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