ladybird/Libraries/LibGfx/Font/Font.h

102 lines
2.5 KiB
C++

/*
* Copyright (c) 2020, Stephan Unverwerth <s.unverwerth@serenityos.org>
* Copyright (c) 2023, Andreas Kling <andreas@ladybird.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#pragma once
#include <AK/Bitmap.h>
#include <AK/ByteReader.h>
#include <AK/RefCounted.h>
#include <AK/RefPtr.h>
#include <AK/String.h>
#include <AK/Types.h>
#include <LibCore/MappedFile.h>
#include <LibGfx/Bitmap.h>
#include <LibGfx/Size.h>
struct hb_font_t;
namespace Gfx {
struct FontPixelMetrics {
float size { 0 };
float x_height { 0 };
float advance_of_ascii_zero { 0 };
// Number of pixels the font extends above the baseline.
float ascent { 0 };
// Number of pixels the font descends below the baseline.
float descent { 0 };
// Line gap specified by font.
float line_gap { 0 };
float line_spacing() const { return ascent + descent + line_gap; }
};
// https://learn.microsoft.com/en-us/typography/opentype/spec/os2#uswidthclass
enum FontWidth {
UltraCondensed = 1,
ExtraCondensed = 2,
Condensed = 3,
SemiCondensed = 4,
Normal = 5,
SemiExpanded = 6,
Expanded = 7,
ExtraExpanded = 8,
UltraExpanded = 9
};
constexpr float text_shaping_resolution = 64;
class Typeface;
class Font : public RefCounted<Font> {
public:
virtual ~Font();
virtual FontPixelMetrics pixel_metrics() const = 0;
virtual u8 slope() const = 0;
// Font point size (distance between ascender and descender).
virtual float point_size() const = 0;
// Font pixel size (distance between ascender and descender).
virtual float pixel_size() const = 0;
// Font pixel size, rounded up to the nearest integer.
virtual int pixel_size_rounded_up() const = 0;
virtual u16 weight() const = 0;
virtual bool contains_glyph(u32 code_point) const = 0;
virtual u32 glyph_id_for_code_point(u32 code_point) const = 0;
virtual float glyph_width(u32 code_point) const = 0;
virtual int x_height() const = 0;
virtual float preferred_line_height() const = 0;
virtual u8 baseline() const = 0;
virtual float width(StringView) const = 0;
virtual float width(Utf8View const&) const = 0;
virtual FlyString family() const = 0;
virtual NonnullRefPtr<Font> with_size(float point_size) const = 0;
Font const& bold_variant() const;
hb_font_t* harfbuzz_font() const;
virtual Typeface const& typeface() const = 0;
private:
mutable RefPtr<Gfx::Font const> m_bold_variant;
mutable hb_font_t* m_harfbuzz_font { nullptr };
};
}