hb-ot-layout-gdef-table.hh revision ae9877dea6a1aed3566d9b87a75ede84259deaca 
1/*
2 * Copyright © 2007,2008,2009  Red Hat, Inc.
3 * Copyright © 2010,2011  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
38/*
39 * Attachment List Table
40 */
41
42typedef ArrayOf<USHORT> AttachPoint;	/* Array of contour point indices--in
43					 * increasing numerical order */
44
45struct AttachList
46{
47  inline unsigned int get_attach_points (hb_codepoint_t glyph_id,
48					 unsigned int start_offset,
49					 unsigned int *point_count /* IN/OUT */,
50					 unsigned int *point_array /* OUT */) const
51  {
52    unsigned int index = (this+coverage) (glyph_id);
53    if (index == NOT_COVERED)
54    {
55      if (point_count)
56	*point_count = 0;
57      return 0;
58    }
59
60    const AttachPoint &points = this+attachPoint[index];
61
62    if (point_count) {
63      const USHORT *array = points.sub_array (start_offset, point_count);
64      unsigned int count = *point_count;
65      for (unsigned int i = 0; i < count; i++)
66	point_array[i] = array[i];
67    }
68
69    return points.len;
70  }
71
72  inline bool sanitize (hb_sanitize_context_t *c) {
73    TRACE_SANITIZE ();
74    return coverage.sanitize (c, this)
75	&& attachPoint.sanitize (c, this);
76  }
77
78  private:
79  OffsetTo<Coverage>
80		coverage;		/* Offset to Coverage table -- from
81					 * beginning of AttachList table */
82  OffsetArrayOf<AttachPoint>
83		attachPoint;		/* Array of AttachPoint tables
84					 * in Coverage Index order */
85  public:
86  DEFINE_SIZE_ARRAY (4, attachPoint);
87};
88
89/*
90 * Ligature Caret Table
91 */
92
93struct CaretValueFormat1
94{
95  friend struct CaretValue;
96
97  private:
98  inline hb_position_t get_caret_value (hb_font_t *font, hb_direction_t direction, hb_codepoint_t glyph_id HB_UNUSED) const
99  {
100    return HB_DIRECTION_IS_HORIZONTAL (direction) ? font->em_scale_x (coordinate) : font->em_scale_y (coordinate);
101  }
102
103  inline bool sanitize (hb_sanitize_context_t *c) {
104    TRACE_SANITIZE ();
105    return c->check_struct (this);
106  }
107
108  private:
109  USHORT	caretValueFormat;	/* Format identifier--format = 1 */
110  SHORT		coordinate;		/* X or Y value, in design units */
111  public:
112  DEFINE_SIZE_STATIC (4);
113};
114
115struct CaretValueFormat2
116{
117  friend struct CaretValue;
118
119  private:
120  inline hb_position_t get_caret_value (hb_font_t *font, hb_direction_t direction, hb_codepoint_t glyph_id) const
121  {
122    hb_position_t x, y;
123    if (hb_font_get_glyph_contour_point_for_origin (font, glyph_id, caretValuePoint, direction, &x, &y))
124      return HB_DIRECTION_IS_HORIZONTAL (direction) ? x : y;
125    else
126      return 0;
127  }
128
129  inline bool sanitize (hb_sanitize_context_t *c) {
130    TRACE_SANITIZE ();
131    return c->check_struct (this);
132  }
133
134  private:
135  USHORT	caretValueFormat;	/* Format identifier--format = 2 */
136  USHORT	caretValuePoint;	/* Contour point index on glyph */
137  public:
138  DEFINE_SIZE_STATIC (4);
139};
140
141struct CaretValueFormat3
142{
143  friend struct CaretValue;
144
145  inline hb_position_t get_caret_value (hb_font_t *font, hb_direction_t direction, hb_codepoint_t glyph_id HB_UNUSED) const
146  {
147    return HB_DIRECTION_IS_HORIZONTAL (direction) ?
148           font->em_scale_x (coordinate) + (this+deviceTable).get_x_delta (font) :
149           font->em_scale_y (coordinate) + (this+deviceTable).get_y_delta (font);
150  }
151
152  inline bool sanitize (hb_sanitize_context_t *c) {
153    TRACE_SANITIZE ();
154    return c->check_struct (this)
155	&& deviceTable.sanitize (c, this);
156  }
157
158  private:
159  USHORT	caretValueFormat;	/* Format identifier--format = 3 */
160  SHORT		coordinate;		/* X or Y value, in design units */
161  OffsetTo<Device>
162		deviceTable;		/* Offset to Device table for X or Y
163					 * value--from beginning of CaretValue
164					 * table */
165  public:
166  DEFINE_SIZE_STATIC (6);
167};
168
169struct CaretValue
170{
171  inline hb_position_t get_caret_value (hb_font_t *font, hb_direction_t direction, hb_codepoint_t glyph_id) const
172  {
173    switch (u.format) {
174    case 1: return u.format1.get_caret_value (font, direction, glyph_id);
175    case 2: return u.format2.get_caret_value (font, direction, glyph_id);
176    case 3: return u.format3.get_caret_value (font, direction, glyph_id);
177    default:return 0;
178    }
179  }
180
181  inline bool sanitize (hb_sanitize_context_t *c) {
182    TRACE_SANITIZE ();
183    if (!u.format.sanitize (c)) return false;
184    switch (u.format) {
185    case 1: return u.format1.sanitize (c);
186    case 2: return u.format2.sanitize (c);
187    case 3: return u.format3.sanitize (c);
188    default:return true;
189    }
190  }
191
192  private:
193  union {
194  USHORT		format;		/* Format identifier */
195  CaretValueFormat1	format1;
196  CaretValueFormat2	format2;
197  CaretValueFormat3	format3;
198  } u;
199  public:
200  DEFINE_SIZE_UNION (2, format);
201};
202
203struct LigGlyph
204{
205  inline unsigned int get_lig_carets (hb_font_t *font,
206				      hb_direction_t direction,
207				      hb_codepoint_t glyph_id,
208				      unsigned int start_offset,
209				      unsigned int *caret_count /* IN/OUT */,
210				      hb_position_t *caret_array /* OUT */) const
211  {
212    if (caret_count) {
213      const OffsetTo<CaretValue> *array = carets.sub_array (start_offset, caret_count);
214      unsigned int count = *caret_count;
215      for (unsigned int i = 0; i < count; i++)
216	caret_array[i] = (this+array[i]).get_caret_value (font, direction, glyph_id);
217    }
218
219    return carets.len;
220  }
221
222  inline bool sanitize (hb_sanitize_context_t *c) {
223    TRACE_SANITIZE ();
224    return carets.sanitize (c, this);
225  }
226
227  private:
228  OffsetArrayOf<CaretValue>
229		carets;			/* Offset array of CaretValue tables
230					 * --from beginning of LigGlyph table
231					 * --in increasing coordinate order */
232  public:
233  DEFINE_SIZE_ARRAY (2, carets);
234};
235
236struct LigCaretList
237{
238  inline unsigned int get_lig_carets (hb_font_t *font,
239				      hb_direction_t direction,
240				      hb_codepoint_t glyph_id,
241				      unsigned int start_offset,
242				      unsigned int *caret_count /* IN/OUT */,
243				      hb_position_t *caret_array /* OUT */) const
244  {
245    unsigned int index = (this+coverage) (glyph_id);
246    if (index == NOT_COVERED)
247    {
248      if (caret_count)
249	*caret_count = 0;
250      return 0;
251    }
252    const LigGlyph &lig_glyph = this+ligGlyph[index];
253    return lig_glyph.get_lig_carets (font, direction, glyph_id, start_offset, caret_count, caret_array);
254  }
255
256  inline bool sanitize (hb_sanitize_context_t *c) {
257    TRACE_SANITIZE ();
258    return coverage.sanitize (c, this)
259	&& ligGlyph.sanitize (c, this);
260  }
261
262  private:
263  OffsetTo<Coverage>
264		coverage;		/* Offset to Coverage table--from
265					 * beginning of LigCaretList table */
266  OffsetArrayOf<LigGlyph>
267		ligGlyph;		/* Array of LigGlyph tables
268					 * in Coverage Index order */
269  public:
270  DEFINE_SIZE_ARRAY (4, ligGlyph);
271};
272
273
274struct MarkGlyphSetsFormat1
275{
276  inline bool covers (unsigned int set_index, hb_codepoint_t glyph_id) const
277  { return (this+coverage[set_index]).get_coverage (glyph_id) != NOT_COVERED; }
278
279  inline bool sanitize (hb_sanitize_context_t *c) {
280    TRACE_SANITIZE ();
281    return coverage.sanitize (c, this);
282  }
283
284  private:
285  USHORT	format;			/* Format identifier--format = 1 */
286  LongOffsetArrayOf<Coverage>
287		coverage;		/* Array of long offsets to mark set
288					 * coverage tables */
289  public:
290  DEFINE_SIZE_ARRAY (4, coverage);
291};
292
293struct MarkGlyphSets
294{
295  inline bool covers (unsigned int set_index, hb_codepoint_t glyph_id) const
296  {
297    switch (u.format) {
298    case 1: return u.format1.covers (set_index, glyph_id);
299    default:return false;
300    }
301  }
302
303  inline bool sanitize (hb_sanitize_context_t *c) {
304    TRACE_SANITIZE ();
305    if (!u.format.sanitize (c)) return false;
306    switch (u.format) {
307    case 1: return u.format1.sanitize (c);
308    default:return true;
309    }
310  }
311
312  private:
313  union {
314  USHORT		format;		/* Format identifier */
315  MarkGlyphSetsFormat1	format1;
316  } u;
317  public:
318  DEFINE_SIZE_UNION (2, format);
319};
320
321
322/*
323 * GDEF -- The Glyph Definition Table
324 */
325
326struct GDEF
327{
328  static const hb_tag_t Tag	= HB_OT_TAG_GDEF;
329
330  enum {
331    UnclassifiedGlyph	= 0,
332    BaseGlyph		= 1,
333    LigatureGlyph	= 2,
334    MarkGlyph		= 3,
335    ComponentGlyph	= 4
336  };
337
338  inline bool has_glyph_classes (void) const { return glyphClassDef != 0; }
339  inline unsigned int get_glyph_class (hb_codepoint_t glyph) const
340  { return (this+glyphClassDef).get_class (glyph); }
341
342  inline bool has_mark_attachment_types (void) const { return markAttachClassDef != 0; }
343  inline unsigned int get_mark_attachment_type (hb_codepoint_t glyph) const
344  { return (this+markAttachClassDef).get_class (glyph); }
345
346  inline bool has_attach_points (void) const { return attachList != 0; }
347  inline unsigned int get_attach_points (hb_codepoint_t glyph_id,
348					 unsigned int start_offset,
349					 unsigned int *point_count /* IN/OUT */,
350					 unsigned int *point_array /* OUT */) const
351  { return (this+attachList).get_attach_points (glyph_id, start_offset, point_count, point_array); }
352
353  inline bool has_lig_carets (void) const { return ligCaretList != 0; }
354  inline unsigned int get_lig_carets (hb_font_t *font,
355				      hb_direction_t direction,
356				      hb_codepoint_t glyph_id,
357				      unsigned int start_offset,
358				      unsigned int *caret_count /* IN/OUT */,
359				      hb_position_t *caret_array /* OUT */) const
360  { return (this+ligCaretList).get_lig_carets (font, direction, glyph_id, start_offset, caret_count, caret_array); }
361
362  inline bool has_mark_sets (void) const { return version.to_int () >= 0x00010002 && markGlyphSetsDef[0] != 0; }
363  inline bool mark_set_covers (unsigned int set_index, hb_codepoint_t glyph_id) const
364  { return version.to_int () >= 0x00010002 && (this+markGlyphSetsDef[0]).covers (set_index, glyph_id); }
365
366  inline bool sanitize (hb_sanitize_context_t *c) {
367    TRACE_SANITIZE ();
368    return version.sanitize (c) && likely (version.major == 1)
369	&& glyphClassDef.sanitize (c, this)
370	&& attachList.sanitize (c, this)
371	&& ligCaretList.sanitize (c, this)
372	&& markAttachClassDef.sanitize (c, this)
373	&& (version.to_int () < 0x00010002 || markGlyphSetsDef[0].sanitize (c, this));
374  }
375
376
377  /* glyph_props is a 16-bit integer where the lower 8-bit have bits representing
378   * glyph class and other bits, and high 8-bit gthe mark attachment type (if any).
379   * Not to be confused with lookup_props which is very similar. */
380  inline unsigned int get_glyph_props (hb_codepoint_t glyph) const
381  {
382    unsigned int klass = get_glyph_class (glyph);
383
384    switch (klass) {
385    default:
386    case UnclassifiedGlyph:	return HB_OT_LAYOUT_GLYPH_CLASS_UNCLASSIFIED;
387    case BaseGlyph:		return HB_OT_LAYOUT_GLYPH_CLASS_BASE_GLYPH;
388    case LigatureGlyph:		return HB_OT_LAYOUT_GLYPH_CLASS_LIGATURE;
389    case ComponentGlyph:	return HB_OT_LAYOUT_GLYPH_CLASS_COMPONENT;
390    case MarkGlyph:
391	  klass = get_mark_attachment_type (glyph);
392	  return HB_OT_LAYOUT_GLYPH_CLASS_MARK | (klass << 8);
393    }
394  }
395
396
397  private:
398  FixedVersion	version;		/* Version of the GDEF table--currently
399					 * 0x00010002 */
400  OffsetTo<ClassDef>
401		glyphClassDef;		/* Offset to class definition table
402					 * for glyph type--from beginning of
403					 * GDEF header (may be Null) */
404  OffsetTo<AttachList>
405		attachList;		/* Offset to list of glyphs with
406					 * attachment points--from beginning
407					 * of GDEF header (may be Null) */
408  OffsetTo<LigCaretList>
409		ligCaretList;		/* Offset to list of positioning points
410					 * for ligature carets--from beginning
411					 * of GDEF header (may be Null) */
412  OffsetTo<ClassDef>
413		markAttachClassDef;	/* Offset to class definition table for
414					 * mark attachment type--from beginning
415					 * of GDEF header (may be Null) */
416  OffsetTo<MarkGlyphSets>
417		markGlyphSetsDef[VAR];	/* Offset to the table of mark set
418					 * definitions--from beginning of GDEF
419					 * header (may be NULL).  Introduced
420					 * in version 00010002. */
421  public:
422  DEFINE_SIZE_ARRAY (12, markGlyphSetsDef);
423};
424
425
426
427#endif /* HB_OT_LAYOUT_GDEF_TABLE_HH */
428