1 /* 2 * Copyright © 2023 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 */ 25 26 #ifndef HB_OT_VAR_CVAR_TABLE_HH 27 #define HB_OT_VAR_CVAR_TABLE_HH 28 29 #include "hb-ot-var-common.hh" 30 #include "hb-ot-var-fvar-table.hh" 31 32 33 namespace OT { 34 /* 35 * cvar -- control value table (CVT) Variations 36 * https://docs.microsoft.com/en-us/typography/opentype/spec/cvar 37 */ 38 #define HB_OT_TAG_cvar HB_TAG('c','v','a','r') 39 40 struct cvar 41 { 42 static constexpr hb_tag_t tableTag = HB_OT_TAG_cvar; 43 sanitizeOT::cvar44 bool sanitize (hb_sanitize_context_t *c) const 45 { 46 TRACE_SANITIZE (this); 47 return_trace (c->check_struct (this) && 48 version.sanitize (c) && likely (version.major == 1) && 49 tupleVariationData.sanitize (c)); 50 } 51 get_tuple_var_dataOT::cvar52 const TupleVariationData* get_tuple_var_data (void) const 53 { return &tupleVariationData; } 54 decompile_tuple_variationsOT::cvar55 bool decompile_tuple_variations (unsigned axis_count, 56 unsigned point_count, 57 hb_blob_t *blob, 58 bool is_gvar, 59 const hb_map_t *axes_old_index_tag_map, 60 TupleVariationData::tuple_variations_t& tuple_variations /* OUT */) const 61 { 62 hb_vector_t<unsigned> shared_indices; 63 TupleVariationData::tuple_iterator_t iterator; 64 hb_bytes_t var_data_bytes = blob->as_bytes ().sub_array (4); 65 if (!TupleVariationData::get_tuple_iterator (var_data_bytes, axis_count, this, 66 shared_indices, &iterator)) 67 return false; 68 69 return tupleVariationData.decompile_tuple_variations (point_count, is_gvar, iterator, 70 axes_old_index_tag_map, 71 shared_indices, 72 hb_array<const F2DOT14> (), 73 tuple_variations); 74 } 75 calculate_cvt_deltasOT::cvar76 static bool calculate_cvt_deltas (unsigned axis_count, 77 hb_array_t<int> coords, 78 unsigned num_cvt_item, 79 const TupleVariationData *tuple_var_data, 80 const void *base, 81 hb_vector_t<float>& cvt_deltas /* OUT */) 82 { 83 if (!coords) return true; 84 hb_vector_t<unsigned> shared_indices; 85 TupleVariationData::tuple_iterator_t iterator; 86 unsigned var_data_length = tuple_var_data->get_size (axis_count); 87 hb_bytes_t var_data_bytes = hb_bytes_t (reinterpret_cast<const char*> (tuple_var_data), var_data_length); 88 if (!TupleVariationData::get_tuple_iterator (var_data_bytes, axis_count, base, 89 shared_indices, &iterator)) 90 return true; /* isn't applied at all */ 91 92 hb_array_t<const F2DOT14> shared_tuples = hb_array<F2DOT14> (); 93 hb_vector_t<unsigned> private_indices; 94 hb_vector_t<int> unpacked_deltas; 95 96 do 97 { 98 float scalar = iterator.current_tuple->calculate_scalar (coords, axis_count, shared_tuples); 99 if (scalar == 0.f) continue; 100 const HBUINT8 *p = iterator.get_serialized_data (); 101 unsigned int length = iterator.current_tuple->get_data_size (); 102 if (unlikely (!iterator.var_data_bytes.check_range (p, length))) 103 return false; 104 105 const HBUINT8 *end = p + length; 106 107 bool has_private_points = iterator.current_tuple->has_private_points (); 108 if (has_private_points && 109 !TupleVariationData::unpack_points (p, private_indices, end)) 110 return false; 111 const hb_vector_t<unsigned int> &indices = has_private_points ? private_indices : shared_indices; 112 113 bool apply_to_all = (indices.length == 0); 114 unsigned num_deltas = apply_to_all ? num_cvt_item : indices.length; 115 if (unlikely (!unpacked_deltas.resize (num_deltas, false))) return false; 116 if (unlikely (!TupleVariationData::unpack_deltas (p, unpacked_deltas, end))) return false; 117 118 for (unsigned int i = 0; i < num_deltas; i++) 119 { 120 unsigned int idx = apply_to_all ? i : indices[i]; 121 if (unlikely (idx >= num_cvt_item)) continue; 122 if (scalar != 1.0f) cvt_deltas[idx] += unpacked_deltas[i] * scalar ; 123 else cvt_deltas[idx] += unpacked_deltas[i]; 124 } 125 } while (iterator.move_to_next ()); 126 127 return true; 128 } 129 serializeOT::cvar130 bool serialize (hb_serialize_context_t *c, 131 TupleVariationData::tuple_variations_t& tuple_variations) const 132 { 133 TRACE_SERIALIZE (this); 134 if (!tuple_variations) return_trace (false); 135 if (unlikely (!c->embed (version))) return_trace (false); 136 137 return_trace (tupleVariationData.serialize (c, false, tuple_variations)); 138 } 139 subsetOT::cvar140 bool subset (hb_subset_context_t *c) const 141 { 142 TRACE_SUBSET (this); 143 if (c->plan->all_axes_pinned) 144 return_trace (false); 145 146 OT::TupleVariationData::tuple_variations_t tuple_variations; 147 unsigned axis_count = c->plan->axes_old_index_tag_map.get_population (); 148 149 const hb_tag_t cvt = HB_TAG('c','v','t',' '); 150 hb_blob_t *cvt_blob = hb_face_reference_table (c->plan->source, cvt); 151 unsigned point_count = hb_blob_get_length (cvt_blob) / FWORD::static_size; 152 hb_blob_destroy (cvt_blob); 153 154 if (!decompile_tuple_variations (axis_count, point_count, 155 c->source_blob, false, 156 &(c->plan->axes_old_index_tag_map), 157 tuple_variations)) 158 return_trace (false); 159 160 if (!tuple_variations.instantiate (c->plan->axes_location, c->plan->axes_triple_distances)) 161 return_trace (false); 162 163 if (!tuple_variations.compile_bytes (c->plan->axes_index_map, c->plan->axes_old_index_tag_map, 164 false /* do not use shared points */)) 165 return_trace (false); 166 167 return_trace (serialize (c->serializer, tuple_variations)); 168 } 169 add_cvt_and_apply_deltasOT::cvar170 static bool add_cvt_and_apply_deltas (hb_subset_plan_t *plan, 171 const TupleVariationData *tuple_var_data, 172 const void *base) 173 { 174 const hb_tag_t cvt = HB_TAG('c','v','t',' '); 175 hb_blob_t *cvt_blob = hb_face_reference_table (plan->source, cvt); 176 hb_blob_t *cvt_prime_blob = hb_blob_copy_writable_or_fail (cvt_blob); 177 hb_blob_destroy (cvt_blob); 178 179 if (unlikely (!cvt_prime_blob)) 180 return false; 181 182 unsigned cvt_blob_length = hb_blob_get_length (cvt_prime_blob); 183 unsigned num_cvt_item = cvt_blob_length / FWORD::static_size; 184 185 hb_vector_t<float> cvt_deltas; 186 if (unlikely (!cvt_deltas.resize (num_cvt_item))) 187 { 188 hb_blob_destroy (cvt_prime_blob); 189 return false; 190 } 191 192 if (!calculate_cvt_deltas (plan->normalized_coords.length, plan->normalized_coords.as_array (), 193 num_cvt_item, tuple_var_data, base, cvt_deltas)) 194 { 195 hb_blob_destroy (cvt_prime_blob); 196 return false; 197 } 198 199 FWORD *cvt_prime = (FWORD *) hb_blob_get_data_writable (cvt_prime_blob, nullptr); 200 for (unsigned i = 0; i < num_cvt_item; i++) 201 cvt_prime[i] += (int) roundf (cvt_deltas[i]); 202 203 bool success = plan->add_table (cvt, cvt_prime_blob); 204 hb_blob_destroy (cvt_prime_blob); 205 return success; 206 } 207 208 protected: 209 FixedVersion<>version; /* Version of the CVT variation table 210 * initially set to 0x00010000u */ 211 TupleVariationData tupleVariationData; /* TupleVariationDate for cvar table */ 212 public: 213 DEFINE_SIZE_MIN (8); 214 }; 215 216 } /* namespace OT */ 217 218 219 #endif /* HB_OT_VAR_CVAR_TABLE_HH */ 220