xref: /aosp_15_r20/external/harfbuzz_ng/src/hb-ot-var-hvar-table.hh (revision 2d1272b857b1f7575e6e246373e1cb218663db8a)
1 /*
2  * Copyright © 2017  Google, Inc.
3  *
4  *  This is part of HarfBuzz, a text shaping library.
5  *
6  * Permission is hereby granted, without written agreement and without
7  * license or royalty fees, to use, copy, modify, and distribute this
8  * software and its documentation for any purpose, provided that the
9  * above copyright notice and the following two paragraphs appear in
10  * all copies of this software.
11  *
12  * IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
13  * DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
14  * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
15  * IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
16  * DAMAGE.
17  *
18  * THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
19  * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20  * FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
21  * ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
22  * PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
23  *
24  * Google Author(s): Behdad Esfahbod
25  */
26 
27 #ifndef HB_OT_VAR_HVAR_TABLE_HH
28 #define HB_OT_VAR_HVAR_TABLE_HH
29 
30 #include "hb-ot-layout-common.hh"
31 #include "hb-ot-var-common.hh"
32 
33 namespace OT {
34 
35 
36 struct index_map_subset_plan_t
37 {
38   enum index_map_index_t {
39     ADV_INDEX,
40     LSB_INDEX,	/* dual as TSB */
41     RSB_INDEX,	/* dual as BSB */
42     VORG_INDEX
43   };
44 
initOT::index_map_subset_plan_t45   void init (const DeltaSetIndexMap  &index_map,
46 	     hb_inc_bimap_t	     &outer_map,
47 	     hb_vector_t<hb_set_t *> &inner_sets,
48 	     const hb_subset_plan_t  *plan,
49 	     bool bypass_empty = true)
50   {
51     map_count = 0;
52     outer_bit_count = 0;
53     inner_bit_count = 1;
54     max_inners.init ();
55     output_map.init ();
56 
57     if (bypass_empty && !index_map.get_map_count ()) return;
58 
59     unsigned int	last_val = (unsigned int)-1;
60     hb_codepoint_t	last_gid = HB_CODEPOINT_INVALID;
61 
62     outer_bit_count = (index_map.get_width () * 8) - index_map.get_inner_bit_count ();
63     max_inners.resize (inner_sets.length);
64     for (unsigned i = 0; i < inner_sets.length; i++) max_inners[i] = 0;
65 
66     /* Search backwards for a map value different from the last map value */
67     auto &new_to_old_gid_list = plan->new_to_old_gid_list;
68     unsigned count = new_to_old_gid_list.length;
69     for (unsigned j = count; j; j--)
70     {
71       hb_codepoint_t gid = new_to_old_gid_list.arrayZ[j - 1].first;
72       hb_codepoint_t old_gid = new_to_old_gid_list.arrayZ[j - 1].second;
73 
74       unsigned int v = index_map.map (old_gid);
75       if (last_gid == HB_CODEPOINT_INVALID)
76       {
77 	last_val = v;
78 	last_gid = gid;
79 	continue;
80       }
81       if (v != last_val)
82 	break;
83 
84       last_gid = gid;
85     }
86 
87     if (unlikely (last_gid == (hb_codepoint_t)-1)) return;
88     map_count = last_gid + 1;
89     for (auto _ : plan->new_to_old_gid_list)
90     {
91       hb_codepoint_t gid = _.first;
92       if (gid >= map_count) break;
93 
94       hb_codepoint_t old_gid = _.second;
95       unsigned int v = index_map.map (old_gid);
96       unsigned int outer = v >> 16;
97       unsigned int inner = v & 0xFFFF;
98       outer_map.add (outer);
99       if (inner > max_inners[outer]) max_inners[outer] = inner;
100       if (outer >= inner_sets.length) return;
101       inner_sets[outer]->add (inner);
102     }
103   }
104 
finiOT::index_map_subset_plan_t105   void fini ()
106   {
107     max_inners.fini ();
108     output_map.fini ();
109   }
110 
remapOT::index_map_subset_plan_t111   void remap (const DeltaSetIndexMap *input_map,
112 	      const hb_inc_bimap_t &outer_map,
113 	      const hb_vector_t<hb_inc_bimap_t> &inner_maps,
114 	      const hb_subset_plan_t *plan)
115   {
116     for (unsigned int i = 0; i < max_inners.length; i++)
117     {
118       if (inner_maps[i].get_population () == 0) continue;
119       unsigned int bit_count = (max_inners[i]==0)? 1: hb_bit_storage (inner_maps[i][max_inners[i]]);
120       if (bit_count > inner_bit_count) inner_bit_count = bit_count;
121     }
122 
123     if (unlikely (!output_map.resize (map_count))) return;
124     for (const auto &_ : plan->new_to_old_gid_list)
125     {
126       hb_codepoint_t new_gid = _.first;
127       hb_codepoint_t old_gid = _.second;
128 
129       if (unlikely (new_gid >= map_count)) break;
130 
131       uint32_t v = input_map->map (old_gid);
132       unsigned int outer = v >> 16;
133       output_map.arrayZ[new_gid] = (outer_map[outer] << 16) | (inner_maps[outer][v & 0xFFFF]);
134     }
135   }
136 
remap_after_instantiationOT::index_map_subset_plan_t137   bool remap_after_instantiation (const hb_subset_plan_t *plan,
138                                   const hb_map_t& varidx_map)
139   {
140     /* recalculate bit_count after remapping */
141     outer_bit_count = 1;
142     inner_bit_count = 1;
143 
144     for (const auto &_ : plan->new_to_old_gid_list)
145     {
146       hb_codepoint_t new_gid = _.first;
147       if (unlikely (new_gid >= map_count)) break;
148 
149       uint32_t v = output_map.arrayZ[new_gid];
150       uint32_t *new_varidx;
151       if (!varidx_map.has (v, &new_varidx))
152         return false;
153 
154       output_map.arrayZ[new_gid] = *new_varidx;
155 
156       unsigned outer = (*new_varidx) >> 16;
157       unsigned bit_count = (outer == 0) ? 1 : hb_bit_storage (outer);
158       outer_bit_count = hb_max (bit_count, outer_bit_count);
159 
160       unsigned inner = (*new_varidx) & 0xFFFF;
161       bit_count = (inner == 0) ? 1 : hb_bit_storage (inner);
162       inner_bit_count = hb_max (bit_count, inner_bit_count);
163     }
164     return true;
165   }
166 
get_inner_bit_countOT::index_map_subset_plan_t167   unsigned int get_inner_bit_count () const { return inner_bit_count; }
get_widthOT::index_map_subset_plan_t168   unsigned int get_width ()           const { return ((outer_bit_count + inner_bit_count + 7) / 8); }
get_map_countOT::index_map_subset_plan_t169   unsigned int get_map_count ()       const { return map_count; }
170 
get_sizeOT::index_map_subset_plan_t171   unsigned int get_size () const
172   { return (map_count? (DeltaSetIndexMap::min_size + get_width () * map_count): 0); }
173 
is_identityOT::index_map_subset_plan_t174   bool is_identity () const { return get_output_map ().length == 0; }
get_output_mapOT::index_map_subset_plan_t175   hb_array_t<const uint32_t> get_output_map () const { return output_map.as_array (); }
176 
177   protected:
178   unsigned int map_count;
179   hb_vector_t<unsigned int> max_inners;
180   unsigned int outer_bit_count;
181   unsigned int inner_bit_count;
182   hb_vector_t<uint32_t> output_map;
183 };
184 
185 struct hvarvvar_subset_plan_t
186 {
hvarvvar_subset_plan_tOT::hvarvvar_subset_plan_t187   hvarvvar_subset_plan_t() : inner_maps (), index_map_plans () {}
~hvarvvar_subset_plan_tOT::hvarvvar_subset_plan_t188   ~hvarvvar_subset_plan_t() { fini (); }
189 
initOT::hvarvvar_subset_plan_t190   void init (const hb_array_t<const DeltaSetIndexMap *> &index_maps,
191 	     const ItemVariationStore &_var_store,
192 	     const hb_subset_plan_t *plan)
193   {
194     index_map_plans.resize (index_maps.length);
195 
196     var_store = &_var_store;
197     inner_sets.resize (var_store->get_sub_table_count ());
198     for (unsigned int i = 0; i < inner_sets.length; i++)
199       inner_sets[i] = hb_set_create ();
200     adv_set = hb_set_create ();
201 
202     inner_maps.resize (var_store->get_sub_table_count ());
203 
204     if (unlikely (!index_map_plans.length || !inner_sets.length || !inner_maps.length)) return;
205 
206     bool retain_adv_map = false;
207     index_map_plans[0].init (*index_maps[0], outer_map, inner_sets, plan, false);
208     if (index_maps[0] == &Null (DeltaSetIndexMap))
209     {
210       retain_adv_map = plan->flags & HB_SUBSET_FLAGS_RETAIN_GIDS;
211       outer_map.add (0);
212       for (hb_codepoint_t old_gid : plan->glyphset()->iter())
213         inner_sets[0]->add (old_gid);
214       hb_set_union (adv_set, inner_sets[0]);
215     }
216 
217     for (unsigned int i = 1; i < index_maps.length; i++)
218       index_map_plans[i].init (*index_maps[i], outer_map, inner_sets, plan);
219 
220     outer_map.sort ();
221 
222     if (retain_adv_map)
223     {
224       for (const auto &_ : plan->new_to_old_gid_list)
225       {
226         hb_codepoint_t old_gid = _.second;
227 	inner_maps[0].add (old_gid);
228       }
229     }
230     else
231     {
232       inner_maps[0].add_set (adv_set);
233       hb_set_subtract (inner_sets[0], adv_set);
234       inner_maps[0].add_set (inner_sets[0]);
235     }
236 
237     for (unsigned int i = 1; i < inner_maps.length; i++)
238       inner_maps[i].add_set (inner_sets[i]);
239 
240     for (unsigned int i = 0; i < index_maps.length; i++)
241       index_map_plans[i].remap (index_maps[i], outer_map, inner_maps, plan);
242   }
243 
244   /* remap */
remap_index_map_plansOT::hvarvvar_subset_plan_t245   bool remap_index_map_plans (const hb_subset_plan_t *plan,
246                               const hb_map_t& varidx_map)
247   {
248     for (unsigned i = 0; i < index_map_plans.length; i++)
249       if (!index_map_plans[i].remap_after_instantiation (plan, varidx_map))
250         return false;
251     return true;
252   }
253 
finiOT::hvarvvar_subset_plan_t254   void fini ()
255   {
256     for (unsigned int i = 0; i < inner_sets.length; i++)
257       hb_set_destroy (inner_sets[i]);
258     hb_set_destroy (adv_set);
259     inner_maps.fini ();
260     index_map_plans.fini ();
261   }
262 
263   hb_inc_bimap_t outer_map;
264   hb_vector_t<hb_inc_bimap_t> inner_maps;
265   hb_vector_t<index_map_subset_plan_t> index_map_plans;
266   const ItemVariationStore *var_store;
267 
268   protected:
269   hb_vector_t<hb_set_t *> inner_sets;
270   hb_set_t *adv_set;
271 };
272 
273 /*
274  * HVAR -- Horizontal Metrics Variations
275  * https://docs.microsoft.com/en-us/typography/opentype/spec/hvar
276  * VVAR -- Vertical Metrics Variations
277  * https://docs.microsoft.com/en-us/typography/opentype/spec/vvar
278  */
279 #define HB_OT_TAG_HVAR HB_TAG('H','V','A','R')
280 #define HB_OT_TAG_VVAR HB_TAG('V','V','A','R')
281 
282 struct HVARVVAR
283 {
284   static constexpr hb_tag_t HVARTag = HB_OT_TAG_HVAR;
285   static constexpr hb_tag_t VVARTag = HB_OT_TAG_VVAR;
286 
sanitizeOT::HVARVVAR287   bool sanitize (hb_sanitize_context_t *c) const
288   {
289     TRACE_SANITIZE (this);
290     return_trace (version.sanitize (c) &&
291 		  hb_barrier () &&
292 		  likely (version.major == 1) &&
293 		  varStore.sanitize (c, this) &&
294 		  advMap.sanitize (c, this) &&
295 		  lsbMap.sanitize (c, this) &&
296 		  rsbMap.sanitize (c, this));
297   }
298 
get_var_storeOT::HVARVVAR299   const ItemVariationStore& get_var_store () const
300   { return this+varStore; }
301 
listup_index_mapsOT::HVARVVAR302   void listup_index_maps (hb_vector_t<const DeltaSetIndexMap *> &index_maps) const
303   {
304     index_maps.push (&(this+advMap));
305     index_maps.push (&(this+lsbMap));
306     index_maps.push (&(this+rsbMap));
307   }
308 
serialize_index_mapsOT::HVARVVAR309   bool serialize_index_maps (hb_serialize_context_t *c,
310 			     const hb_array_t<index_map_subset_plan_t> &im_plans)
311   {
312     TRACE_SERIALIZE (this);
313     if (im_plans[index_map_subset_plan_t::ADV_INDEX].is_identity ())
314       advMap = 0;
315     else if (unlikely (!advMap.serialize_serialize (c, im_plans[index_map_subset_plan_t::ADV_INDEX])))
316       return_trace (false);
317     if (im_plans[index_map_subset_plan_t::LSB_INDEX].is_identity ())
318       lsbMap = 0;
319     else if (unlikely (!lsbMap.serialize_serialize (c, im_plans[index_map_subset_plan_t::LSB_INDEX])))
320       return_trace (false);
321     if (im_plans[index_map_subset_plan_t::RSB_INDEX].is_identity ())
322       rsbMap = 0;
323     else if (unlikely (!rsbMap.serialize_serialize (c, im_plans[index_map_subset_plan_t::RSB_INDEX])))
324       return_trace (false);
325 
326     return_trace (true);
327   }
328 
329   template <typename T>
_subsetOT::HVARVVAR330   bool _subset (hb_subset_context_t *c) const
331   {
332     TRACE_SUBSET (this);
333     if (c->plan->all_axes_pinned)
334       return_trace (false);
335 
336     hvarvvar_subset_plan_t	hvar_plan;
337     hb_vector_t<const DeltaSetIndexMap *>
338 				index_maps;
339 
340     ((T*)this)->listup_index_maps (index_maps);
341     hvar_plan.init (index_maps.as_array (), this+varStore, c->plan);
342 
343     T *out = c->serializer->allocate_min<T> ();
344     if (unlikely (!out)) return_trace (false);
345 
346     out->version.major = 1;
347     out->version.minor = 0;
348 
349     if (c->plan->normalized_coords)
350     {
351       item_variations_t item_vars;
352       if (!item_vars.instantiate (this+varStore, c->plan,
353                                   advMap == 0 ? false : true,
354                                   false, /* use_no_variation_idx = false */
355                                   hvar_plan.inner_maps.as_array ()))
356         return_trace (false);
357 
358       if (!out->varStore.serialize_serialize (c->serializer,
359                                               item_vars.has_long_word (),
360                                               c->plan->axis_tags,
361                                               item_vars.get_region_list (),
362                                               item_vars.get_vardata_encodings ()))
363         return_trace (false);
364 
365       /* if varstore is optimized, remap output_map */
366       if (advMap)
367       {
368         if (!hvar_plan.remap_index_map_plans (c->plan, item_vars.get_varidx_map ()))
369           return_trace (false);
370       }
371     }
372     else
373     {
374       if (unlikely (!out->varStore
375 		    .serialize_serialize (c->serializer,
376 					  hvar_plan.var_store,
377 					  hvar_plan.inner_maps.as_array ())))
378       return_trace (false);
379     }
380 
381     return_trace (out->T::serialize_index_maps (c->serializer,
382 						hvar_plan.index_map_plans.as_array ()));
383   }
384 
get_advance_delta_unscaledOT::HVARVVAR385   float get_advance_delta_unscaled (hb_codepoint_t  glyph,
386 				    const int *coords, unsigned int coord_count,
387 				    ItemVariationStore::cache_t *store_cache = nullptr) const
388   {
389     uint32_t varidx = (this+advMap).map (glyph);
390     return (this+varStore).get_delta (varidx,
391 				      coords, coord_count,
392 				      store_cache);
393   }
394 
get_lsb_delta_unscaledOT::HVARVVAR395   bool get_lsb_delta_unscaled (hb_codepoint_t glyph,
396 			       const int *coords, unsigned int coord_count,
397 			       float *lsb) const
398   {
399     if (!lsbMap) return false;
400     uint32_t varidx = (this+lsbMap).map (glyph);
401     *lsb = (this+varStore).get_delta (varidx, coords, coord_count);
402     return true;
403   }
404 
405   public:
406   FixedVersion<>version;	/* Version of the metrics variation table
407 				 * initially set to 0x00010000u */
408   Offset32To<ItemVariationStore>
409 		varStore;	/* Offset to item variation store table. */
410   Offset32To<DeltaSetIndexMap>
411 		advMap;		/* Offset to advance var-idx mapping. */
412   Offset32To<DeltaSetIndexMap>
413 		lsbMap;		/* Offset to lsb/tsb var-idx mapping. */
414   Offset32To<DeltaSetIndexMap>
415 		rsbMap;		/* Offset to rsb/bsb var-idx mapping. */
416 
417   public:
418   DEFINE_SIZE_STATIC (20);
419 };
420 
421 struct HVAR : HVARVVAR {
422   static constexpr hb_tag_t tableTag = HB_OT_TAG_HVAR;
subsetOT::HVAR423   bool subset (hb_subset_context_t *c) const { return HVARVVAR::_subset<HVAR> (c); }
424 };
425 struct VVAR : HVARVVAR {
426   static constexpr hb_tag_t tableTag = HB_OT_TAG_VVAR;
427 
sanitizeOT::VVAR428   bool sanitize (hb_sanitize_context_t *c) const
429   {
430     TRACE_SANITIZE (this);
431     return_trace (static_cast<const HVARVVAR *> (this)->sanitize (c) &&
432 		  vorgMap.sanitize (c, this));
433   }
434 
listup_index_mapsOT::VVAR435   void listup_index_maps (hb_vector_t<const DeltaSetIndexMap *> &index_maps) const
436   {
437     HVARVVAR::listup_index_maps (index_maps);
438     index_maps.push (&(this+vorgMap));
439   }
440 
serialize_index_mapsOT::VVAR441   bool serialize_index_maps (hb_serialize_context_t *c,
442 			     const hb_array_t<index_map_subset_plan_t> &im_plans)
443   {
444     TRACE_SERIALIZE (this);
445     if (unlikely (!HVARVVAR::serialize_index_maps (c, im_plans)))
446       return_trace (false);
447     if (!im_plans[index_map_subset_plan_t::VORG_INDEX].get_map_count ())
448       vorgMap = 0;
449     else if (unlikely (!vorgMap.serialize_serialize (c, im_plans[index_map_subset_plan_t::VORG_INDEX])))
450       return_trace (false);
451 
452     return_trace (true);
453   }
454 
subsetOT::VVAR455   bool subset (hb_subset_context_t *c) const { return HVARVVAR::_subset<VVAR> (c); }
456 
get_vorg_delta_unscaledOT::VVAR457   bool get_vorg_delta_unscaled (hb_codepoint_t glyph,
458 				const int *coords, unsigned int coord_count,
459 				float *delta) const
460   {
461     if (!vorgMap) return false;
462     uint32_t varidx = (this+vorgMap).map (glyph);
463     *delta = (this+varStore).get_delta (varidx, coords, coord_count);
464     return true;
465   }
466 
467   protected:
468   Offset32To<DeltaSetIndexMap>
469 		vorgMap;	/* Offset to vertical-origin var-idx mapping. */
470 
471   public:
472   DEFINE_SIZE_STATIC (24);
473 };
474 
475 } /* namespace OT */
476 
477 
478 #endif /* HB_OT_VAR_HVAR_TABLE_HH */
479