chromium/third_party/blink/renderer/platform/fonts/shaping/han_kerning.cc

// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "third_party/blink/renderer/platform/fonts/shaping/han_kerning.h"

#include <unicode/uchar.h>

#include "third_party/blink/renderer/platform/fonts/opentype/open_type_features.h"
#include "third_party/blink/renderer/platform/fonts/shaping/font_features.h"
#include "third_party/blink/renderer/platform/fonts/shaping/harfbuzz_shaper.h"
#include "third_party/blink/renderer/platform/fonts/simple_font_data.h"
#include "third_party/blink/renderer/platform/wtf/text/character_names.h"

namespace blink {

namespace {

HashSet<uint32_t> ExclusiveFeatures() { … }

bool IsExclusiveFeature(uint32_t tag) { … }

inline float GetAdvance(const HarfBuzzShaper::GlyphData& glyph,
                        bool is_horizontal) { … }

// Compute `CharType` from the glyph bounding box.
HanKerning::CharType CharTypeFromBounds(float half_em,
                                        const SkRect& bound,
                                        bool is_horizontal) { … }

HanKerning::CharType CharTypeFromBounds(
    base::span<HarfBuzzShaper::GlyphData> glyphs,
    base::span<SkRect> bounds,
    unsigned index,
    bool is_horizontal) { … }

HanKerning::CharType CharTypeFromBounds(
    base::span<HarfBuzzShaper::GlyphData> glyphs,
    base::span<SkRect> bounds,
    bool is_horizontal) { … }

}  // namespace

void HanKerning::ResetFeatures() { … }

// Compute the character class.
// See Text Spacing Character Classes:
// https://drafts.csswg.org/css-text-4/#text-spacing-classes
HanKerning::CharType HanKerning::GetCharType(UChar ch,
                                             const FontData& font_data) { … }

bool HanKerning::MayApply(StringView text) { … }

inline bool HanKerning::ShouldKern(CharType type, CharType last_type) { … }

inline bool HanKerning::ShouldKernLast(CharType type, CharType last_type) { … }

// Compute kerning and apply features.
// See Fullwidth Punctuation Collapsing:
// https://drafts.csswg.org/css-text-4/#fullwidth-collapsing
void HanKerning::Compute(const String& text,
                         wtf_size_t start,
                         wtf_size_t end,
                         const SimpleFontData& font,
                         const FontDescription& font_description,
                         Options options,
                         FontFeatures* features) { … }

HanKerning::FontData::FontData(const SimpleFontData& font,
                               const LayoutLocale& locale,
                               bool is_horizontal) { … }

}  // namespace blink