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_MVAR_TABLE_HH 28 #define HB_OT_VAR_MVAR_TABLE_HH 29 30 #include "hb-ot-layout-common.hh" 31 32 33 namespace OT { 34 35 36 struct VariationValueRecord 37 { sanitizeOT::VariationValueRecord38 bool sanitize (hb_sanitize_context_t *c) const 39 { 40 TRACE_SANITIZE (this); 41 return_trace (c->check_struct (this)); 42 } 43 44 public: 45 Tag valueTag; /* Four-byte tag identifying a font-wide measure. */ 46 HBUINT32 varIdx; /* Outer/inner index into VariationStore item. */ 47 48 public: 49 DEFINE_SIZE_STATIC (8); 50 }; 51 52 53 /* 54 * MVAR -- Metrics Variations 55 * https://docs.microsoft.com/en-us/typography/opentype/spec/mvar 56 */ 57 #define HB_OT_TAG_MVAR HB_TAG('M','V','A','R') 58 59 struct MVAR 60 { 61 static constexpr hb_tag_t tableTag = HB_OT_TAG_MVAR; 62 sanitizeOT::MVAR63 bool sanitize (hb_sanitize_context_t *c) const 64 { 65 TRACE_SANITIZE (this); 66 return_trace (version.sanitize (c) && 67 likely (version.major == 1) && 68 c->check_struct (this) && 69 valueRecordSize >= VariationValueRecord::static_size && 70 varStore.sanitize (c, this) && 71 c->check_range (valuesZ.arrayZ, 72 valueRecordCount, 73 valueRecordSize)); 74 } 75 get_varOT::MVAR76 float get_var (hb_tag_t tag, 77 const int *coords, unsigned int coord_count) const 78 { 79 const VariationValueRecord *record; 80 record = (VariationValueRecord *) hb_bsearch (tag, 81 (const VariationValueRecord *) 82 (const HBUINT8 *) valuesZ, 83 valueRecordCount, valueRecordSize, 84 tag_compare); 85 if (!record) 86 return 0.; 87 88 return (this+varStore).get_delta (record->varIdx, coords, coord_count); 89 } 90 91 protected: tag_compareOT::MVAR92 static int tag_compare (const void *pa, const void *pb) 93 { 94 const hb_tag_t *a = (const hb_tag_t *) pa; 95 const Tag *b = (const Tag *) pb; 96 return b->cmp (*a); 97 } 98 99 protected: 100 FixedVersion<>version; /* Version of the metrics variation table 101 * initially set to 0x00010000u */ 102 HBUINT16 reserved; /* Not used; set to 0. */ 103 HBUINT16 valueRecordSize;/* The size in bytes of each value record — 104 * must be greater than zero. */ 105 HBUINT16 valueRecordCount;/* The number of value records — may be zero. */ 106 Offset16To<VariationStore> 107 varStore; /* Offset to item variation store table. */ 108 UnsizedArrayOf<HBUINT8> 109 valuesZ; /* Array of value records. The records must be 110 * in binary order of their valueTag field. */ 111 112 public: 113 DEFINE_SIZE_ARRAY (12, valuesZ); 114 }; 115 116 } /* namespace OT */ 117 118 119 #endif /* HB_OT_VAR_MVAR_TABLE_HH */ 120