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/*
* Copyright (c) 2020, Srimanta Barua <srimanta.barua1@gmail.com>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#pragma once
#include <AK/Span.h>
namespace TTF {
enum class IndexToLocFormat {
Offset16,
Offset32,
};
class Head {
public:
static Optional<Head> from_slice(const ReadonlyBytes&);
u16 units_per_em() const;
i16 xmin() const;
i16 ymin() const;
i16 xmax() const;
i16 ymax() const;
u16 lowest_recommended_ppem() const;
IndexToLocFormat index_to_loc_format() const;
private:
enum class Offsets {
UnitsPerEM = 18,
XMin = 36,
YMin = 38,
XMax = 40,
YMax = 42,
LowestRecPPEM = 46,
IndexToLocFormat = 50,
};
enum class Sizes {
Table = 54,
};
Head(const ReadonlyBytes& slice)
: m_slice(slice)
{
}
ReadonlyBytes m_slice;
};
class Hhea {
public:
static Optional<Hhea> from_slice(const ReadonlyBytes&);
i16 ascender() const;
i16 descender() const;
i16 line_gap() const;
u16 advance_width_max() const;
u16 number_of_h_metrics() const;
private:
enum class Offsets {
Ascender = 4,
Descender = 6,
LineGap = 8,
AdvanceWidthMax = 10,
NumberOfHMetrics = 34,
};
enum class Sizes {
Table = 36,
};
Hhea(const ReadonlyBytes& slice)
: m_slice(slice)
{
}
ReadonlyBytes m_slice;
};
class Maxp {
public:
static Optional<Maxp> from_slice(const ReadonlyBytes&);
u16 num_glyphs() const;
private:
enum class Offsets {
NumGlyphs = 4
};
enum class Sizes {
TableV0p5 = 6,
};
Maxp(const ReadonlyBytes& slice)
: m_slice(slice)
{
}
ReadonlyBytes m_slice;
};
struct GlyphHorizontalMetrics {
u16 advance_width;
i16 left_side_bearing;
};
class Hmtx {
public:
static Optional<Hmtx> from_slice(const ReadonlyBytes&, u32 num_glyphs, u32 number_of_h_metrics);
GlyphHorizontalMetrics get_glyph_horizontal_metrics(u32 glyph_id) const;
private:
enum class Sizes {
LongHorMetric = 4,
LeftSideBearing = 2
};
Hmtx(const ReadonlyBytes& slice, u32 num_glyphs, u32 number_of_h_metrics)
: m_slice(slice)
, m_num_glyphs(num_glyphs)
, m_number_of_h_metrics(number_of_h_metrics)
{
}
ReadonlyBytes m_slice;
u32 m_num_glyphs { 0 };
u32 m_number_of_h_metrics { 0 };
};
}
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