gfx/harfbuzz/src/hb-unicode.hh

   1 /*
   2  * Copyright © 2009  Red Hat, Inc.
   3  * Copyright © 2011  Codethink Limited
   4  * Copyright © 2010,2011,2012  Google, Inc.
   5  *
   6  *  This is part of HarfBuzz, a text shaping library.
   7  *
   8  * Permission is hereby granted, without written agreement and without
   9  * license or royalty fees, to use, copy, modify, and distribute this
  10  * software and its documentation for any purpose, provided that the
  11  * above copyright notice and the following two paragraphs appear in
  12  * all copies of this software.
  13  *
  14  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  15  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  16  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  17  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  18  * DAMAGE.
  19  *
  20  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  21  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  22  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  23  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  24  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  25  *
  26  * Red Hat Author(s): Behdad Esfahbod
  27  * Codethink Author(s): Ryan Lortie
  28  * Google Author(s): Behdad Esfahbod
  29  */
  30
  31 #ifndef HB_UNICODE_HH
  32 #define HB_UNICODE_HH
  33
  34 #include "hb.hh"
  35
  36
  37 extern HB_INTERNAL const uint8_t _hb_modified_combining_class[256];
  38
  39 /*
  40  * hb_unicode_funcs_t
  41  */
  42
  43 #define HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS \
  44   HB_UNICODE_FUNC_IMPLEMENT (combining_class) \
  45   HB_IF_NOT_DEPRECATED (HB_UNICODE_FUNC_IMPLEMENT (eastasian_width)) \
  46   HB_UNICODE_FUNC_IMPLEMENT (general_category) \
  47   HB_UNICODE_FUNC_IMPLEMENT (mirroring) \
  48   HB_UNICODE_FUNC_IMPLEMENT (script) \
  49   HB_UNICODE_FUNC_IMPLEMENT (compose) \
  50   HB_UNICODE_FUNC_IMPLEMENT (decompose) \
  51   HB_IF_NOT_DEPRECATED (HB_UNICODE_FUNC_IMPLEMENT (decompose_compatibility)) \
  52   /* ^--- Add new callbacks here */
  53
  54 /* Simple callbacks are those taking a hb_codepoint_t and returning a hb_codepoint_t */
  55 #define HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS_SIMPLE \
  56   HB_UNICODE_FUNC_IMPLEMENT (hb_unicode_combining_class_t, combining_class) \
  57   HB_IF_NOT_DEPRECATED (HB_UNICODE_FUNC_IMPLEMENT (unsigned int, eastasian_width)) \
  58   HB_UNICODE_FUNC_IMPLEMENT (hb_unicode_general_category_t, general_category) \
  59   HB_UNICODE_FUNC_IMPLEMENT (hb_codepoint_t, mirroring) \
  60   HB_UNICODE_FUNC_IMPLEMENT (hb_script_t, script) \
  61   /* ^--- Add new simple callbacks here */
  62
  63 struct hb_unicode_funcs_t
  64 {
  65   hb_object_header_t header;
  66
  67   hb_unicode_funcs_t *parent;
  68
  69 #define HB_UNICODE_FUNC_IMPLEMENT(return_type, name) \
  70   return_type name (hb_codepoint_t unicode) { return func.name (this, unicode, user_data.name); }
  71 HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS_SIMPLE
  72 #undef HB_UNICODE_FUNC_IMPLEMENT
  73
  74   hb_bool_t compose (hb_codepoint_t a, hb_codepoint_t b,
  75                      hb_codepoint_t *ab)
  76   {
  77     *ab = 0;
  78     if (unlikely (!a || !b)) return false;
  79     return func.compose (this, a, b, ab, user_data.compose);
  80   }
  81
  82   hb_bool_t decompose (hb_codepoint_t ab,
  83                        hb_codepoint_t *a, hb_codepoint_t *b)
  84   {
  85     *a = ab; *b = 0;
  86     return func.decompose (this, ab, a, b, user_data.decompose);
  87   }
  88
  89   unsigned int decompose_compatibility (hb_codepoint_t  u,
  90                                         hb_codepoint_t *decomposed)
  91   {
  92 #ifdef HB_DISABLE_DEPRECATED
  93     unsigned int ret  = 0;
  94 #else
  95     unsigned int ret = func.decompose_compatibility (this, u, decomposed, user_data.decompose_compatibility);
  96 #endif
  97     if (ret == 1 && u == decomposed[0]) {
  98       decomposed[0] = 0;
  99       return 0;
 100     }
 101     decomposed[ret] = 0;
 102     return ret;
 103   }
 104
 105   unsigned int
 106   modified_combining_class (hb_codepoint_t u)
 107   {
 108     /* XXX This hack belongs to the USE shaper (for Tai Tham):
 109      * Reorder SAKOT to ensure it comes after any tone marks. */
 110     if (unlikely (u == 0x1A60u)) return 254;
 111
 112     /* XXX This hack belongs to the Tibetan shaper:
 113      * Reorder PADMA to ensure it comes after any vowel marks. */
 114     if (unlikely (u == 0x0FC6u)) return 254;
 115     /* Reorder TSA -PHRU to reorder before U+0F74 */
 116     if (unlikely (u == 0x0F39u)) return 127;
 117
 118     return _hb_modified_combining_class[combining_class (u)];
 119   }
 120
 121   static hb_bool_t
 122   is_variation_selector (hb_codepoint_t unicode)
 123   {
 124     /* U+180B..180D, U+180F MONGOLIAN FREE VARIATION SELECTORs are handled in the
 125      * Arabic shaper.  No need to match them here. */
 126     return unlikely (hb_in_ranges<hb_codepoint_t> (unicode,
 127                                                    0xFE00u, 0xFE0Fu, /* VARIATION SELECTOR-1..16 */
 128                                                    0xE0100u, 0xE01EFu));  /* VARIATION SELECTOR-17..256 */
 129   }
 130
 131   /* Default_Ignorable codepoints:
 132    *
 133    * Note: While U+115F, U+1160, U+3164 and U+FFA0 are Default_Ignorable,
 134    * we do NOT want to hide them, as the way Uniscribe has implemented them
 135    * is with regular spacing glyphs, and that's the way fonts are made to work.
 136    * As such, we make exceptions for those four.
 137    * Also ignoring U+1BCA0..1BCA3. https://github.com/harfbuzz/harfbuzz/issues/503
 138    *
 139    * Unicode 14.0:
 140    * $ grep '; Default_Ignorable_Code_Point ' DerivedCoreProperties.txt | sed 's/;.*#/#/'
 141    * 00AD          # Cf       SOFT HYPHEN
 142    * 034F          # Mn       COMBINING GRAPHEME JOINER
 143    * 061C          # Cf       ARABIC LETTER MARK
 144    * 115F..1160    # Lo   [2] HANGUL CHOSEONG FILLER..HANGUL JUNGSEONG FILLER
 145    * 17B4..17B5    # Mn   [2] KHMER VOWEL INHERENT AQ..KHMER VOWEL INHERENT AA
 146    * 180B..180D    # Mn   [3] MONGOLIAN FREE VARIATION SELECTOR ONE..MONGOLIAN FREE VARIATION SELECTOR THREE
 147    * 180E          # Cf       MONGOLIAN VOWEL SEPARATOR
 148    * 180F          # Mn       MONGOLIAN FREE VARIATION SELECTOR FOUR
 149    * 200B..200F    # Cf   [5] ZERO WIDTH SPACE..RIGHT-TO-LEFT MARK
 150    * 202A..202E    # Cf   [5] LEFT-TO-RIGHT EMBEDDING..RIGHT-TO-LEFT OVERRIDE
 151    * 2060..2064    # Cf   [5] WORD JOINER..INVISIBLE PLUS
 152    * 2065          # Cn       <reserved-2065>
 153    * 2066..206F    # Cf  [10] LEFT-TO-RIGHT ISOLATE..NOMINAL DIGIT SHAPES
 154    * 3164          # Lo       HANGUL FILLER
 155    * FE00..FE0F    # Mn  [16] VARIATION SELECTOR-1..VARIATION SELECTOR-16
 156    * FEFF          # Cf       ZERO WIDTH NO-BREAK SPACE
 157    * FFA0          # Lo       HALFWIDTH HANGUL FILLER
 158    * FFF0..FFF8    # Cn   [9] <reserved-FFF0>..<reserved-FFF8>
 159    * 1BCA0..1BCA3  # Cf   [4] SHORTHAND FORMAT LETTER OVERLAP..SHORTHAND FORMAT UP STEP
 160    * 1D173..1D17A  # Cf   [8] MUSICAL SYMBOL BEGIN BEAM..MUSICAL SYMBOL END PHRASE
 161    * E0000         # Cn       <reserved-E0000>
 162    * E0001         # Cf       LANGUAGE TAG
 163    * E0002..E001F  # Cn  [30] <reserved-E0002>..<reserved-E001F>
 164    * E0020..E007F  # Cf  [96] TAG SPACE..CANCEL TAG
 165    * E0080..E00FF  # Cn [128] <reserved-E0080>..<reserved-E00FF>
 166    * E0100..E01EF  # Mn [240] VARIATION SELECTOR-17..VARIATION SELECTOR-256
 167    * E01F0..E0FFF  # Cn [3600] <reserved-E01F0>..<reserved-E0FFF>
 168    */
 169   static hb_bool_t
 170   is_default_ignorable (hb_codepoint_t ch)
 171   {
 172     hb_codepoint_t plane = ch >> 16;
 173     if (likely (plane == 0))
 174     {
 175       /* BMP */
 176       hb_codepoint_t page = ch >> 8;
 177       switch (page) {
 178         case 0x00: return unlikely (ch == 0x00ADu);
 179         case 0x03: return unlikely (ch == 0x034Fu);
 180         case 0x06: return unlikely (ch == 0x061Cu);
 181         case 0x17: return hb_in_range<hb_codepoint_t> (ch, 0x17B4u, 0x17B5u);
 182         case 0x18: return hb_in_range<hb_codepoint_t> (ch, 0x180Bu, 0x180Eu);
 183         case 0x20: return hb_in_ranges<hb_codepoint_t> (ch, 0x200Bu, 0x200Fu,
 184                                             0x202Au, 0x202Eu,
 185                                             0x2060u, 0x206Fu);
 186         case 0xFE: return hb_in_range<hb_codepoint_t> (ch, 0xFE00u, 0xFE0Fu) || ch == 0xFEFFu;
 187         case 0xFF: return hb_in_range<hb_codepoint_t> (ch, 0xFFF0u, 0xFFF8u);
 188         default: return false;
 189       }
 190     }
 191     else
 192     {
 193       /* Other planes */
 194       switch (plane) {
 195         case 0x01: return hb_in_range<hb_codepoint_t> (ch, 0x1D173u, 0x1D17Au);
 196         case 0x0E: return hb_in_range<hb_codepoint_t> (ch, 0xE0000u, 0xE0FFFu);
 197         default: return false;
 198       }
 199     }
 200   }
 201
 202   /* Space estimates based on:
 203    * https://unicode.org/charts/PDF/U2000.pdf
 204    * https://docs.microsoft.com/en-us/typography/develop/character-design-standards/whitespace
 205    */
 206   enum space_t {
 207     NOT_SPACE = 0,
 208     SPACE_EM   = 1,
 209     SPACE_EM_2 = 2,
 210     SPACE_EM_3 = 3,
 211     SPACE_EM_4 = 4,
 212     SPACE_EM_5 = 5,
 213     SPACE_EM_6 = 6,
 214     SPACE_EM_16 = 16,
 215     SPACE_4_EM_18,      /* 4/18th of an EM! */
 216     SPACE,
 217     SPACE_FIGURE,
 218     SPACE_PUNCTUATION,
 219     SPACE_NARROW,
 220   };
 221   static space_t
 222   space_fallback_type (hb_codepoint_t u)
 223   {
 224     switch (u)
 225     {
 226       /* All GC=Zs chars that can use a fallback. */
 227       default:      return NOT_SPACE;   /* U+1680 OGHAM SPACE MARK */
 228       case 0x0020u: return SPACE;       /* U+0020 SPACE */
 229       case 0x00A0u: return SPACE;       /* U+00A0 NO-BREAK SPACE */
 230       case 0x2000u: return SPACE_EM_2;  /* U+2000 EN QUAD */
 231       case 0x2001u: return SPACE_EM;    /* U+2001 EM QUAD */
 232       case 0x2002u: return SPACE_EM_2;  /* U+2002 EN SPACE */
 233       case 0x2003u: return SPACE_EM;    /* U+2003 EM SPACE */
 234       case 0x2004u: return SPACE_EM_3;  /* U+2004 THREE-PER-EM SPACE */
 235       case 0x2005u: return SPACE_EM_4;  /* U+2005 FOUR-PER-EM SPACE */
 236       case 0x2006u: return SPACE_EM_6;  /* U+2006 SIX-PER-EM SPACE */
 237       case 0x2007u: return SPACE_FIGURE;        /* U+2007 FIGURE SPACE */
 238       case 0x2008u: return SPACE_PUNCTUATION;   /* U+2008 PUNCTUATION SPACE */
 239       case 0x2009u: return SPACE_EM_5;          /* U+2009 THIN SPACE */
 240       case 0x200Au: return SPACE_EM_16;         /* U+200A HAIR SPACE */
 241       case 0x202Fu: return SPACE_NARROW;        /* U+202F NARROW NO-BREAK SPACE */
 242       case 0x205Fu: return SPACE_4_EM_18;       /* U+205F MEDIUM MATHEMATICAL SPACE */
 243       case 0x3000u: return SPACE_EM;            /* U+3000 IDEOGRAPHIC SPACE */
 244     }
 245   }
 246
 247   struct {
 248 #define HB_UNICODE_FUNC_IMPLEMENT(name) hb_unicode_##name##_func_t name;
 249     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
 250 #undef HB_UNICODE_FUNC_IMPLEMENT
 251   } func;
 252
 253   struct {
 254 #define HB_UNICODE_FUNC_IMPLEMENT(name) void *name;
 255     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
 256 #undef HB_UNICODE_FUNC_IMPLEMENT
 257   } user_data;
 258
 259   struct {
 260 #define HB_UNICODE_FUNC_IMPLEMENT(name) hb_destroy_func_t name;
 261     HB_UNICODE_FUNCS_IMPLEMENT_CALLBACKS
 262 #undef HB_UNICODE_FUNC_IMPLEMENT
 263   } destroy;
 264 };
 265 DECLARE_NULL_INSTANCE (hb_unicode_funcs_t);
 266
 267
 268 /*
 269  * Modified combining marks
 270  */
 271
 272 /* Hebrew
 273  *
 274  * We permute the "fixed-position" classes 10-26 into the order
 275  * described in the SBL Hebrew manual:
 276  *
 277  * https://www.sbl-site.org/Fonts/SBLHebrewUserManual1.5x.pdf
 278  *
 279  * (as recommended by:
 280  *  https://forum.fontlab.com/archive-old-microsoft-volt-group/vista-and-diacritic-ordering/msg22823/)
 281  *
 282  * More details here:
 283  * https://bugzilla.mozilla.org/show_bug.cgi?id=662055
 284  */
 285 #define HB_MODIFIED_COMBINING_CLASS_CCC10 22 /* sheva */
 286 #define HB_MODIFIED_COMBINING_CLASS_CCC11 15 /* hataf segol */
 287 #define HB_MODIFIED_COMBINING_CLASS_CCC12 16 /* hataf patah */
 288 #define HB_MODIFIED_COMBINING_CLASS_CCC13 17 /* hataf qamats */
 289 #define HB_MODIFIED_COMBINING_CLASS_CCC14 23 /* hiriq */
 290 #define HB_MODIFIED_COMBINING_CLASS_CCC15 18 /* tsere */
 291 #define HB_MODIFIED_COMBINING_CLASS_CCC16 19 /* segol */
 292 #define HB_MODIFIED_COMBINING_CLASS_CCC17 20 /* patah */
 293 #define HB_MODIFIED_COMBINING_CLASS_CCC18 21 /* qamats & qamats qatan */
 294 #define HB_MODIFIED_COMBINING_CLASS_CCC19 14 /* holam & holam haser for vav*/
 295 #define HB_MODIFIED_COMBINING_CLASS_CCC20 24 /* qubuts */
 296 #define HB_MODIFIED_COMBINING_CLASS_CCC21 12 /* dagesh */
 297 #define HB_MODIFIED_COMBINING_CLASS_CCC22 25 /* meteg */
 298 #define HB_MODIFIED_COMBINING_CLASS_CCC23 13 /* rafe */
 299 #define HB_MODIFIED_COMBINING_CLASS_CCC24 10 /* shin dot */
 300 #define HB_MODIFIED_COMBINING_CLASS_CCC25 11 /* sin dot */
 301 #define HB_MODIFIED_COMBINING_CLASS_CCC26 26 /* point varika */
 302
 303 /*
 304  * Arabic
 305  *
 306  * Modify to move Shadda (ccc=33) before other marks.  See:
 307  * https://unicode.org/faq/normalization.html#8
 308  * https://unicode.org/faq/normalization.html#9
 309  */
 310 #define HB_MODIFIED_COMBINING_CLASS_CCC27 28 /* fathatan */
 311 #define HB_MODIFIED_COMBINING_CLASS_CCC28 29 /* dammatan */
 312 #define HB_MODIFIED_COMBINING_CLASS_CCC29 30 /* kasratan */
 313 #define HB_MODIFIED_COMBINING_CLASS_CCC30 31 /* fatha */
 314 #define HB_MODIFIED_COMBINING_CLASS_CCC31 32 /* damma */
 315 #define HB_MODIFIED_COMBINING_CLASS_CCC32 33 /* kasra */
 316 #define HB_MODIFIED_COMBINING_CLASS_CCC33 27 /* shadda */
 317 #define HB_MODIFIED_COMBINING_CLASS_CCC34 34 /* sukun */
 318 #define HB_MODIFIED_COMBINING_CLASS_CCC35 35 /* superscript alef */
 319
 320 /* Syriac */
 321 #define HB_MODIFIED_COMBINING_CLASS_CCC36 36 /* superscript alaph */
 322
 323 /* Telugu
 324  *
 325  * Modify Telugu length marks (ccc=84, ccc=91).
 326  * These are the only matras in the main Indic scripts range that have
 327  * a non-zero ccc.  That makes them reorder with the Halant (ccc=9).
 328  * Assign 4 and 5, which are otherwise unassigned.
 329  */
 330 #define HB_MODIFIED_COMBINING_CLASS_CCC84 4 /* length mark */
 331 #define HB_MODIFIED_COMBINING_CLASS_CCC91 5 /* ai length mark */
 332
 333 /* Thai
 334  *
 335  * Modify U+0E38 and U+0E39 (ccc=103) to be reordered before U+0E3A (ccc=9).
 336  * Assign 3, which is unassigned otherwise.
 337  * Uniscribe does this reordering too.
 338  */
 339 #define HB_MODIFIED_COMBINING_CLASS_CCC103 3 /* sara u / sara uu */
 340 #define HB_MODIFIED_COMBINING_CLASS_CCC107 107 /* mai * */
 341
 342 /* Lao */
 343 #define HB_MODIFIED_COMBINING_CLASS_CCC118 118 /* sign u / sign uu */
 344 #define HB_MODIFIED_COMBINING_CLASS_CCC122 122 /* mai * */
 345
 346 /* Tibetan
 347  *
 348  * In case of multiple vowel-signs, use u first (but after achung)
 349  * this allows Dzongkha multi-vowel shortcuts to render correctly
 350  */
 351 #define HB_MODIFIED_COMBINING_CLASS_CCC129 129 /* sign aa */
 352 #define HB_MODIFIED_COMBINING_CLASS_CCC130 132 /* sign i */
 353 #define HB_MODIFIED_COMBINING_CLASS_CCC132 131 /* sign u */
 354
 355 /* Misc */
 356
 357 #define HB_UNICODE_GENERAL_CATEGORY_IS_MARK(gen_cat) \
 358         (FLAG_UNSAFE (gen_cat) & \
 359          (FLAG (HB_UNICODE_GENERAL_CATEGORY_SPACING_MARK) | \
 360           FLAG (HB_UNICODE_GENERAL_CATEGORY_ENCLOSING_MARK) | \
 361           FLAG (HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK)))
 362
 363 #define HB_UNICODE_GENERAL_CATEGORY_IS_LETTER(gen_cat) \
 364         (FLAG_UNSAFE (gen_cat) & \
 365          (FLAG (HB_UNICODE_GENERAL_CATEGORY_LOWERCASE_LETTER) | \
 366           FLAG (HB_UNICODE_GENERAL_CATEGORY_MODIFIER_LETTER) | \
 367           FLAG (HB_UNICODE_GENERAL_CATEGORY_OTHER_LETTER) | \
 368           FLAG (HB_UNICODE_GENERAL_CATEGORY_TITLECASE_LETTER) | \
 369           FLAG (HB_UNICODE_GENERAL_CATEGORY_UPPERCASE_LETTER)))
 370
 371 /*
 372  * Ranges, used for bsearch tables.
 373  */
 374
 375 struct hb_unicode_range_t
 376 {
 377   static int
 378   cmp (const void *_key, const void *_item)
 379   {
 380     hb_codepoint_t cp = *((hb_codepoint_t *) _key);
 381     const hb_unicode_range_t *range = (hb_unicode_range_t *) _item;
 382
 383     if (cp < range->start)
 384       return -1;
 385     else if (cp <= range->end)
 386       return 0;
 387     else
 388       return +1;
 389   }
 390
 391   hb_codepoint_t start;
 392   hb_codepoint_t end;
 393 };
 394
 395 /*
 396  * Emoji.
 397  */
 398
 399 HB_INTERNAL bool
 400 _hb_unicode_is_emoji_Extended_Pictographic (hb_codepoint_t cp);
 401
 402
 403 extern "C" HB_INTERNAL hb_unicode_funcs_t *hb_ucd_get_unicode_funcs ();
 404
 405
 406 #endif /* HB_UNICODE_HH */