hb-ot-var-cvar-table.hh (8658B)
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 44 bool sanitize (hb_sanitize_context_t *c) const 45 { 46 TRACE_SANITIZE (this); 47 return_trace (c->check_struct (this) && 48 hb_barrier () && 49 likely (version.major == 1) && 50 tupleVariationData.sanitize (c)); 51 } 52 53 const TupleVariationData<>* get_tuple_var_data (void) const 54 { return &tupleVariationData; } 55 56 bool decompile_tuple_variations (unsigned axis_count, 57 unsigned point_count, 58 hb_blob_t *blob, 59 bool is_gvar, 60 const hb_map_t *axes_old_index_tag_map, 61 TupleVariationData<>::tuple_variations_t& tuple_variations /* OUT */) const 62 { 63 hb_vector_t<unsigned> shared_indices; 64 TupleVariationData<>::tuple_iterator_t iterator; 65 hb_bytes_t var_data_bytes = blob->as_bytes ().sub_array (4); 66 if (!TupleVariationData<>::get_tuple_iterator (var_data_bytes, axis_count, this, 67 shared_indices, &iterator)) 68 return false; 69 70 return tupleVariationData.decompile_tuple_variations (point_count, is_gvar, iterator, 71 axes_old_index_tag_map, 72 shared_indices, 73 hb_array<const F2DOT14> (), 74 tuple_variations); 75 } 76 77 static bool calculate_cvt_deltas (unsigned axis_count, 78 hb_array_t<int> coords, 79 unsigned num_cvt_item, 80 const TupleVariationData<> *tuple_var_data, 81 const void *base, 82 hb_vector_t<float>& cvt_deltas /* OUT */) 83 { 84 if (!coords) return true; 85 hb_vector_t<unsigned> shared_indices; 86 TupleVariationData<>::tuple_iterator_t iterator; 87 unsigned var_data_length = tuple_var_data->get_size (axis_count * 2); 88 hb_bytes_t var_data_bytes = hb_bytes_t (reinterpret_cast<const char*> (tuple_var_data), var_data_length); 89 if (!TupleVariationData<>::get_tuple_iterator (var_data_bytes, axis_count, base, 90 shared_indices, &iterator)) 91 return true; /* isn't applied at all */ 92 93 hb_array_t<const F2DOT14> shared_tuples = hb_array<F2DOT14> (); 94 hb_vector_t<unsigned> private_indices; 95 hb_vector_t<int> unpacked_deltas; 96 97 do 98 { 99 float scalar = iterator.current_tuple->calculate_scalar (coords, axis_count, shared_tuples); 100 if (scalar == 0.f) continue; 101 const HBUINT8 *p = iterator.get_serialized_data (); 102 unsigned int length = iterator.current_tuple->get_data_size (); 103 if (unlikely (!iterator.var_data_bytes.check_range (p, length))) 104 return false; 105 106 const HBUINT8 *end = p + length; 107 108 bool has_private_points = iterator.current_tuple->has_private_points (); 109 if (has_private_points && 110 !TupleVariationData<>::decompile_points (p, private_indices, end)) 111 return false; 112 const hb_vector_t<unsigned int> &indices = has_private_points ? private_indices : shared_indices; 113 114 bool apply_to_all = (indices.length == 0); 115 unsigned num_deltas = apply_to_all ? num_cvt_item : indices.length; 116 if (unlikely (!unpacked_deltas.resize_dirty (num_deltas))) return false; 117 if (unlikely (!TupleVariationData<>::decompile_deltas (p, unpacked_deltas, end))) return false; 118 119 for (unsigned int i = 0; i < num_deltas; i++) 120 { 121 unsigned int idx = apply_to_all ? i : indices[i]; 122 if (unlikely (idx >= num_cvt_item)) continue; 123 if (scalar != 1.0f) cvt_deltas[idx] += unpacked_deltas[i] * scalar ; 124 else cvt_deltas[idx] += unpacked_deltas[i]; 125 } 126 } while (iterator.move_to_next ()); 127 128 return true; 129 } 130 131 bool serialize (hb_serialize_context_t *c, 132 TupleVariationData<>::tuple_variations_t& tuple_variations) const 133 { 134 TRACE_SERIALIZE (this); 135 if (!tuple_variations) return_trace (false); 136 if (unlikely (!c->embed (version))) return_trace (false); 137 138 return_trace (tupleVariationData.serialize (c, false, tuple_variations)); 139 } 140 141 bool subset (hb_subset_context_t *c) const 142 { 143 TRACE_SUBSET (this); 144 if (c->plan->all_axes_pinned) 145 return_trace (false); 146 147 OT::TupleVariationData<>::tuple_variations_t tuple_variations; 148 unsigned axis_count = c->plan->axes_old_index_tag_map.get_population (); 149 150 const hb_tag_t cvt = HB_TAG('c','v','t',' '); 151 hb_blob_t *cvt_blob = hb_face_reference_table (c->plan->source, cvt); 152 unsigned point_count = hb_blob_get_length (cvt_blob) / FWORD::static_size; 153 hb_blob_destroy (cvt_blob); 154 155 if (!decompile_tuple_variations (axis_count, point_count, 156 c->source_blob, false, 157 &(c->plan->axes_old_index_tag_map), 158 tuple_variations)) 159 return_trace (false); 160 161 optimize_scratch_t scratch; 162 if (!tuple_variations.instantiate (c->plan->axes_location, c->plan->axes_triple_distances, scratch)) 163 return_trace (false); 164 165 if (!tuple_variations.compile_bytes (c->plan->axes_index_map, c->plan->axes_old_index_tag_map, 166 false /* do not use shared points */)) 167 return_trace (false); 168 169 return_trace (serialize (c->serializer, tuple_variations)); 170 } 171 172 static bool add_cvt_and_apply_deltas (hb_subset_plan_t *plan, 173 const TupleVariationData<> *tuple_var_data, 174 const void *base) 175 { 176 const hb_tag_t cvt = HB_TAG('c','v','t',' '); 177 hb_blob_t *cvt_blob = hb_face_reference_table (plan->source, cvt); 178 hb_blob_t *cvt_prime_blob = hb_blob_copy_writable_or_fail (cvt_blob); 179 hb_blob_destroy (cvt_blob); 180 181 if (unlikely (!cvt_prime_blob)) 182 return false; 183 184 unsigned cvt_blob_length = hb_blob_get_length (cvt_prime_blob); 185 unsigned num_cvt_item = cvt_blob_length / FWORD::static_size; 186 187 hb_vector_t<float> cvt_deltas; 188 if (unlikely (!cvt_deltas.resize (num_cvt_item))) 189 { 190 hb_blob_destroy (cvt_prime_blob); 191 return false; 192 } 193 194 if (!calculate_cvt_deltas (plan->normalized_coords.length, plan->normalized_coords.as_array (), 195 num_cvt_item, tuple_var_data, base, cvt_deltas)) 196 { 197 hb_blob_destroy (cvt_prime_blob); 198 return false; 199 } 200 201 FWORD *cvt_prime = (FWORD *) hb_blob_get_data_writable (cvt_prime_blob, nullptr); 202 for (unsigned i = 0; i < num_cvt_item; i++) 203 cvt_prime[i] += (int) roundf (cvt_deltas[i]); 204 205 bool success = plan->add_table (cvt, cvt_prime_blob); 206 hb_blob_destroy (cvt_prime_blob); 207 return success; 208 } 209 210 protected: 211 FixedVersion<>version; /* Version of the CVT variation table 212 * initially set to 0x00010000u */ 213 TupleVariationData<> tupleVariationData; /* TupleVariationDate for cvar table */ 214 public: 215 DEFINE_SIZE_MIN (8); 216 }; 217 218 } /* namespace OT */ 219 220 221 #endif /* HB_OT_VAR_CVAR_TABLE_HH */