third_party/harfbuzz-ng/src/hb-ot-layout-gdef-table.hh

   1 /*
   2  * Copyright © 2007,2008,2009  Red Hat, Inc.
   3  * Copyright © 2010,2011,2012  Google, Inc.
   4  *
   5  *  This is part of HarfBuzz, a text shaping library.
   6  *
   7  * Permission is hereby granted, without written agreement and without
   8  * license or royalty fees, to use, copy, modify, and distribute this
   9  * software and its documentation for any purpose, provided that the
  10  * above copyright notice and the following two paragraphs appear in
  11  * all copies of this software.
  12  *
  13  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
  14  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
  15  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
  16  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
  17  * DAMAGE.
  18  *
  19  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
  20  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
  21  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
  22  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
  23  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
  24  *
  25  * Red Hat Author(s): Behdad Esfahbod
  26  * Google Author(s): Behdad Esfahbod
  27  */
  28
  29 #ifndef HB_OT_LAYOUT_GDEF_TABLE_HH
  30 #define HB_OT_LAYOUT_GDEF_TABLE_HH
  31
  32 #include "hb-ot-layout-common-private.hh"
  33
  34 #include "hb-font-private.hh"
  35
  36
  37 namespace OT {
  38
  39
  40 /*
  41  * Attachment List Table
  42  */
  43
  44 typedef ArrayOf<USHORT> AttachPoint;    /* Array of contour point indices--in
  45                                          * increasing numerical order */
  46
  47 struct AttachList
  48 {
  49   inline unsigned int get_attach_points (hb_codepoint_t glyph_id,
  50                                          unsigned int start_offset,
  51                                          unsigned int *point_count /* IN/OUT */,
  52                                          unsigned int *point_array /* OUT */) const
  53   {
  54     unsigned int index = (this+coverage).get_coverage (glyph_id);
  55     if (index == NOT_COVERED)
  56     {
  57       if (point_count)
  58         *point_count = 0;
  59       return 0;
  60     }
  61
  62     const AttachPoint &points = this+attachPoint[index];
  63
  64     if (point_count) {
  65       const USHORT *array = points.sub_array (start_offset, point_count);
  66       unsigned int count = *point_count;
  67       for (unsigned int i = 0; i < count; i++)
  68         point_array[i] = array[i];
  69     }
  70
  71     return points.len;
  72   }
  73
  74   inline bool sanitize (hb_sanitize_context_t *c) const
  75   {
  76     TRACE_SANITIZE (this);
  77     return TRACE_RETURN (coverage.sanitize (c, this) && attachPoint.sanitize (c, this));
  78   }
  79
  80   protected:
  81   OffsetTo<Coverage>
  82                 coverage;               /* Offset to Coverage table -- from
  83                                          * beginning of AttachList table */
  84   OffsetArrayOf<AttachPoint>
  85                 attachPoint;            /* Array of AttachPoint tables
  86                                          * in Coverage Index order */
  87   public:
  88   DEFINE_SIZE_ARRAY (4, attachPoint);
  89 };
  90
  91 /*
  92  * Ligature Caret Table
  93  */
  94
  95 struct CaretValueFormat1
  96 {
  97   friend struct CaretValue;
  98
  99   private:
 100   inline hb_position_t get_caret_value (hb_font_t *font, hb_direction_t direction, hb_codepoint_t glyph_id HB_UNUSED) const
 101   {
 102     return HB_DIRECTION_IS_HORIZONTAL (direction) ? font->em_scale_x (coordinate) : font->em_scale_y (coordinate);
 103   }
 104
 105   inline bool sanitize (hb_sanitize_context_t *c) const
 106   {
 107     TRACE_SANITIZE (this);
 108     return TRACE_RETURN (c->check_struct (this));
 109   }
 110
 111   protected:
 112   USHORT        caretValueFormat;       /* Format identifier--format = 1 */
 113   SHORT         coordinate;             /* X or Y value, in design units */
 114   public:
 115   DEFINE_SIZE_STATIC (4);
 116 };
 117
 118 struct CaretValueFormat2
 119 {
 120   friend struct CaretValue;
 121
 122   private:
 123   inline hb_position_t get_caret_value (hb_font_t *font, hb_direction_t direction, hb_codepoint_t glyph_id) const
 124   {
 125     hb_position_t x, y;
 126     if (font->get_glyph_contour_point_for_origin (glyph_id, caretValuePoint, direction, &x, &y))
 127       return HB_DIRECTION_IS_HORIZONTAL (direction) ? x : y;
 128     else
 129       return 0;
 130   }
 131
 132   inline bool sanitize (hb_sanitize_context_t *c) const
 133   {
 134     TRACE_SANITIZE (this);
 135     return TRACE_RETURN (c->check_struct (this));
 136   }
 137
 138   protected:
 139   USHORT        caretValueFormat;       /* Format identifier--format = 2 */
 140   USHORT        caretValuePoint;        /* Contour point index on glyph */
 141   public:
 142   DEFINE_SIZE_STATIC (4);
 143 };
 144
 145 struct CaretValueFormat3
 146 {
 147   friend struct CaretValue;
 148
 149   inline hb_position_t get_caret_value (hb_font_t *font, hb_direction_t direction, hb_codepoint_t glyph_id HB_UNUSED) const
 150   {
 151     return HB_DIRECTION_IS_HORIZONTAL (direction) ?
 152            font->em_scale_x (coordinate) + (this+deviceTable).get_x_delta (font) :
 153            font->em_scale_y (coordinate) + (this+deviceTable).get_y_delta (font);
 154   }
 155
 156   inline bool sanitize (hb_sanitize_context_t *c) const
 157   {
 158     TRACE_SANITIZE (this);
 159     return TRACE_RETURN (c->check_struct (this) && deviceTable.sanitize (c, this));
 160   }
 161
 162   protected:
 163   USHORT        caretValueFormat;       /* Format identifier--format = 3 */
 164   SHORT         coordinate;             /* X or Y value, in design units */
 165   OffsetTo<Device>
 166                 deviceTable;            /* Offset to Device table for X or Y
 167                                          * value--from beginning of CaretValue
 168                                          * table */
 169   public:
 170   DEFINE_SIZE_STATIC (6);
 171 };
 172
 173 struct CaretValue
 174 {
 175   inline hb_position_t get_caret_value (hb_font_t *font, hb_direction_t direction, hb_codepoint_t glyph_id) const
 176   {
 177     switch (u.format) {
 178     case 1: return u.format1.get_caret_value (font, direction, glyph_id);
 179     case 2: return u.format2.get_caret_value (font, direction, glyph_id);
 180     case 3: return u.format3.get_caret_value (font, direction, glyph_id);
 181     default:return 0;
 182     }
 183   }
 184
 185   inline bool sanitize (hb_sanitize_context_t *c) const
 186   {
 187     TRACE_SANITIZE (this);
 188     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
 189     switch (u.format) {
 190     case 1: return TRACE_RETURN (u.format1.sanitize (c));
 191     case 2: return TRACE_RETURN (u.format2.sanitize (c));
 192     case 3: return TRACE_RETURN (u.format3.sanitize (c));
 193     default:return TRACE_RETURN (true);
 194     }
 195   }
 196
 197   protected:
 198   union {
 199   USHORT                format;         /* Format identifier */
 200   CaretValueFormat1     format1;
 201   CaretValueFormat2     format2;
 202   CaretValueFormat3     format3;
 203   } u;
 204   public:
 205   DEFINE_SIZE_UNION (2, format);
 206 };
 207
 208 struct LigGlyph
 209 {
 210   inline unsigned int get_lig_carets (hb_font_t *font,
 211                                       hb_direction_t direction,
 212                                       hb_codepoint_t glyph_id,
 213                                       unsigned int start_offset,
 214                                       unsigned int *caret_count /* IN/OUT */,
 215                                       hb_position_t *caret_array /* OUT */) const
 216   {
 217     if (caret_count) {
 218       const OffsetTo<CaretValue> *array = carets.sub_array (start_offset, caret_count);
 219       unsigned int count = *caret_count;
 220       for (unsigned int i = 0; i < count; i++)
 221         caret_array[i] = (this+array[i]).get_caret_value (font, direction, glyph_id);
 222     }
 223
 224     return carets.len;
 225   }
 226
 227   inline bool sanitize (hb_sanitize_context_t *c) const
 228   {
 229     TRACE_SANITIZE (this);
 230     return TRACE_RETURN (carets.sanitize (c, this));
 231   }
 232
 233   protected:
 234   OffsetArrayOf<CaretValue>
 235                 carets;                 /* Offset array of CaretValue tables
 236                                          * --from beginning of LigGlyph table
 237                                          * --in increasing coordinate order */
 238   public:
 239   DEFINE_SIZE_ARRAY (2, carets);
 240 };
 241
 242 struct LigCaretList
 243 {
 244   inline unsigned int get_lig_carets (hb_font_t *font,
 245                                       hb_direction_t direction,
 246                                       hb_codepoint_t glyph_id,
 247                                       unsigned int start_offset,
 248                                       unsigned int *caret_count /* IN/OUT */,
 249                                       hb_position_t *caret_array /* OUT */) const
 250   {
 251     unsigned int index = (this+coverage).get_coverage (glyph_id);
 252     if (index == NOT_COVERED)
 253     {
 254       if (caret_count)
 255         *caret_count = 0;
 256       return 0;
 257     }
 258     const LigGlyph &lig_glyph = this+ligGlyph[index];
 259     return lig_glyph.get_lig_carets (font, direction, glyph_id, start_offset, caret_count, caret_array);
 260   }
 261
 262   inline bool sanitize (hb_sanitize_context_t *c) const
 263   {
 264     TRACE_SANITIZE (this);
 265     return TRACE_RETURN (coverage.sanitize (c, this) && ligGlyph.sanitize (c, this));
 266   }
 267
 268   protected:
 269   OffsetTo<Coverage>
 270                 coverage;               /* Offset to Coverage table--from
 271                                          * beginning of LigCaretList table */
 272   OffsetArrayOf<LigGlyph>
 273                 ligGlyph;               /* Array of LigGlyph tables
 274                                          * in Coverage Index order */
 275   public:
 276   DEFINE_SIZE_ARRAY (4, ligGlyph);
 277 };
 278
 279
 280 struct MarkGlyphSetsFormat1
 281 {
 282   inline bool covers (unsigned int set_index, hb_codepoint_t glyph_id) const
 283   { return (this+coverage[set_index]).get_coverage (glyph_id) != NOT_COVERED; }
 284
 285   inline bool sanitize (hb_sanitize_context_t *c) const
 286   {
 287     TRACE_SANITIZE (this);
 288     return TRACE_RETURN (coverage.sanitize (c, this));
 289   }
 290
 291   protected:
 292   USHORT        format;                 /* Format identifier--format = 1 */
 293   ArrayOf<OffsetTo<Coverage, ULONG> >
 294                 coverage;               /* Array of long offsets to mark set
 295                                          * coverage tables */
 296   public:
 297   DEFINE_SIZE_ARRAY (4, coverage);
 298 };
 299
 300 struct MarkGlyphSets
 301 {
 302   inline bool covers (unsigned int set_index, hb_codepoint_t glyph_id) const
 303   {
 304     switch (u.format) {
 305     case 1: return u.format1.covers (set_index, glyph_id);
 306     default:return false;
 307     }
 308   }
 309
 310   inline bool sanitize (hb_sanitize_context_t *c) const
 311   {
 312     TRACE_SANITIZE (this);
 313     if (!u.format.sanitize (c)) return TRACE_RETURN (false);
 314     switch (u.format) {
 315     case 1: return TRACE_RETURN (u.format1.sanitize (c));
 316     default:return TRACE_RETURN (true);
 317     }
 318   }
 319
 320   protected:
 321   union {
 322   USHORT                format;         /* Format identifier */
 323   MarkGlyphSetsFormat1  format1;
 324   } u;
 325   public:
 326   DEFINE_SIZE_UNION (2, format);
 327 };
 328
 329
 330 /*
 331  * GDEF -- The Glyph Definition Table
 332  */
 333
 334 struct GDEF
 335 {
 336   static const hb_tag_t tableTag        = HB_OT_TAG_GDEF;
 337
 338   enum GlyphClasses {
 339     UnclassifiedGlyph   = 0,
 340     BaseGlyph           = 1,
 341     LigatureGlyph       = 2,
 342     MarkGlyph           = 3,
 343     ComponentGlyph      = 4
 344   };
 345
 346   inline bool has_glyph_classes (void) const { return glyphClassDef != 0; }
 347   inline unsigned int get_glyph_class (hb_codepoint_t glyph) const
 348   { return (this+glyphClassDef).get_class (glyph); }
 349   inline void get_glyphs_in_class (unsigned int klass, hb_set_t *glyphs) const
 350   { (this+glyphClassDef).add_class (glyphs, klass); }
 351
 352   inline bool has_mark_attachment_types (void) const { return markAttachClassDef != 0; }
 353   inline unsigned int get_mark_attachment_type (hb_codepoint_t glyph) const
 354   { return (this+markAttachClassDef).get_class (glyph); }
 355
 356   inline bool has_attach_points (void) const { return attachList != 0; }
 357   inline unsigned int get_attach_points (hb_codepoint_t glyph_id,
 358                                          unsigned int start_offset,
 359                                          unsigned int *point_count /* IN/OUT */,
 360                                          unsigned int *point_array /* OUT */) const
 361   { return (this+attachList).get_attach_points (glyph_id, start_offset, point_count, point_array); }
 362
 363   inline bool has_lig_carets (void) const { return ligCaretList != 0; }
 364   inline unsigned int get_lig_carets (hb_font_t *font,
 365                                       hb_direction_t direction,
 366                                       hb_codepoint_t glyph_id,
 367                                       unsigned int start_offset,
 368                                       unsigned int *caret_count /* IN/OUT */,
 369                                       hb_position_t *caret_array /* OUT */) const
 370   { return (this+ligCaretList).get_lig_carets (font, direction, glyph_id, start_offset, caret_count, caret_array); }
 371
 372   inline bool has_mark_sets (void) const { return version.to_int () >= 0x00010002u && markGlyphSetsDef[0] != 0; }
 373   inline bool mark_set_covers (unsigned int set_index, hb_codepoint_t glyph_id) const
 374   { return version.to_int () >= 0x00010002u && (this+markGlyphSetsDef[0]).covers (set_index, glyph_id); }
 375
 376   inline bool sanitize (hb_sanitize_context_t *c) const
 377   {
 378     TRACE_SANITIZE (this);
 379     return TRACE_RETURN (version.sanitize (c) &&
 380                          likely (version.major == 1) &&
 381                          glyphClassDef.sanitize (c, this) &&
 382                          attachList.sanitize (c, this) &&
 383                          ligCaretList.sanitize (c, this) &&
 384                          markAttachClassDef.sanitize (c, this) &&
 385                          (version.to_int () < 0x00010002u || markGlyphSetsDef[0].sanitize (c, this)));
 386   }
 387
 388
 389   /* glyph_props is a 16-bit integer where the lower 8-bit have bits representing
 390    * glyph class and other bits, and high 8-bit gthe mark attachment type (if any).
 391    * Not to be confused with lookup_props which is very similar. */
 392   inline unsigned int get_glyph_props (hb_codepoint_t glyph) const
 393   {
 394     unsigned int klass = get_glyph_class (glyph);
 395
 396     ASSERT_STATIC ((unsigned int) HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH == (unsigned int) LookupFlag::IgnoreBaseGlyphs);
 397     ASSERT_STATIC ((unsigned int) HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE == (unsigned int) LookupFlag::IgnoreLigatures);
 398     ASSERT_STATIC ((unsigned int) HB_OT_LAYOUT_GLYPH_PROPS_MARK == (unsigned int) LookupFlag::IgnoreMarks);
 399
 400     switch (klass) {
 401     default:                    return 0;
 402     case BaseGlyph:             return HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH;
 403     case LigatureGlyph:         return HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE;
 404     case MarkGlyph:
 405           klass = get_mark_attachment_type (glyph);
 406           return HB_OT_LAYOUT_GLYPH_PROPS_MARK | (klass << 8);
 407     }
 408   }
 409
 410
 411   protected:
 412   FixedVersion  version;                /* Version of the GDEF table--currently
 413                                          * 0x00010002u */
 414   OffsetTo<ClassDef>
 415                 glyphClassDef;          /* Offset to class definition table
 416                                          * for glyph type--from beginning of
 417                                          * GDEF header (may be Null) */
 418   OffsetTo<AttachList>
 419                 attachList;             /* Offset to list of glyphs with
 420                                          * attachment points--from beginning
 421                                          * of GDEF header (may be Null) */
 422   OffsetTo<LigCaretList>
 423                 ligCaretList;           /* Offset to list of positioning points
 424                                          * for ligature carets--from beginning
 425                                          * of GDEF header (may be Null) */
 426   OffsetTo<ClassDef>
 427                 markAttachClassDef;     /* Offset to class definition table for
 428                                          * mark attachment type--from beginning
 429                                          * of GDEF header (may be Null) */
 430   OffsetTo<MarkGlyphSets>
 431                 markGlyphSetsDef[VAR];  /* Offset to the table of mark set
 432                                          * definitions--from beginning of GDEF
 433                                          * header (may be NULL).  Introduced
 434                                          * in version 00010002. */
 435   public:
 436   DEFINE_SIZE_ARRAY (12, markGlyphSetsDef);
 437 };
 438
 439
 440 } /* namespace OT */
 441
 442
 443 #endif /* HB_OT_LAYOUT_GDEF_TABLE_HH */