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_FVAR_TABLE_HH 28 #define HB_OT_VAR_FVAR_TABLE_HH 29 30 #include "hb-open-type.hh" 31 32 /* 33 * fvar -- Font Variations 34 * https://docs.microsoft.com/en-us/typography/opentype/spec/fvar 35 */ 36 37 #define HB_OT_TAG_fvar HB_TAG('f','v','a','r') 38 39 40 namespace OT { 41 42 43 struct InstanceRecord 44 { 45 friend struct fvar; 46 get_coordinatesOT::InstanceRecord47 hb_array_t<const HBFixed> get_coordinates (unsigned int axis_count) const 48 { return coordinatesZ.as_array (axis_count); } 49 sanitizeOT::InstanceRecord50 bool sanitize (hb_sanitize_context_t *c, unsigned int axis_count) const 51 { 52 TRACE_SANITIZE (this); 53 return_trace (c->check_struct (this) && 54 c->check_array (coordinatesZ.arrayZ, axis_count)); 55 } 56 57 protected: 58 NameID subfamilyNameID;/* The name ID for entries in the 'name' table 59 * that provide subfamily names for this instance. */ 60 HBUINT16 flags; /* Reserved for future use — set to 0. */ 61 UnsizedArrayOf<HBFixed> 62 coordinatesZ; /* The coordinates array for this instance. */ 63 //NameID postScriptNameIDX;/*Optional. The name ID for entries in the 'name' 64 // * table that provide PostScript names for this 65 // * instance. */ 66 67 public: 68 DEFINE_SIZE_UNBOUNDED (4); 69 }; 70 71 struct AxisRecord 72 { 73 enum 74 { 75 AXIS_FLAG_HIDDEN = 0x0001, 76 }; 77 sanitizeOT::AxisRecord78 bool sanitize (hb_sanitize_context_t *c) const 79 { 80 TRACE_SANITIZE (this); 81 return_trace (c->check_struct (this)); 82 } 83 84 public: 85 Tag axisTag; /* Tag identifying the design variation for the axis. */ 86 HBFixed minValue; /* The minimum coordinate value for the axis. */ 87 HBFixed defaultValue; /* The default coordinate value for the axis. */ 88 HBFixed maxValue; /* The maximum coordinate value for the axis. */ 89 HBUINT16 flags; /* Axis flags. */ 90 NameID axisNameID; /* The name ID for entries in the 'name' table that 91 * provide a display name for this axis. */ 92 93 public: 94 DEFINE_SIZE_STATIC (20); 95 }; 96 97 struct fvar 98 { 99 static constexpr hb_tag_t tableTag = HB_OT_TAG_fvar; 100 has_dataOT::fvar101 bool has_data () const { return version.to_int (); } 102 sanitizeOT::fvar103 bool sanitize (hb_sanitize_context_t *c) const 104 { 105 TRACE_SANITIZE (this); 106 return_trace (version.sanitize (c) && 107 likely (version.major == 1) && 108 c->check_struct (this) && 109 axisSize == 20 && /* Assumed in our code. */ 110 instanceSize >= axisCount * 4 + 4 && 111 get_axes ().sanitize (c) && 112 c->check_range (get_instance (0), instanceCount, instanceSize)); 113 } 114 get_axis_countOT::fvar115 unsigned int get_axis_count () const { return axisCount; } 116 117 #ifndef HB_DISABLE_DEPRECATED get_axis_deprecatedOT::fvar118 void get_axis_deprecated (unsigned int axis_index, 119 hb_ot_var_axis_t *info) const 120 { 121 const AxisRecord &axis = get_axes ()[axis_index]; 122 info->tag = axis.axisTag; 123 info->name_id = axis.axisNameID; 124 info->default_value = axis.defaultValue / 65536.f; 125 /* Ensure order, to simplify client math. */ 126 info->min_value = hb_min (info->default_value, axis.minValue / 65536.f); 127 info->max_value = hb_max (info->default_value, axis.maxValue / 65536.f); 128 } 129 #endif 130 get_axis_infoOT::fvar131 void get_axis_info (unsigned int axis_index, 132 hb_ot_var_axis_info_t *info) const 133 { 134 const AxisRecord &axis = get_axes ()[axis_index]; 135 info->axis_index = axis_index; 136 info->tag = axis.axisTag; 137 info->name_id = axis.axisNameID; 138 info->flags = (hb_ot_var_axis_flags_t) (unsigned int) axis.flags; 139 info->default_value = axis.defaultValue / 65536.f; 140 /* Ensure order, to simplify client math. */ 141 info->min_value = hb_min (info->default_value, axis.minValue / 65536.f); 142 info->max_value = hb_max (info->default_value, axis.maxValue / 65536.f); 143 info->reserved = 0; 144 } 145 146 #ifndef HB_DISABLE_DEPRECATED get_axes_deprecatedOT::fvar147 unsigned int get_axes_deprecated (unsigned int start_offset, 148 unsigned int *axes_count /* IN/OUT */, 149 hb_ot_var_axis_t *axes_array /* OUT */) const 150 { 151 if (axes_count) 152 { 153 /* TODO Rewrite as hb_array_t<>::sub-array() */ 154 unsigned int count = axisCount; 155 start_offset = hb_min (start_offset, count); 156 157 count -= start_offset; 158 axes_array += start_offset; 159 160 count = hb_min (count, *axes_count); 161 *axes_count = count; 162 163 for (unsigned int i = 0; i < count; i++) 164 get_axis_deprecated (start_offset + i, axes_array + i); 165 } 166 return axisCount; 167 } 168 #endif 169 get_axis_infosOT::fvar170 unsigned int get_axis_infos (unsigned int start_offset, 171 unsigned int *axes_count /* IN/OUT */, 172 hb_ot_var_axis_info_t *axes_array /* OUT */) const 173 { 174 if (axes_count) 175 { 176 /* TODO Rewrite as hb_array_t<>::sub-array() */ 177 unsigned int count = axisCount; 178 start_offset = hb_min (start_offset, count); 179 180 count -= start_offset; 181 axes_array += start_offset; 182 183 count = hb_min (count, *axes_count); 184 *axes_count = count; 185 186 for (unsigned int i = 0; i < count; i++) 187 get_axis_info (start_offset + i, axes_array + i); 188 } 189 return axisCount; 190 } 191 192 #ifndef HB_DISABLE_DEPRECATED find_axis_deprecatedOT::fvar193 bool find_axis_deprecated (hb_tag_t tag, 194 unsigned int *axis_index, 195 hb_ot_var_axis_t *info) const 196 { 197 const AxisRecord *axes = get_axes (); 198 unsigned int count = get_axis_count (); 199 for (unsigned int i = 0; i < count; i++) 200 if (axes[i].axisTag == tag) 201 { 202 if (axis_index) 203 *axis_index = i; 204 get_axis_deprecated (i, info); 205 return true; 206 } 207 if (axis_index) 208 *axis_index = HB_OT_VAR_NO_AXIS_INDEX; 209 return false; 210 } 211 #endif 212 find_axis_infoOT::fvar213 bool find_axis_info (hb_tag_t tag, 214 hb_ot_var_axis_info_t *info) const 215 { 216 const AxisRecord *axes = get_axes (); 217 unsigned int count = get_axis_count (); 218 for (unsigned int i = 0; i < count; i++) 219 if (axes[i].axisTag == tag) 220 { 221 get_axis_info (i, info); 222 return true; 223 } 224 return false; 225 } 226 normalize_axis_valueOT::fvar227 int normalize_axis_value (unsigned int axis_index, float v) const 228 { 229 hb_ot_var_axis_info_t axis; 230 get_axis_info (axis_index, &axis); 231 232 v = hb_max (hb_min (v, axis.max_value), axis.min_value); /* Clamp. */ 233 234 if (v == axis.default_value) 235 return 0; 236 else if (v < axis.default_value) 237 v = (v - axis.default_value) / (axis.default_value - axis.min_value); 238 else 239 v = (v - axis.default_value) / (axis.max_value - axis.default_value); 240 return roundf (v * 16384.f); 241 } 242 unnormalize_axis_valueOT::fvar243 float unnormalize_axis_value (unsigned int axis_index, float v) const 244 { 245 hb_ot_var_axis_info_t axis; 246 get_axis_info (axis_index, &axis); 247 248 if (v == 0) 249 return axis.default_value; 250 else if (v < 0) 251 v = v * (axis.default_value - axis.min_value) / 16384.f + axis.default_value; 252 else 253 v = v * (axis.max_value - axis.default_value) / 16384.f + axis.default_value; 254 return v; 255 } 256 get_instance_countOT::fvar257 unsigned int get_instance_count () const { return instanceCount; } 258 get_instance_subfamily_name_idOT::fvar259 hb_ot_name_id_t get_instance_subfamily_name_id (unsigned int instance_index) const 260 { 261 const InstanceRecord *instance = get_instance (instance_index); 262 if (unlikely (!instance)) return HB_OT_NAME_ID_INVALID; 263 return instance->subfamilyNameID; 264 } 265 get_instance_postscript_name_idOT::fvar266 hb_ot_name_id_t get_instance_postscript_name_id (unsigned int instance_index) const 267 { 268 const InstanceRecord *instance = get_instance (instance_index); 269 if (unlikely (!instance)) return HB_OT_NAME_ID_INVALID; 270 if (instanceSize >= axisCount * 4 + 6) 271 return StructAfter<NameID> (instance->get_coordinates (axisCount)); 272 return HB_OT_NAME_ID_INVALID; 273 } 274 get_instance_coordsOT::fvar275 unsigned int get_instance_coords (unsigned int instance_index, 276 unsigned int *coords_length, /* IN/OUT */ 277 float *coords /* OUT */) const 278 { 279 const InstanceRecord *instance = get_instance (instance_index); 280 if (unlikely (!instance)) 281 { 282 if (coords_length) 283 *coords_length = 0; 284 return 0; 285 } 286 287 if (coords_length && *coords_length) 288 { 289 hb_array_t<const HBFixed> instanceCoords = instance->get_coordinates (axisCount) 290 .sub_array (0, *coords_length); 291 for (unsigned int i = 0; i < instanceCoords.length; i++) 292 coords[i] = instanceCoords.arrayZ[i].to_float (); 293 } 294 return axisCount; 295 } 296 collect_name_idsOT::fvar297 void collect_name_ids (hb_set_t *nameids) const 298 { 299 if (!has_data ()) return; 300 301 + get_axes () 302 | hb_map (&AxisRecord::axisNameID) 303 | hb_sink (nameids) 304 ; 305 306 + hb_range ((unsigned) instanceCount) 307 | hb_map ([this] (const unsigned _) { return get_instance_subfamily_name_id (_); }) 308 | hb_sink (nameids) 309 ; 310 311 + hb_range ((unsigned) instanceCount) 312 | hb_map ([this] (const unsigned _) { return get_instance_postscript_name_id (_); }) 313 | hb_sink (nameids) 314 ; 315 } 316 317 318 protected: get_axesOT::fvar319 hb_array_t<const AxisRecord> get_axes () const 320 { return hb_array (&(this+firstAxis), axisCount); } 321 get_instanceOT::fvar322 const InstanceRecord *get_instance (unsigned int i) const 323 { 324 if (unlikely (i >= instanceCount)) return nullptr; 325 return &StructAtOffset<InstanceRecord> (&StructAfter<InstanceRecord> (get_axes ()), 326 i * instanceSize); 327 } 328 329 protected: 330 FixedVersion<>version; /* Version of the fvar table 331 * initially set to 0x00010000u */ 332 OffsetTo<AxisRecord> 333 firstAxis; /* Offset in bytes from the beginning of the table 334 * to the start of the AxisRecord array. */ 335 HBUINT16 reserved; /* This field is permanently reserved. Set to 2. */ 336 HBUINT16 axisCount; /* The number of variation axes in the font (the 337 * number of records in the axes array). */ 338 HBUINT16 axisSize; /* The size in bytes of each VariationAxisRecord — 339 * set to 20 (0x0014) for this version. */ 340 HBUINT16 instanceCount; /* The number of named instances defined in the font 341 * (the number of records in the instances array). */ 342 HBUINT16 instanceSize; /* The size in bytes of each InstanceRecord — set 343 * to either axisCount * sizeof(HBFixed) + 4, or to 344 * axisCount * sizeof(HBFixed) + 6. */ 345 346 public: 347 DEFINE_SIZE_STATIC (16); 348 }; 349 350 } /* namespace OT */ 351 352 353 #endif /* HB_OT_VAR_FVAR_TABLE_HH */ 354