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_PRIVATE_HH
30 #define HB_OT_LAYOUT_PRIVATE_HH
31
32 #include "hb-private.hh"
33
34 #include "hb-font-private.hh"
35 #include "hb-buffer-private.hh"
36 #include "hb-set-digest-private.hh"
37 #include "hb-open-type-private.hh"
38
39
40 /* Private API corresponding to hb-ot-layout.h: */
41
42 HB_INTERNAL hb_bool_t
43 hb_ot_layout_table_find_feature (hb_face_t *face,
44 hb_tag_t table_tag,
45 hb_tag_t feature_tag,
46 unsigned int *feature_index);
47
48
49 /*
50 * GDEF
51 */
52
53 enum hb_ot_layout_glyph_props_flags_t
54 {
55 /* The following three match LookupFlags::Ignore* numbers. */
56 HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH = 0x02u,
57 HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE = 0x04u,
58 HB_OT_LAYOUT_GLYPH_PROPS_MARK = 0x08u,
59
60 /* The following are used internally; not derived from GDEF. */
61 HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED = 0x10u,
62 HB_OT_LAYOUT_GLYPH_PROPS_LIGATED = 0x20u,
63 HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED = 0x40u,
64
65 HB_OT_LAYOUT_GLYPH_PROPS_PRESERVE = HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED |
66 HB_OT_LAYOUT_GLYPH_PROPS_LIGATED |
67 HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED
68 };
69 HB_MARK_AS_FLAG_T (hb_ot_layout_glyph_props_flags_t);
70
71
72 /*
73 * GSUB/GPOS
74 */
75
76 HB_INTERNAL hb_bool_t
77 hb_ot_layout_lookup_would_substitute_fast (hb_face_t *face,
78 unsigned int lookup_index,
79 const hb_codepoint_t *glyphs,
80 unsigned int glyphs_length,
81 hb_bool_t zero_context);
82
83
84 /* Should be called before all the substitute_lookup's are done. */
85 HB_INTERNAL void
86 hb_ot_layout_substitute_start (hb_font_t *font,
87 hb_buffer_t *buffer);
88
89
90 struct hb_ot_layout_lookup_accelerator_t;
91
92 namespace OT {
93 struct hb_ot_apply_context_t;
94 struct SubstLookup;
95 }
96
97 HB_INTERNAL void
98 hb_ot_layout_substitute_lookup (OT::hb_ot_apply_context_t *c,
99 const OT::SubstLookup &lookup,
100 const hb_ot_layout_lookup_accelerator_t &accel);
101
102
103 /* Should be called before all the position_lookup's are done. */
104 HB_INTERNAL void
105 hb_ot_layout_position_start (hb_font_t *font,
106 hb_buffer_t *buffer);
107
108 /* Should be called after all the position_lookup's are done, to fini advances. */
109 HB_INTERNAL void
110 hb_ot_layout_position_finish_advances (hb_font_t *font,
111 hb_buffer_t *buffer);
112
113 /* Should be called after hb_ot_layout_position_finish_advances, to fini offsets. */
114 HB_INTERNAL void
115 hb_ot_layout_position_finish_offsets (hb_font_t *font,
116 hb_buffer_t *buffer);
117
118
119
120 /*
121 * hb_ot_layout_t
122 */
123
124 namespace OT {
125 struct BASE;
126 struct COLR;
127 struct CPAL;
128 struct GDEF;
129 struct GSUB;
130 struct GPOS;
131 struct MATH;
132 struct fvar;
133 struct avar;
134 }
135
136 namespace AAT {
137 struct ankr;
138 struct kerx;
139 struct morx;
140 struct trak;
141 }
142
143 struct hb_ot_layout_lookup_accelerator_t
144 {
145 template <typename TLookup>
146 inline void init (const TLookup &lookup)
147 {
148 digest.init ();
149 lookup.add_coverage (&digest);
150 }
151
152 inline void fini (void)
153 {
154 }
155
156 inline bool may_have (hb_codepoint_t g) const {
157 return digest.may_have (g);
158 }
159
160 private:
161 hb_set_digest_t digest;
162 };
163
164 struct hb_ot_layout_t
165 {
166 hb_blob_t *gdef_blob;
167 hb_blob_t *gsub_blob;
168 hb_blob_t *gpos_blob;
169
170 const struct OT::GDEF *gdef;
171 const struct OT::GSUB *gsub;
172 const struct OT::GPOS *gpos;
173
174 /* TODO Move the following out of this struct. */
175 OT::hb_table_lazy_loader_t<struct OT::BASE> base;
176 OT::hb_table_lazy_loader_t<struct OT::MATH> math;
177 OT::hb_table_lazy_loader_t<struct OT::fvar> fvar;
178 OT::hb_table_lazy_loader_t<struct OT::avar> avar;
179
180 unsigned int gsub_lookup_count;
181 unsigned int gpos_lookup_count;
182
183 hb_ot_layout_lookup_accelerator_t *gsub_accels;
184 hb_ot_layout_lookup_accelerator_t *gpos_accels;
185 };
186
187
188 HB_INTERNAL hb_ot_layout_t *
189 _hb_ot_layout_create (hb_face_t *face);
190
191 HB_INTERNAL void
192 _hb_ot_layout_destroy (hb_ot_layout_t *layout);
193
194
195 #define hb_ot_layout_from_face(face) ((hb_ot_layout_t *) face->shaper_data.ot)
196
197
198 /*
199 * Buffer var routines.
200 */
201
202 /* buffer var allocations, used during the entire shaping process */
203 #define unicode_props() var2.u16[0]
204
205 /* buffer var allocations, used during the GSUB/GPOS processing */
206 #define glyph_props() var1.u16[0] /* GDEF glyph properties */
207 #define lig_props() var1.u8[2] /* GSUB/GPOS ligature tracking */
208 #define syllable() var1.u8[3] /* GSUB/GPOS shaping boundaries */
209
210
211 /* Loop over syllables. Based on foreach_cluster(). */
212 #define foreach_syllable(buffer, start, end) \
213 for (unsigned int \
214 _count = buffer->len, \
215 start = 0, end = _count ? _next_syllable (buffer, 0) : 0; \
216 start < _count; \
217 start = end, end = _next_syllable (buffer, start))
218
219 static inline unsigned int
220 _next_syllable (hb_buffer_t *buffer, unsigned int start)
221 {
222 hb_glyph_info_t *info = buffer->info;
223 unsigned int count = buffer->len;
224
225 unsigned int syllable = info[start].syllable();
226 while (++start < count && syllable == info[start].syllable())
227 ;
228
229 return start;
230 }
231
232
233 /* unicode_props */
234
235 /* Design:
236 * unicode_props() is a two-byte number. The low byte includes:
237 * - General_Category: 5 bits.
238 * - A bit each for:
239 * * Is it Default_Ignorable(); we have a modified Default_Ignorable().
240 * * Whether it's one of the three Mongolian Free Variation Selectors,
241 * CGJ, or other characters that are hidden but should not be ignored
242 * like most other Default_Ignorable()s do during matching.
243 * * One free bit right now.
244 *
245 * The high-byte has different meanings, switched by the Gen-Cat:
246 * - For Mn,Mc,Me: the modified Combining_Class.
247 * - For Cf: whether it's ZWJ, ZWNJ, or something else.
248 * - For Ws: index of which space character this is, if space fallback
249 * is needed, ie. we don't set this by default, only if asked to.
250 */
251
252 enum hb_unicode_props_flags_t {
253 UPROPS_MASK_GEN_CAT = 0x001Fu,
254 UPROPS_MASK_IGNORABLE = 0x0020u,
255 UPROPS_MASK_HIDDEN = 0x0040u, /* MONGOLIAN FREE VARIATION SELECTOR 1..3,
256 * or TAG characters */
257
258 /* If GEN_CAT=FORMAT, top byte masks: */
259 UPROPS_MASK_Cf_ZWJ = 0x0100u,
260 UPROPS_MASK_Cf_ZWNJ = 0x0200u
261 };
262 HB_MARK_AS_FLAG_T (hb_unicode_props_flags_t);
263
264 static inline void
265 _hb_glyph_info_set_unicode_props (hb_glyph_info_t *info, hb_buffer_t *buffer)
266 {
267 hb_unicode_funcs_t *unicode = buffer->unicode;
268 unsigned int u = info->codepoint;
269 unsigned int gen_cat = (unsigned int) unicode->general_category (u);
270 unsigned int props = gen_cat;
271
272 if (u >= 0x80)
273 {
274 buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_NON_ASCII;
275 if (unlikely (unicode->is_default_ignorable (u)))
276 {
277 buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_DEFAULT_IGNORABLES;
278 props |= UPROPS_MASK_IGNORABLE;
279 if (u == 0x200Cu) props |= UPROPS_MASK_Cf_ZWNJ;
280 else if (u == 0x200Du) props |= UPROPS_MASK_Cf_ZWJ;
281 /* Mongolian Free Variation Selectors need to be remembered
282 * because although we need to hide them like default-ignorables,
283 * they need to non-ignorable during shaping. This is similar to
284 * what we do for joiners in Indic-like shapers, but since the
285 * FVSes are GC=Mn, we have use a separate bit to remember them.
286 * Fixes:
287 * https://github.com/harfbuzz/harfbuzz/issues/234 */
288 else if (unlikely (hb_in_range (u, 0x180Bu, 0x180Du))) props |= UPROPS_MASK_HIDDEN;
289 /* TAG characters need similar treatment. Fixes:
290 * https://github.com/harfbuzz/harfbuzz/issues/463 */
291 else if (unlikely (hb_in_range (u, 0xE0020u, 0xE007Fu))) props |= UPROPS_MASK_HIDDEN;
292 /* COMBINING GRAPHEME JOINER should not be skipped; at least some times.
293 * https://github.com/harfbuzz/harfbuzz/issues/554 */
294 else if (unlikely (u == 0x034Fu))
295 {
296 buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_CGJ;
297 props |= UPROPS_MASK_HIDDEN;
298 }
299 }
300 else if (unlikely (HB_UNICODE_GENERAL_CATEGORY_IS_NON_ENCLOSING_MARK_OR_MODIFIER_SYMBOL (gen_cat)))
301 {
302 /* The above check is just an optimization to let in only things we need further
303 * processing on. */
304
305 /* Only Mn and Mc can have non-zero ccc:
306 * https://unicode.org/policies/stability_policy.html#Property_Value
307 * """
308 * Canonical_Combining_Class, General_Category
309 * All characters other than those with General_Category property values
310 * Spacing_Mark (Mc) and Nonspacing_Mark (Mn) have the Canonical_Combining_Class
311 * property value 0.
312 * 1.1.5+
313 * """
314 *
315 * Also, all Mn's that are Default_Ignorable, have ccc=0, hence
316 * the "else if".
317 */
318 props |= unicode->modified_combining_class (info->codepoint)<<8;
319
320 /* Recategorize emoji skin-tone modifiers as Unicode mark, so they
321 * behave correctly in non-native directionality. They originally
322 * are MODIFIER_SYMBOL. Fixes:
323 * https://github.com/harfbuzz/harfbuzz/issues/169
324 */
325 if (unlikely (hb_in_range (u, 0x1F3FBu, 0x1F3FFu)))
326 {
327 props = gen_cat = HB_UNICODE_GENERAL_CATEGORY_ENCLOSING_MARK;
328 }
329 }
330 }
331
332 info->unicode_props() = props;
333 }
334
335 static inline void
336 _hb_glyph_info_set_general_category (hb_glyph_info_t *info,
337 hb_unicode_general_category_t gen_cat)
338 {
339 /* Clears top-byte. */
340 info->unicode_props() = (unsigned int) gen_cat | (info->unicode_props() & (0xFF & ~UPROPS_MASK_GEN_CAT));
341 }
342
343 static inline hb_unicode_general_category_t
344 _hb_glyph_info_get_general_category (const hb_glyph_info_t *info)
345 {
346 return (hb_unicode_general_category_t) (info->unicode_props() & UPROPS_MASK_GEN_CAT);
347 }
348
349 static inline bool
350 _hb_glyph_info_is_unicode_mark (const hb_glyph_info_t *info)
351 {
352 return HB_UNICODE_GENERAL_CATEGORY_IS_MARK (info->unicode_props() & UPROPS_MASK_GEN_CAT);
353 }
354 static inline void
355 _hb_glyph_info_set_modified_combining_class (hb_glyph_info_t *info,
356 unsigned int modified_class)
357 {
358 if (unlikely (!_hb_glyph_info_is_unicode_mark (info)))
359 return;
360 info->unicode_props() = (modified_class<<8) | (info->unicode_props() & 0xFF);
361 }
362 static inline unsigned int
363 _hb_glyph_info_get_modified_combining_class (const hb_glyph_info_t *info)
364 {
365 return _hb_glyph_info_is_unicode_mark (info) ? info->unicode_props()>>8 : 0;
366 }
367
368
369 /* Loop over grapheme. Based on foreach_cluster(). */
370 #define foreach_grapheme(buffer, start, end) \
371 for (unsigned int \
372 _count = buffer->len, \
373 start = 0, end = _count ? _next_grapheme (buffer, 0) : 0; \
374 start < _count; \
375 start = end, end = _next_grapheme (buffer, start))
376
377 static inline unsigned int
378 _next_grapheme (hb_buffer_t *buffer, unsigned int start)
379 {
380 hb_glyph_info_t *info = buffer->info;
381 unsigned int count = buffer->len;
382
383 while (++start < count && _hb_glyph_info_is_unicode_mark (&info[start]))
384 ;
385
386 return start;
387 }
388
389
390 #define info_cc(info) (_hb_glyph_info_get_modified_combining_class (&(info)))
391
392 static inline bool
393 _hb_glyph_info_is_unicode_space (const hb_glyph_info_t *info)
394 {
395 return _hb_glyph_info_get_general_category (info) ==
396 HB_UNICODE_GENERAL_CATEGORY_SPACE_SEPARATOR;
397 }
398 static inline void
399 _hb_glyph_info_set_unicode_space_fallback_type (hb_glyph_info_t *info, hb_unicode_funcs_t::space_t s)
400 {
401 if (unlikely (!_hb_glyph_info_is_unicode_space (info)))
402 return;
403 info->unicode_props() = (((unsigned int) s)<<8) | (info->unicode_props() & 0xFF);
404 }
405 static inline hb_unicode_funcs_t::space_t
406 _hb_glyph_info_get_unicode_space_fallback_type (const hb_glyph_info_t *info)
407 {
408 return _hb_glyph_info_is_unicode_space (info) ?
409 (hb_unicode_funcs_t::space_t) (info->unicode_props()>>8) :
410 hb_unicode_funcs_t::NOT_SPACE;
411 }
412
413 static inline bool _hb_glyph_info_ligated (const hb_glyph_info_t *info);
414
415 static inline hb_bool_t
416 _hb_glyph_info_is_default_ignorable (const hb_glyph_info_t *info)
417 {
418 return (info->unicode_props() & UPROPS_MASK_IGNORABLE) &&
419 !_hb_glyph_info_ligated (info);
420 }
421 static inline hb_bool_t
422 _hb_glyph_info_is_default_ignorable_and_not_hidden (const hb_glyph_info_t *info)
423 {
424 return ((info->unicode_props() & (UPROPS_MASK_IGNORABLE|UPROPS_MASK_HIDDEN))
425 == UPROPS_MASK_IGNORABLE) &&
426 !_hb_glyph_info_ligated (info);
427 }
428 static inline void
429 _hb_glyph_info_unhide (hb_glyph_info_t *info)
430 {
431 info->unicode_props() &= ~ UPROPS_MASK_HIDDEN;
432 }
433
434 static inline bool
435 _hb_glyph_info_is_unicode_format (const hb_glyph_info_t *info)
436 {
437 return _hb_glyph_info_get_general_category (info) ==
438 HB_UNICODE_GENERAL_CATEGORY_FORMAT;
439 }
440 static inline hb_bool_t
441 _hb_glyph_info_is_zwnj (const hb_glyph_info_t *info)
442 {
443 return _hb_glyph_info_is_unicode_format (info) && (info->unicode_props() & UPROPS_MASK_Cf_ZWNJ);
444 }
445 static inline hb_bool_t
446 _hb_glyph_info_is_zwj (const hb_glyph_info_t *info)
447 {
448 return _hb_glyph_info_is_unicode_format (info) && (info->unicode_props() & UPROPS_MASK_Cf_ZWJ);
449 }
450 static inline hb_bool_t
451 _hb_glyph_info_is_joiner (const hb_glyph_info_t *info)
452 {
453 return _hb_glyph_info_is_unicode_format (info) && (info->unicode_props() & (UPROPS_MASK_Cf_ZWNJ|UPROPS_MASK_Cf_ZWJ));
454 }
455 static inline void
456 _hb_glyph_info_flip_joiners (hb_glyph_info_t *info)
457 {
458 if (!_hb_glyph_info_is_unicode_format (info))
459 return;
460 info->unicode_props() ^= UPROPS_MASK_Cf_ZWNJ | UPROPS_MASK_Cf_ZWJ;
461 }
462
463 /* lig_props: aka lig_id / lig_comp
464 *
465 * When a ligature is formed:
466 *
467 * - The ligature glyph and any marks in between all the same newly allocated
468 * lig_id,
469 * - The ligature glyph will get lig_num_comps set to the number of components
470 * - The marks get lig_comp > 0, reflecting which component of the ligature
657 {
658 HB_BUFFER_DEALLOCATE_VAR (buffer, syllable);
659 HB_BUFFER_DEALLOCATE_VAR (buffer, lig_props);
660 HB_BUFFER_DEALLOCATE_VAR (buffer, glyph_props);
661 }
662
663 static inline void
664 _hb_buffer_assert_gsubgpos_vars (hb_buffer_t *buffer)
665 {
666 HB_BUFFER_ASSERT_VAR (buffer, glyph_props);
667 HB_BUFFER_ASSERT_VAR (buffer, lig_props);
668 HB_BUFFER_ASSERT_VAR (buffer, syllable);
669 }
670
671 /* Make sure no one directly touches our props... */
672 #undef unicode_props0
673 #undef unicode_props1
674 #undef lig_props
675 #undef glyph_props
676
677 #endif /* HB_OT_LAYOUT_PRIVATE_HH */
|
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_HH
30 #define HB_OT_LAYOUT_HH
31
32 #include "hb.hh"
33
34 #include "hb-font.hh"
35 #include "hb-buffer.hh"
36 #include "hb-open-type.hh"
37 #include "hb-ot-shape.hh"
38 #include "hb-set-digest.hh"
39
40
41 struct hb_ot_shape_plan_t;
42
43
44 /*
45 * kern
46 */
47
48 HB_INTERNAL bool
49 hb_ot_layout_has_kerning (hb_face_t *face);
50
51 HB_INTERNAL bool
52 hb_ot_layout_has_machine_kerning (hb_face_t *face);
53
54 HB_INTERNAL bool
55 hb_ot_layout_has_cross_kerning (hb_face_t *face);
56
57 HB_INTERNAL void
58 hb_ot_layout_kern (const hb_ot_shape_plan_t *plan,
59 hb_font_t *font,
60 hb_buffer_t *buffer);
61
62
63 /* Private API corresponding to hb-ot-layout.h: */
64
65 HB_INTERNAL bool
66 hb_ot_layout_table_find_feature (hb_face_t *face,
67 hb_tag_t table_tag,
68 hb_tag_t feature_tag,
69 unsigned int *feature_index);
70
71
72 /*
73 * GDEF
74 */
75
76 enum hb_ot_layout_glyph_props_flags_t
77 {
78 /* The following three match LookupFlags::Ignore* numbers. */
79 HB_OT_LAYOUT_GLYPH_PROPS_BASE_GLYPH = 0x02u,
80 HB_OT_LAYOUT_GLYPH_PROPS_LIGATURE = 0x04u,
81 HB_OT_LAYOUT_GLYPH_PROPS_MARK = 0x08u,
82
83 /* The following are used internally; not derived from GDEF. */
84 HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED = 0x10u,
85 HB_OT_LAYOUT_GLYPH_PROPS_LIGATED = 0x20u,
86 HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED = 0x40u,
87
88 HB_OT_LAYOUT_GLYPH_PROPS_PRESERVE = HB_OT_LAYOUT_GLYPH_PROPS_SUBSTITUTED |
89 HB_OT_LAYOUT_GLYPH_PROPS_LIGATED |
90 HB_OT_LAYOUT_GLYPH_PROPS_MULTIPLIED
91 };
92 HB_MARK_AS_FLAG_T (hb_ot_layout_glyph_props_flags_t);
93
94
95 /*
96 * GSUB/GPOS
97 */
98
99 HB_INTERNAL bool
100 hb_ot_layout_lookup_would_substitute_fast (hb_face_t *face,
101 unsigned int lookup_index,
102 const hb_codepoint_t *glyphs,
103 unsigned int glyphs_length,
104 bool zero_context);
105
106
107 /* Should be called before all the substitute_lookup's are done. */
108 HB_INTERNAL void
109 hb_ot_layout_substitute_start (hb_font_t *font,
110 hb_buffer_t *buffer);
111
112 HB_INTERNAL void
113 hb_ot_layout_delete_glyphs_inplace (hb_buffer_t *buffer,
114 bool (*filter) (const hb_glyph_info_t *info));
115
116 namespace OT {
117 struct hb_ot_apply_context_t;
118 struct SubstLookup;
119 struct hb_ot_layout_lookup_accelerator_t;
120 }
121
122 HB_INTERNAL void
123 hb_ot_layout_substitute_lookup (OT::hb_ot_apply_context_t *c,
124 const OT::SubstLookup &lookup,
125 const OT::hb_ot_layout_lookup_accelerator_t &accel);
126
127
128 /* Should be called before all the position_lookup's are done. */
129 HB_INTERNAL void
130 hb_ot_layout_position_start (hb_font_t *font,
131 hb_buffer_t *buffer);
132
133 /* Should be called after all the position_lookup's are done, to fini advances. */
134 HB_INTERNAL void
135 hb_ot_layout_position_finish_advances (hb_font_t *font,
136 hb_buffer_t *buffer);
137
138 /* Should be called after hb_ot_layout_position_finish_advances, to fini offsets. */
139 HB_INTERNAL void
140 hb_ot_layout_position_finish_offsets (hb_font_t *font,
141 hb_buffer_t *buffer);
142
143
144 /*
145 * Buffer var routines.
146 */
147
148 /* buffer var allocations, used during the entire shaping process */
149 #define unicode_props() var2.u16[0]
150
151 /* buffer var allocations, used during the GSUB/GPOS processing */
152 #define glyph_props() var1.u16[0] /* GDEF glyph properties */
153 #define lig_props() var1.u8[2] /* GSUB/GPOS ligature tracking */
154 #define syllable() var1.u8[3] /* GSUB/GPOS shaping boundaries */
155
156
157 /* Loop over syllables. Based on foreach_cluster(). */
158 #define foreach_syllable(buffer, start, end) \
159 for (unsigned int \
160 _count = buffer->len, \
161 start = 0, end = _count ? _hb_next_syllable (buffer, 0) : 0; \
162 start < _count; \
163 start = end, end = _hb_next_syllable (buffer, start))
164
165 static inline unsigned int
166 _hb_next_syllable (hb_buffer_t *buffer, unsigned int start)
167 {
168 hb_glyph_info_t *info = buffer->info;
169 unsigned int count = buffer->len;
170
171 unsigned int syllable = info[start].syllable();
172 while (++start < count && syllable == info[start].syllable())
173 ;
174
175 return start;
176 }
177
178
179 /* unicode_props */
180
181 /* Design:
182 * unicode_props() is a two-byte number. The low byte includes:
183 * - General_Category: 5 bits.
184 * - A bit each for:
185 * * Is it Default_Ignorable(); we have a modified Default_Ignorable().
186 * * Whether it's one of the three Mongolian Free Variation Selectors,
187 * CGJ, or other characters that are hidden but should not be ignored
188 * like most other Default_Ignorable()s do during matching.
189 * * Whether it's a grapheme continuation.
190 *
191 * The high-byte has different meanings, switched by the Gen-Cat:
192 * - For Mn,Mc,Me: the modified Combining_Class.
193 * - For Cf: whether it's ZWJ, ZWNJ, or something else.
194 * - For Ws: index of which space character this is, if space fallback
195 * is needed, ie. we don't set this by default, only if asked to.
196 */
197
198 enum hb_unicode_props_flags_t {
199 UPROPS_MASK_GEN_CAT = 0x001Fu,
200 UPROPS_MASK_IGNORABLE = 0x0020u,
201 UPROPS_MASK_HIDDEN = 0x0040u, /* MONGOLIAN FREE VARIATION SELECTOR 1..3, or TAG characters */
202 UPROPS_MASK_CONTINUATION=0x0080u,
203
204 /* If GEN_CAT=FORMAT, top byte masks: */
205 UPROPS_MASK_Cf_ZWJ = 0x0100u,
206 UPROPS_MASK_Cf_ZWNJ = 0x0200u
207 };
208 HB_MARK_AS_FLAG_T (hb_unicode_props_flags_t);
209
210 static inline void
211 _hb_glyph_info_set_unicode_props (hb_glyph_info_t *info, hb_buffer_t *buffer)
212 {
213 hb_unicode_funcs_t *unicode = buffer->unicode;
214 unsigned int u = info->codepoint;
215 unsigned int gen_cat = (unsigned int) unicode->general_category (u);
216 unsigned int props = gen_cat;
217
218 if (u >= 0x80)
219 {
220 buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_NON_ASCII;
221
222 if (unlikely (unicode->is_default_ignorable (u)))
223 {
224 buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_DEFAULT_IGNORABLES;
225 props |= UPROPS_MASK_IGNORABLE;
226 if (u == 0x200Cu) props |= UPROPS_MASK_Cf_ZWNJ;
227 else if (u == 0x200Du) props |= UPROPS_MASK_Cf_ZWJ;
228 /* Mongolian Free Variation Selectors need to be remembered
229 * because although we need to hide them like default-ignorables,
230 * they need to non-ignorable during shaping. This is similar to
231 * what we do for joiners in Indic-like shapers, but since the
232 * FVSes are GC=Mn, we have use a separate bit to remember them.
233 * Fixes:
234 * https://github.com/harfbuzz/harfbuzz/issues/234 */
235 else if (unlikely (hb_in_range (u, 0x180Bu, 0x180Du))) props |= UPROPS_MASK_HIDDEN;
236 /* TAG characters need similar treatment. Fixes:
237 * https://github.com/harfbuzz/harfbuzz/issues/463 */
238 else if (unlikely (hb_in_range (u, 0xE0020u, 0xE007Fu))) props |= UPROPS_MASK_HIDDEN;
239 /* COMBINING GRAPHEME JOINER should not be skipped; at least some times.
240 * https://github.com/harfbuzz/harfbuzz/issues/554 */
241 else if (unlikely (u == 0x034Fu))
242 {
243 buffer->scratch_flags |= HB_BUFFER_SCRATCH_FLAG_HAS_CGJ;
244 props |= UPROPS_MASK_HIDDEN;
245 }
246 }
247
248 if (unlikely (HB_UNICODE_GENERAL_CATEGORY_IS_MARK (gen_cat)))
249 {
250 props |= UPROPS_MASK_CONTINUATION;
251 props |= unicode->modified_combining_class (u)<<8;
252 }
253 }
254
255 info->unicode_props() = props;
256 }
257
258 static inline void
259 _hb_glyph_info_set_general_category (hb_glyph_info_t *info,
260 hb_unicode_general_category_t gen_cat)
261 {
262 /* Clears top-byte. */
263 info->unicode_props() = (unsigned int) gen_cat | (info->unicode_props() & (0xFF & ~UPROPS_MASK_GEN_CAT));
264 }
265
266 static inline hb_unicode_general_category_t
267 _hb_glyph_info_get_general_category (const hb_glyph_info_t *info)
268 {
269 return (hb_unicode_general_category_t) (info->unicode_props() & UPROPS_MASK_GEN_CAT);
270 }
271
272 static inline bool
273 _hb_glyph_info_is_unicode_mark (const hb_glyph_info_t *info)
274 {
275 return HB_UNICODE_GENERAL_CATEGORY_IS_MARK (info->unicode_props() & UPROPS_MASK_GEN_CAT);
276 }
277 static inline void
278 _hb_glyph_info_set_modified_combining_class (hb_glyph_info_t *info,
279 unsigned int modified_class)
280 {
281 if (unlikely (!_hb_glyph_info_is_unicode_mark (info)))
282 return;
283 info->unicode_props() = (modified_class<<8) | (info->unicode_props() & 0xFF);
284 }
285 static inline unsigned int
286 _hb_glyph_info_get_modified_combining_class (const hb_glyph_info_t *info)
287 {
288 return _hb_glyph_info_is_unicode_mark (info) ? info->unicode_props()>>8 : 0;
289 }
290 #define info_cc(info) (_hb_glyph_info_get_modified_combining_class (&(info)))
291
292 static inline bool
293 _hb_glyph_info_is_unicode_space (const hb_glyph_info_t *info)
294 {
295 return _hb_glyph_info_get_general_category (info) ==
296 HB_UNICODE_GENERAL_CATEGORY_SPACE_SEPARATOR;
297 }
298 static inline void
299 _hb_glyph_info_set_unicode_space_fallback_type (hb_glyph_info_t *info, hb_unicode_funcs_t::space_t s)
300 {
301 if (unlikely (!_hb_glyph_info_is_unicode_space (info)))
302 return;
303 info->unicode_props() = (((unsigned int) s)<<8) | (info->unicode_props() & 0xFF);
304 }
305 static inline hb_unicode_funcs_t::space_t
306 _hb_glyph_info_get_unicode_space_fallback_type (const hb_glyph_info_t *info)
307 {
308 return _hb_glyph_info_is_unicode_space (info) ?
309 (hb_unicode_funcs_t::space_t) (info->unicode_props()>>8) :
310 hb_unicode_funcs_t::NOT_SPACE;
311 }
312
313 static inline bool _hb_glyph_info_ligated (const hb_glyph_info_t *info);
314
315 static inline bool
316 _hb_glyph_info_is_default_ignorable (const hb_glyph_info_t *info)
317 {
318 return (info->unicode_props() & UPROPS_MASK_IGNORABLE) &&
319 !_hb_glyph_info_ligated (info);
320 }
321 static inline bool
322 _hb_glyph_info_is_default_ignorable_and_not_hidden (const hb_glyph_info_t *info)
323 {
324 return ((info->unicode_props() & (UPROPS_MASK_IGNORABLE|UPROPS_MASK_HIDDEN))
325 == UPROPS_MASK_IGNORABLE) &&
326 !_hb_glyph_info_ligated (info);
327 }
328 static inline void
329 _hb_glyph_info_unhide (hb_glyph_info_t *info)
330 {
331 info->unicode_props() &= ~ UPROPS_MASK_HIDDEN;
332 }
333
334 static inline void
335 _hb_glyph_info_set_continuation (hb_glyph_info_t *info)
336 {
337 info->unicode_props() |= UPROPS_MASK_CONTINUATION;
338 }
339 static inline void
340 _hb_glyph_info_reset_continuation (hb_glyph_info_t *info)
341 {
342 info->unicode_props() &= ~ UPROPS_MASK_CONTINUATION;
343 }
344 static inline bool
345 _hb_glyph_info_is_continuation (const hb_glyph_info_t *info)
346 {
347 return info->unicode_props() & UPROPS_MASK_CONTINUATION;
348 }
349 /* Loop over grapheme. Based on foreach_cluster(). */
350 #define foreach_grapheme(buffer, start, end) \
351 for (unsigned int \
352 _count = buffer->len, \
353 start = 0, end = _count ? _hb_next_grapheme (buffer, 0) : 0; \
354 start < _count; \
355 start = end, end = _hb_next_grapheme (buffer, start))
356
357 static inline unsigned int
358 _hb_next_grapheme (hb_buffer_t *buffer, unsigned int start)
359 {
360 hb_glyph_info_t *info = buffer->info;
361 unsigned int count = buffer->len;
362
363 while (++start < count && _hb_glyph_info_is_continuation (&info[start]))
364 ;
365
366 return start;
367 }
368
369 static inline bool
370 _hb_glyph_info_is_unicode_format (const hb_glyph_info_t *info)
371 {
372 return _hb_glyph_info_get_general_category (info) ==
373 HB_UNICODE_GENERAL_CATEGORY_FORMAT;
374 }
375 static inline bool
376 _hb_glyph_info_is_zwnj (const hb_glyph_info_t *info)
377 {
378 return _hb_glyph_info_is_unicode_format (info) && (info->unicode_props() & UPROPS_MASK_Cf_ZWNJ);
379 }
380 static inline bool
381 _hb_glyph_info_is_zwj (const hb_glyph_info_t *info)
382 {
383 return _hb_glyph_info_is_unicode_format (info) && (info->unicode_props() & UPROPS_MASK_Cf_ZWJ);
384 }
385 static inline bool
386 _hb_glyph_info_is_joiner (const hb_glyph_info_t *info)
387 {
388 return _hb_glyph_info_is_unicode_format (info) && (info->unicode_props() & (UPROPS_MASK_Cf_ZWNJ|UPROPS_MASK_Cf_ZWJ));
389 }
390 static inline void
391 _hb_glyph_info_flip_joiners (hb_glyph_info_t *info)
392 {
393 if (!_hb_glyph_info_is_unicode_format (info))
394 return;
395 info->unicode_props() ^= UPROPS_MASK_Cf_ZWNJ | UPROPS_MASK_Cf_ZWJ;
396 }
397
398 /* lig_props: aka lig_id / lig_comp
399 *
400 * When a ligature is formed:
401 *
402 * - The ligature glyph and any marks in between all the same newly allocated
403 * lig_id,
404 * - The ligature glyph will get lig_num_comps set to the number of components
405 * - The marks get lig_comp > 0, reflecting which component of the ligature
592 {
593 HB_BUFFER_DEALLOCATE_VAR (buffer, syllable);
594 HB_BUFFER_DEALLOCATE_VAR (buffer, lig_props);
595 HB_BUFFER_DEALLOCATE_VAR (buffer, glyph_props);
596 }
597
598 static inline void
599 _hb_buffer_assert_gsubgpos_vars (hb_buffer_t *buffer)
600 {
601 HB_BUFFER_ASSERT_VAR (buffer, glyph_props);
602 HB_BUFFER_ASSERT_VAR (buffer, lig_props);
603 HB_BUFFER_ASSERT_VAR (buffer, syllable);
604 }
605
606 /* Make sure no one directly touches our props... */
607 #undef unicode_props0
608 #undef unicode_props1
609 #undef lig_props
610 #undef glyph_props
611
612 #endif /* HB_OT_LAYOUT_HH */
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