITION_ID (prop)]->method                   \
  90    : (composition_temp = XCDR (XCAR (prop)),                            \
  91       (NILP (composition_temp)                                          \
  92        ? COMPOSITION_RELATIVE                                           \
  93        : (INTEGERP (composition_temp) || STRINGP (composition_temp))    \
  94        ? COMPOSITION_WITH_ALTCHARS                                      \
  95        : COMPOSITION_WITH_RULE_ALTCHARS)))
  96
  97 /* Return 1 if the composition is valid.  It is valid if length of
  98    the composition equals to (END - START).  */
  99 #define COMPOSITION_VALID_P(start, end, prop)                   \
 100   (CONSP (prop)                                                 \
 101    && (COMPOSITION_REGISTERD_P (prop)                           \
 102        ? (COMPOSITION_ID (prop) >= 0                            \
 103           && COMPOSITION_ID (prop) <= n_compositions            \
 104           && CONSP (XCDR (prop)))                               \
 105        : (composition_temp = XCAR (prop),                       \
 106           (CONSP (composition_temp)                             \
 107            && (composition_temp = XCDR (composition_temp),      \
 108                (NILP (composition_temp)                         \
 109                 || STRINGP (composition_temp)                   \
 110                 || VECTORP (composition_temp)                   \
 111                 || INTEGERP (composition_temp)                  \
 112                 || CONSP (composition_temp))))))                \
 113    && (end - start) == COMPOSITION_LENGTH (prop))
 114
 115 /* Return the Nth glyph of composition specified by CMP.  CMP is a
 116    pointer to `struct composition'.  */
 117 #define COMPOSITION_GLYPH(cmp, n)                                       \
 118   XINT (XVECTOR (XVECTOR (XHASH_TABLE (composition_hash_table)          \
 119                           ->key_and_value)                              \
 120                  ->contents[cmp->hash_index * 2])                       \
 121         ->contents[cmp->method == COMPOSITION_WITH_RULE_ALTCHARS        \
 122                   ? (n) * 2 : (n)])
 123
 124 /* Return the encoded composition rule to compose the Nth glyph of
 125    rule-base composition specified by CMP.  CMP is a pointer to
 126    `struct composition'. */
 127 #define COMPOSITION_RULE(cmp, n)                                \
 128   XINT (XVECTOR (XVECTOR (XHASH_TABLE (composition_hash_table)  \
 129                           ->key_and_value)                      \
 130                  ->contents[cmp->hash_index * 2])               \
 131         ->contents[(n) * 2 - 1])
 132
 133 /* Decode encoded composition rule RULE_CODE into GREF (global
 134    reference point code), NREF (new ref. point code).  Don't check RULE_CODE;
 135    always set GREF and NREF to valid values.  By side effect,
 136    RULE_CODE is modified.  */
 137
 138 #define COMPOSITION_DECODE_REFS(rule_code, gref, nref)                  \
 139   do {                                                                  \
 140     rule_code &= 0xFF;                                                  \
 141     gref = (rule_code) / 12;                                            \
 142     if (gref > 12) gref = 11;                                           \
 143     nref = (rule_code) % 12;                                            \
 144   } while (0)
 145
 146 /* Like COMPOSITION_DECODE_REFS (RULE_CODE, GREF, NREF), but also
 147    decode RULE_CODE into XOFF and YOFF (vertical offset).  */
 148
 149 #define COMPOSITION_DECODE_RULE(rule_code, gref, nref, xoff, yoff)      \
 150   do {                                                                  \
 151     xoff = (rule_code) >> 16;                                           \
 152     yoff = ((rule_code) >> 8) & 0xFF;                                   \
 153     COMPOSITION_DECODE_REFS (rule_code, gref, nref);                    \
 154   } while (0)
 155
 156 /* Nonzero if the global reference point GREF and new reference point NREF are
 157    valid.  */
 158 #define COMPOSITION_ENCODE_RULE_VALID(gref, nref)       \
 159   (UNSIGNED_CMP (gref, <, 12) && UNSIGNED_CMP (nref, <, 12))
 160
 161 /* Return encoded composition rule for the pair of global reference
 162    point GREF and new reference point NREF.  Arguments must be valid.  */
 163 #define COMPOSITION_ENCODE_RULE(gref, nref)             \
 164   ((gref) * 12 + (nref))
 165
 166 /* Data structure that records information about a composition
 167    currently used in some buffers or strings.
 168
 169    When a composition is assigned an ID number (by
 170    get_composition_id), this structure is allocated for the
 171    composition and linked in composition_table[ID].
 172
 173    Identical compositions appearing at different places have the same
 174    ID, and thus share the same instance of this structure.  */
 175
 176 struct composition {
 177   /* Number of glyphs of the composition components.  */
 178   int glyph_len;
 179
 180   /* Width, ascent, and descent pixels of the composition.  */
 181   short pixel_width, ascent, descent;
 182
 183   short lbearing, rbearing;
 184
 185   /* How many columns the overall glyphs occupy on the screen.  This
 186      gives an approximate value for column calculation in
 187      Fcurrent_column, and etc.  */
 188   unsigned short width;
 189
 190   /* Method of the composition.  */
 191   enum composition_method method;
 192
 193   /* Index to the composition hash table.  */
 194   ptrdiff_t hash_index;
 195
 196   /* For which font we have calculated the remaining members.  The
 197      actual type is device dependent.  */
 198   void *font;
 199
 200   /* Pointer to an array of x-offset and y-offset (by pixels) of
 201      glyphs.  This points to a sufficient memory space (sizeof (short) *
 202      glyph_len * 2) that is allocated when the composition is
 203      registered in composition_table.  X-offset and Y-offset of Nth
 204      glyph are (2N)th and (2N+1)th elements respectively.  */
 205   short *offsets;
 206 };
 207
 208 /* Table of pointers to the structure `composition' indexed by
 209    COMPOSITION-ID.  */
 210 extern struct composition **composition_table;
 211 /* Number of the currently registered compositions.  */
 212 extern ptrdiff_t n_compositions;
 213
 214 /* Mask bits for CHECK_MASK arg to update_compositions.
 215    For a change in the region FROM and TO, check compositions ... */
 216 #define CHECK_HEAD      1       /* adjacent to FROM */
 217 #define CHECK_TAIL      2       /* adjacent to TO */
 218 #define CHECK_INSIDE    4       /* between FROM and TO */
 219 #define CHECK_BORDER    (CHECK_HEAD | CHECK_TAIL)
 220 #define CHECK_ALL       (CHECK_BORDER | CHECK_INSIDE)
 221
 222 extern Lisp_Object Qcomposition;
 223 extern Lisp_Object composition_hash_table;
 224 extern ptrdiff_t get_composition_id (ptrdiff_t, ptrdiff_t, ptrdiff_t,
 225                                      Lisp_Object, Lisp_Object);
 226 extern bool find_composition (ptrdiff_t, ptrdiff_t, ptrdiff_t *, ptrdiff_t *,
 227                               Lisp_Object *, Lisp_Object);
 228 extern void update_compositions (ptrdiff_t, ptrdiff_t, int);
 229 extern void make_composition_value_copy (Lisp_Object);
 230 extern void compose_region (int, int, Lisp_Object, Lisp_Object,
 231                             Lisp_Object);
 232 extern void syms_of_composite (void);
 233 extern void compose_text (ptrdiff_t, ptrdiff_t, Lisp_Object, Lisp_Object,
 234                           Lisp_Object);
 235
 236 /* Macros for lispy glyph-string.  This is completely different from
 237    struct glyph_string.  */
 238
 239 #define LGSTRING_HEADER(lgs) AREF (lgs, 0)
 240 #define LGSTRING_SET_HEADER(lgs, header) ASET (lgs, 0, header)
 241
 242 #define LGSTRING_FONT(lgs) AREF (LGSTRING_HEADER (lgs), 0)
 243 #define LGSTRING_CHAR(lgs, i) AREF (LGSTRING_HEADER (lgs), (i) + 1)
 244 #define LGSTRING_CHAR_LEN(lgs) (ASIZE (LGSTRING_HEADER (lgs)) - 1)
 245
 246 #define LGSTRING_SET_FONT(lgs, val) ASET (LGSTRING_HEADER (lgs), 0, (val))
 247 #define LGSTRING_SET_CHAR(lgs, i, c) ASET (LGSTRING_HEADER (lgs), (i) + 1, (c))
 248
 249 #define LGSTRING_ID(lgs) AREF (lgs, 1)
 250 #define LGSTRING_SET_ID(lgs, id) ASET (lgs, 1, id)
 251
 252 #define LGSTRING_GLYPH_LEN(lgs) (ASIZE ((lgs)) - 2)
 253 #define LGSTRING_GLYPH(lgs, idx) AREF ((lgs), (idx) + 2)
 254 #define LGSTRING_SET_GLYPH(lgs, idx, val) ASET ((lgs), (idx) + 2, (val))
 255 COMPOSITE_INLINE Lisp_Object *
 256 lgstring_glyph_addr (Lisp_Object lgs, ptrdiff_t idx)
 257 {
 258   return aref_addr (lgs, idx + 2);
 259 }
 260
 261 /* Vector size of Lispy glyph.  */
 262 enum lglyph_indices
 263   {
 264     LGLYPH_IX_FROM, LGLYPH_IX_TO,  LGLYPH_IX_CHAR, LGLYPH_IX_CODE,
 265     LGLYPH_IX_WIDTH, LGLYPH_IX_LBEARING, LGLYPH_IX_RBEARING,
 266     LGLYPH_IX_ASCENT, LGLYPH_IX_DESCENT, LGLYPH_IX_ADJUSTMENT,
 267     /* Not an index.  */
 268     LGLYPH_SIZE
 269   };
 270
 271 #define LGLYPH_NEW() Fmake_vector (make_number (LGLYPH_SIZE), Qnil)
 272 #define LGLYPH_FROM(g) XINT (AREF ((g), LGLYPH_IX_FROM))
 273 #define LGLYPH_TO(g) XINT (AREF ((g), LGLYPH_IX_TO))
 274 #define LGLYPH_CHAR(g) XINT (AREF ((g), LGLYPH_IX_CHAR))
 275 #define LGLYPH_CODE(g)                                          \
 276   (NILP (AREF ((g), LGLYPH_IX_CODE))                            \
 277    ? FONT_INVALID_CODE                                          \
 278    : cons_to_unsigned (AREF (g, LGLYPH_IX_CODE), TYPE_MAXIMUM (unsigned)))
 279 #define LGLYPH_WIDTH(g) XINT (AREF ((g), LGLYPH_IX_WIDTH))
 280 #define LGLYPH_LBEARING(g) XINT (AREF ((g), LGLYPH_IX_LBEARING))
 281 #define LGLYPH_RBEARING(g) XINT (AREF ((g), LGLYPH_IX_RBEARING))
 282 #define LGLYPH_ASCENT(g) XINT (AREF ((g), LGLYPH_IX_ASCENT))
 283 #define LGLYPH_DESCENT(g) XINT (AREF ((g), LGLYPH_IX_DESCENT))
 284 #define LGLYPH_ADJUSTMENT(g) AREF ((g), LGLYPH_IX_ADJUSTMENT)
 285 #define LGLYPH_SET_FROM(g, val) ASET ((g), LGLYPH_IX_FROM, make_number (val))
 286 #define LGLYPH_SET_TO(g, val) ASET ((g), LGLYPH_IX_TO, make_number (val))
 287 #define LGLYPH_SET_CHAR(g, val) ASET ((g), LGLYPH_IX_CHAR, make_number (val))
 288 /* Callers must assure that VAL is not negative!  */
 289 #define LGLYPH_SET_CODE(g, val)                                         \
 290   ASET (g, LGLYPH_IX_CODE,                                              \
 291         val == FONT_INVALID_CODE ? Qnil : INTEGER_TO_CONS (val))
 292
 293 #define LGLYPH_SET_WIDTH(g, val) ASET ((g), LGLYPH_IX_WIDTH, make_number (val))
 294 #define LGLYPH_SET_LBEARING(g, val) ASET ((g), LGLYPH_IX_LBEARING, make_number (val))
 295 #define LGLYPH_SET_RBEARING(g, val) ASET ((g), LGLYPH_IX_RBEARING, make_number (val))
 296 #define LGLYPH_SET_ASCENT(g, val) ASET ((g), LGLYPH_IX_ASCENT, make_number (val))
 297 #define LGLYPH_SET_DESCENT(g, val) ASET ((g), LGLYPH_IX_DESCENT, make_number (val))
 298 #define LGLYPH_SET_ADJUSTMENT(g, val) ASET ((g), LGLYPH_IX_ADJUSTMENT, (val))
 299
 300 #define LGLYPH_XOFF(g) (VECTORP (LGLYPH_ADJUSTMENT (g)) \
 301                         ? XINT (AREF (LGLYPH_ADJUSTMENT (g), 0)) : 0)
 302 #define LGLYPH_YOFF(g) (VECTORP (LGLYPH_ADJUSTMENT (g)) \
 303                         ? XINT (AREF (LGLYPH_ADJUSTMENT (g), 1)) : 0)
 304 #define LGLYPH_WADJUST(g) (VECTORP (LGLYPH_ADJUSTMENT (g)) \
 305                            ? XINT (AREF (LGLYPH_ADJUSTMENT (g), 2)) : 0)
 306
 307 struct composition_it;
 308 struct face;
 309 struct font_metrics;
 310
 311 extern Lisp_Object composition_gstring_put_cache (Lisp_Object, ptrdiff_t);
 312 extern Lisp_Object composition_gstring_from_id (ptrdiff_t);
 313 extern bool composition_gstring_p (Lisp_Object);
 314 extern int composition_gstring_width (Lisp_Object, ptrdiff_t, ptrdiff_t,
 315                                       struct font_metrics *);
 316
 317 extern void composition_compute_stop_pos (struct composition_it *,
 318                                           ptrdiff_t, ptrdiff_t, ptrdiff_t,
 319                                           Lisp_Object);
 320 extern bool composition_reseat_it (struct composition_it *, ptrdiff_t,
 321                                    ptrdiff_t, ptrdiff_t, struct window *,
 322                                    struct face *, Lisp_Object);
 323 extern int composition_update_it (struct composition_it *,
 324                                   ptrdiff_t, ptrdiff_t, Lisp_Object);
 325
 326 extern ptrdiff_t composition_adjust_point (ptrdiff_t, ptrdiff_t);
 327
 328 INLINE_HEADER_END
 329
 330 #endif /* not EMACS_COMPOSITE_H */