harfbuzz/src/hb-ot-var-mvar-table.hh

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/*
* Copyright © 2017 Google, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Google Author(s): Behdad Esfahbod
*/
#ifndef HB_OT_VAR_MVAR_TABLE_HH
#define HB_OT_VAR_MVAR_TABLE_HH
#include "hb-ot-layout-common.hh"
namespace OT {
struct VariationValueRecord
{
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (c->check_struct (this));
}
public:
Tag valueTag; /* Four-byte tag identifying a font-wide measure. */
HBUINT32 varIdx; /* Outer/inner index into VariationStore item. */
public:
DEFINE_SIZE_STATIC (8);
};
/*
* MVAR -- Metrics Variations
* https://docs.microsoft.com/en-us/typography/opentype/spec/mvar
*/
#define HB_OT_TAG_MVAR HB_TAG('M','V','A','R')
struct MVAR
{
static constexpr hb_tag_t tableTag = HB_OT_TAG_MVAR;
bool sanitize (hb_sanitize_context_t *c) const
{
TRACE_SANITIZE (this);
return_trace (version.sanitize (c) &&
likely (version.major == 1) &&
c->check_struct (this) &&
valueRecordSize >= VariationValueRecord::static_size &&
varStore.sanitize (c, this) &&
c->check_range (valuesZ.arrayZ,
valueRecordCount,
valueRecordSize));
}
float get_var (hb_tag_t tag,
const int *coords, unsigned int coord_count) const
{
const VariationValueRecord *record;
record = (VariationValueRecord *) bsearch (&tag, valuesZ.arrayZ,
valueRecordCount, valueRecordSize,
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tag_compare);
if (!record)
return 0.;
return (this+varStore).get_delta (record->varIdx, coords, coord_count);
}
protected:
static int tag_compare (const void *pa, const void *pb)
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{
const hb_tag_t *a = (const hb_tag_t *) pa;
const Tag *b = (const Tag *) pb;
return b->cmp (*a);
}
protected:
FixedVersion<>version; /* Version of the metrics variation table
* initially set to 0x00010000u */
HBUINT16 reserved; /* Not used; set to 0. */
HBUINT16 valueRecordSize;/* The size in bytes of each value record —
* must be greater than zero. */
HBUINT16 valueRecordCount;/* The number of value records — may be zero. */
OffsetTo<VariationStore>
varStore; /* Offset to item variation store table. */
UnsizedArrayOf<HBUINT8>
valuesZ; /* Array of value records. The records must be
* in binary order of their valueTag field. */
public:
DEFINE_SIZE_ARRAY (12, valuesZ);
};
} /* namespace OT */
#endif /* HB_OT_VAR_MVAR_TABLE_HH */