chromium/third_party/blink/renderer/core/layout/svg/svg_text_layout_algorithm.cc

// Copyright 2021 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/core/layout/svg/svg_text_layout_algorithm.h"

#include <algorithm>

#include "base/containers/contains.h"
#include "base/ranges/algorithm.h"
#include "base/trace_event/trace_event.h"
#include "third_party/blink/renderer/core/layout/svg/layout_svg_inline_text.h"
#include "third_party/blink/renderer/core/layout/svg/layout_svg_text_path.h"
#include "third_party/blink/renderer/core/layout/svg/resolved_text_layout_attributes_iterator.h"
#include "third_party/blink/renderer/core/layout/svg/svg_inline_node_data.h"
#include "third_party/blink/renderer/core/svg/svg_animated_length.h"
#include "third_party/blink/renderer/core/svg/svg_length_context.h"
#include "third_party/blink/renderer/core/svg/svg_text_content_element.h"
#include "third_party/blink/renderer/platform/wtf/text/code_point_iterator.h"
#include "third_party/blink/renderer/platform/wtf/wtf_size_t.h"
#include "ui/gfx/geometry/rect_conversions.h"

namespace blink {

// See https://svgwg.org/svg2-draft/text.html#TextLayoutAlgorithm

SvgTextLayoutAlgorithm::SvgTextLayoutAlgorithm(InlineNode node,
                                               WritingMode writing_mode)
    : … { … }

PhysicalSize SvgTextLayoutAlgorithm::Layout(
    const String& ifc_text_content,
    FragmentItemsBuilder::ItemWithOffsetList& items) { … }

bool SvgTextLayoutAlgorithm::Setup(wtf_size_t approximate_count) { … }

// This function updates |result_|.
void SvgTextLayoutAlgorithm::SetFlags(
    const String& ifc_text_content,
    const FragmentItemsBuilder::ItemWithOffsetList& items) { … }

void SvgTextLayoutAlgorithm::AdjustPositionsDxDy(
    const FragmentItemsBuilder::ItemWithOffsetList& items) { … }

void SvgTextLayoutAlgorithm::ApplyTextLengthAttribute(
    const FragmentItemsBuilder::ItemWithOffsetList& items) { … }

// The implementation of step 2 of "Procedure: resolve text length"
// in "5. Apply 'textLength' attribute".
//
// This function is called for elements with textLength in the order of
// closed tags. e.g.
//     <text textLength="...">
//       <tspan textLength="...">...</tspan>
//       <tspan textLength="...">...</tspan>
//     </text>
//    1. Called for the first <tspan>.
//    2. Called for the second <tspan>.
//    3. Called for the <text>.
void SvgTextLayoutAlgorithm::ResolveTextLength(
    const FragmentItemsBuilder::ItemWithOffsetList& items,
    const SvgTextContentRange& range,
    Vector<wtf_size_t>& resolved_descendant_node_starts) { … }

void SvgTextLayoutAlgorithm::AdjustPositionsXY(
    const FragmentItemsBuilder::ItemWithOffsetList& items) { … }

void SvgTextLayoutAlgorithm::ApplyAnchoring(
    const FragmentItemsBuilder::ItemWithOffsetList& items) { … }

void SvgTextLayoutAlgorithm::PositionOnPath(
    const FragmentItemsBuilder::ItemWithOffsetList& items) { … }

PhysicalSize SvgTextLayoutAlgorithm::WriteBackToFragmentItems(
    FragmentItemsBuilder::ItemWithOffsetList& items) { … }

float SvgTextLayoutAlgorithm::ScalingFactorAt(
    const FragmentItemsBuilder::ItemWithOffsetList& items,
    wtf_size_t addressable_index) const { … }

bool SvgTextLayoutAlgorithm::IsFirstCharacterInTextPath(
    wtf_size_t index) const { … }

}  // namespace blink