| // Copyright 2016 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #include "core/layout/ng/inline/ng_inline_node.h" |
| |
| #include "core/layout/BidiRun.h" |
| #include "core/layout/LayoutBlockFlow.h" |
| #include "core/layout/LayoutObject.h" |
| #include "core/layout/LayoutText.h" |
| #include "core/layout/line/LineInfo.h" |
| #include "core/layout/line/RootInlineBox.h" |
| #include "core/layout/ng/inline/ng_bidi_paragraph.h" |
| #include "core/layout/ng/inline/ng_inline_break_token.h" |
| #include "core/layout/ng/inline/ng_inline_item.h" |
| #include "core/layout/ng/inline/ng_inline_items_builder.h" |
| #include "core/layout/ng/inline/ng_inline_layout_algorithm.h" |
| #include "core/layout/ng/inline/ng_line_box_fragment.h" |
| #include "core/layout/ng/inline/ng_line_breaker.h" |
| #include "core/layout/ng/inline/ng_physical_line_box_fragment.h" |
| #include "core/layout/ng/inline/ng_physical_text_fragment.h" |
| #include "core/layout/ng/inline/ng_text_fragment.h" |
| #include "core/layout/ng/layout_ng_block_flow.h" |
| #include "core/layout/ng/ng_box_fragment.h" |
| #include "core/layout/ng/ng_constraint_space_builder.h" |
| #include "core/layout/ng/ng_fragment_builder.h" |
| #include "core/layout/ng/ng_layout_result.h" |
| #include "core/layout/ng/ng_physical_box_fragment.h" |
| #include "core/style/ComputedStyle.h" |
| #include "platform/fonts/shaping/HarfBuzzShaper.h" |
| #include "platform/fonts/shaping/ShapeResultSpacing.h" |
| #include "platform/wtf/text/CharacterNames.h" |
| |
| namespace blink { |
| |
| namespace { |
| |
| struct FragmentPosition { |
| NGLogicalOffset offset; |
| LayoutUnit inline_size; |
| NGBorderEdges border_edges; |
| }; |
| |
| // Create BidiRuns from a list of NGPhysicalFragment. |
| // Produce a FragmentPosition map to place InlineBoxes. |
| void CreateBidiRuns(BidiRunList<BidiRun>* bidi_runs, |
| const Vector<RefPtr<NGPhysicalFragment>>& children, |
| const NGConstraintSpace& constraint_space, |
| NGLogicalOffset parent_offset, |
| const Vector<NGInlineItem>& items, |
| const Vector<unsigned, 32>& text_offsets, |
| Vector<FragmentPosition, 32>* positions_for_bidi_runs_out, |
| HashMap<LineLayoutItem, FragmentPosition>* positions_out) { |
| for (const auto& child : children) { |
| if (child->Type() == NGPhysicalFragment::kFragmentText) { |
| const auto* physical_fragment = ToNGPhysicalTextFragment(child.Get()); |
| const NGInlineItem& item = items[physical_fragment->ItemIndex()]; |
| BidiRun* run; |
| if (item.Type() == NGInlineItem::kText || |
| item.Type() == NGInlineItem::kControl) { |
| LayoutObject* layout_object = item.GetLayoutObject(); |
| DCHECK(layout_object->IsText()); |
| unsigned text_offset = text_offsets[physical_fragment->ItemIndex()]; |
| run = new BidiRun(physical_fragment->StartOffset() - text_offset, |
| physical_fragment->EndOffset() - text_offset, |
| item.BidiLevel(), LineLayoutItem(layout_object)); |
| layout_object->ClearNeedsLayout(); |
| } else if (item.Type() == NGInlineItem::kAtomicInline) { |
| LayoutObject* layout_object = item.GetLayoutObject(); |
| DCHECK(layout_object->IsAtomicInlineLevel()); |
| run = |
| new BidiRun(0, 1, item.BidiLevel(), LineLayoutItem(layout_object)); |
| } else { |
| continue; |
| } |
| bidi_runs->AddRun(run); |
| NGTextFragment fragment(constraint_space.WritingMode(), |
| physical_fragment); |
| // Store text fragments in a vector in the same order as BidiRunList. |
| // One LayoutText may produce multiple text fragments that they can't |
| // be set to a map. |
| positions_for_bidi_runs_out->push_back(FragmentPosition{ |
| fragment.Offset() + parent_offset, fragment.InlineSize()}); |
| } else { |
| DCHECK_EQ(child->Type(), NGPhysicalFragment::kFragmentBox); |
| NGPhysicalBoxFragment* physical_fragment = |
| ToNGPhysicalBoxFragment(child.Get()); |
| NGBoxFragment fragment(constraint_space.WritingMode(), physical_fragment); |
| NGLogicalOffset child_offset = fragment.Offset() + parent_offset; |
| if (physical_fragment->Children().size()) { |
| CreateBidiRuns(bidi_runs, physical_fragment->Children(), |
| constraint_space, child_offset, items, text_offsets, |
| positions_for_bidi_runs_out, positions_out); |
| } else { |
| // An empty inline needs a BidiRun for itself. |
| LayoutObject* layout_object = physical_fragment->GetLayoutObject(); |
| BidiRun* run = new BidiRun(0, 1, 0, LineLayoutItem(layout_object)); |
| bidi_runs->AddRun(run); |
| } |
| // Store box fragments in a map by LineLayoutItem. |
| positions_out->Set(LineLayoutItem(child->GetLayoutObject()), |
| FragmentPosition{child_offset, fragment.InlineSize(), |
| fragment.BorderEdges()}); |
| } |
| } |
| } |
| |
| // Set the geometry to InlineBoxes by using the FragmentPosition map. |
| // When the map doesn't provide positions; i.e., when InlineFlowBox doesn't have |
| // corresponding box fragment, compute the union of children. |
| unsigned PlaceInlineBoxChildren( |
| InlineFlowBox* parent, |
| const Vector<FragmentPosition, 32>& positions_for_bidi_runs, |
| const HashMap<LineLayoutItem, FragmentPosition>& positions, |
| unsigned text_index = 0, |
| bool set_parent_position_from_children = false) { |
| LayoutUnit logical_left = LayoutUnit::Max(); |
| LayoutUnit logical_right = LayoutUnit::Min(); |
| LayoutUnit logical_top = LayoutUnit::Max(); |
| for (InlineBox* inline_box = parent->FirstChild(); inline_box; |
| inline_box = inline_box->NextOnLine()) { |
| if (inline_box->IsInlineFlowBox()) { |
| InlineFlowBox* flow_box = ToInlineFlowBox(inline_box); |
| const auto& iter = positions.find(inline_box->GetLineLayoutItem()); |
| if (iter != positions.end()) { |
| const FragmentPosition& position = iter->value; |
| inline_box->SetLogicalLeft(position.offset.inline_offset); |
| inline_box->SetLogicalTop(position.offset.block_offset); |
| inline_box->SetLogicalWidth(position.inline_size); |
| flow_box->SetEdges(position.border_edges.line_left, |
| position.border_edges.line_right); |
| } |
| |
| text_index = |
| PlaceInlineBoxChildren(flow_box, positions_for_bidi_runs, positions, |
| text_index, iter == positions.end()); |
| } else { |
| const FragmentPosition& position = positions_for_bidi_runs[text_index++]; |
| inline_box->SetLogicalLeft(position.offset.inline_offset); |
| inline_box->SetLogicalTop(position.offset.block_offset); |
| inline_box->SetLogicalWidth(position.inline_size); |
| if (inline_box->GetLineLayoutItem().IsBox()) { |
| LineLayoutBox box(inline_box->GetLineLayoutItem()); |
| box.SetLocation(inline_box->Location()); |
| } |
| } |
| |
| if (set_parent_position_from_children) { |
| logical_left = std::min(inline_box->LogicalLeft(), logical_left); |
| logical_right = std::max(inline_box->LogicalRight(), logical_right); |
| logical_top = std::min(inline_box->LogicalTop(), logical_top); |
| } |
| } |
| |
| if (set_parent_position_from_children && logical_left != LayoutUnit::Max()) { |
| logical_left -= parent->MarginBorderPaddingLogicalLeft(); |
| logical_right += parent->MarginBorderPaddingLogicalRight(); |
| parent->SetLogicalLeft(logical_left); |
| parent->SetLogicalWidth(logical_right - logical_left); |
| parent->SetLogicalTop(logical_top); |
| } |
| |
| return text_index; |
| } |
| |
| } // namespace |
| |
| NGInlineNode::NGInlineNode(LayoutNGBlockFlow* block, LayoutObject* start_inline) |
| : NGLayoutInputNode(block) { |
| DCHECK(start_inline); |
| DCHECK(block); |
| block->SetLayoutNGInline(true); |
| if (!block->HasNGInlineNodeData()) { |
| block->ResetNGInlineNodeData(); |
| } |
| MutableData().start_inline_ = start_inline; |
| } |
| |
| NGInlineItemRange NGInlineNode::Items(unsigned start, unsigned end) { |
| return NGInlineItemRange(&MutableData().items_, start, end); |
| } |
| |
| void NGInlineNode::InvalidatePrepareLayout() { |
| LayoutObject* start_inline = Data().start_inline_; |
| ToLayoutNGBlockFlow(GetLayoutBlockFlow())->ResetNGInlineNodeData(); |
| MutableData().start_inline_ = start_inline; |
| MutableData().text_content_ = String(); |
| MutableData().items_.clear(); |
| } |
| |
| void NGInlineNode::PrepareLayout() { |
| // Scan list of siblings collecting all in-flow non-atomic inlines. A single |
| // NGInlineNode represent a collection of adjacent non-atomic inlines. |
| CollectInlines(Data().start_inline_, GetLayoutBlockFlow()); |
| if (Data().is_bidi_enabled_) |
| SegmentText(); |
| ShapeText(); |
| } |
| |
| // Depth-first-scan of all LayoutInline and LayoutText nodes that make up this |
| // NGInlineNode object. Collects LayoutText items, merging them up into the |
| // parent LayoutInline where possible, and joining all text content in a single |
| // string to allow bidi resolution and shaping of the entire block. |
| void NGInlineNode::CollectInlines(LayoutObject* start, LayoutBlockFlow* block) { |
| DCHECK(Data().text_content_.IsNull()); |
| DCHECK(Data().items_.IsEmpty()); |
| NGInlineItemsBuilder builder(&MutableData().items_); |
| builder.EnterBlock(block->Style()); |
| LayoutObject* next_sibling = CollectInlines(start, block, &builder); |
| builder.ExitBlock(); |
| |
| MutableData().text_content_ = builder.ToString(); |
| DCHECK(!next_sibling || !next_sibling->IsInline()); |
| MutableData().next_sibling_ = ToLayoutBox(next_sibling); |
| MutableData().is_bidi_enabled_ = |
| !Data().text_content_.IsEmpty() && |
| !(Data().text_content_.Is8Bit() && !builder.HasBidiControls()); |
| } |
| |
| LayoutObject* NGInlineNode::CollectInlines(LayoutObject* start, |
| LayoutBlockFlow* block, |
| NGInlineItemsBuilder* builder) { |
| LayoutObject* node = start; |
| while (node) { |
| if (node->IsText()) { |
| builder->SetIsSVGText(node->IsSVGInlineText()); |
| builder->Append(ToLayoutText(node)->GetText(), node->Style(), node); |
| node->ClearNeedsLayout(); |
| |
| } else if (node->IsFloating()) { |
| // Add floats and positioned objects in the same way as atomic inlines. |
| // Because these objects need positions, they will be handled in |
| // NGInlineLayoutAlgorithm. |
| builder->Append(NGInlineItem::kFloating, kObjectReplacementCharacter, |
| nullptr, node); |
| |
| } else if (node->IsOutOfFlowPositioned()) { |
| builder->Append(NGInlineItem::kOutOfFlowPositioned, |
| kObjectReplacementCharacter, nullptr, node); |
| |
| } else if (node->IsAtomicInlineLevel()) { |
| // For atomic inlines add a unicode "object replacement character" to |
| // signal the presence of a non-text object to the unicode bidi algorithm. |
| builder->Append(NGInlineItem::kAtomicInline, kObjectReplacementCharacter, |
| node->Style(), node); |
| |
| } else if (!node->IsInline()) { |
| // A block box found. End inline and transit to block layout. |
| return node; |
| |
| } else { |
| builder->EnterInline(node); |
| |
| // Traverse to children if they exist. |
| if (LayoutObject* child = node->SlowFirstChild()) { |
| node = child; |
| continue; |
| |
| } else { |
| // An empty inline node. |
| node->ClearNeedsLayout(); |
| } |
| |
| builder->ExitInline(node); |
| } |
| |
| // Find the next sibling, or parent, until we reach |block|. |
| while (true) { |
| if (LayoutObject* next = node->NextSibling()) { |
| node = next; |
| break; |
| } |
| node = node->Parent(); |
| if (node == block) |
| return nullptr; |
| DCHECK(node->IsInline()); |
| builder->ExitInline(node); |
| node->ClearNeedsLayout(); |
| } |
| } |
| return nullptr; |
| } |
| |
| void NGInlineNode::SegmentText() { |
| // TODO(kojii): Move this to caller, this will be used again after line break. |
| NGBidiParagraph bidi; |
| MutableData().text_content_.Ensure16Bit(); |
| if (!bidi.SetParagraph(Data().text_content_, Style())) { |
| // On failure, give up bidi resolving and reordering. |
| MutableData().is_bidi_enabled_ = false; |
| return; |
| } |
| if (bidi.Direction() == UBIDI_LTR) { |
| // All runs are LTR, no need to reorder. |
| MutableData().is_bidi_enabled_ = false; |
| return; |
| } |
| |
| Vector<NGInlineItem>& items = MutableData().items_; |
| unsigned item_index = 0; |
| for (unsigned start = 0; start < Data().text_content_.length();) { |
| UBiDiLevel level; |
| unsigned end = bidi.GetLogicalRun(start, &level); |
| DCHECK_EQ(items[item_index].start_offset_, start); |
| item_index = NGInlineItem::SetBidiLevel(items, item_index, end, level); |
| start = end; |
| } |
| DCHECK_EQ(item_index, items.size()); |
| } |
| |
| void NGInlineNode::ShapeText() { |
| // TODO(eae): Add support for shaping latin-1 text? |
| MutableData().text_content_.Ensure16Bit(); |
| const String& text_content = Data().text_content_; |
| |
| // Shape each item with the full context of the entire node. |
| HarfBuzzShaper shaper(text_content.Characters16(), text_content.length()); |
| ShapeResultSpacing<StringView> spacing(text_content); |
| for (auto& item : MutableData().items_) { |
| if (item.Type() != NGInlineItem::kText) |
| continue; |
| |
| const Font& font = item.Style()->GetFont(); |
| RefPtr<ShapeResult> shape_result = shaper.Shape( |
| &font, item.Direction(), item.StartOffset(), item.EndOffset()); |
| |
| if (UNLIKELY(spacing.SetSpacing(font.GetFontDescription()))) |
| shape_result->ApplySpacing(spacing, text_content, item.Direction()); |
| |
| item.shape_result_ = std::move(shape_result); |
| } |
| } |
| |
| RefPtr<NGLayoutResult> NGInlineNode::Layout(NGConstraintSpace* constraint_space, |
| NGBreakToken* break_token) { |
| // TODO(kojii): Invalidate PrepareLayout() more efficiently. |
| InvalidatePrepareLayout(); |
| PrepareLayout(); |
| |
| NGInlineLayoutAlgorithm algorithm(*this, constraint_space, |
| ToNGInlineBreakToken(break_token)); |
| RefPtr<NGLayoutResult> result = algorithm.Layout(); |
| CopyFragmentDataToLayoutBox(*constraint_space, result.Get()); |
| return result; |
| } |
| |
| enum class ContentSizeMode { Max, Sum }; |
| |
| static LayoutUnit ComputeContentSize(NGInlineNode node, |
| ContentSizeMode mode, |
| LayoutUnit available_inline_size) { |
| const ComputedStyle& style = node.Style(); |
| NGWritingMode writing_mode = FromPlatformWritingMode(style.GetWritingMode()); |
| |
| RefPtr<NGConstraintSpace> space = |
| NGConstraintSpaceBuilder(writing_mode) |
| .SetTextDirection(style.Direction()) |
| .SetAvailableSize({available_inline_size, NGSizeIndefinite}) |
| .ToConstraintSpace(writing_mode); |
| |
| NGFragmentBuilder container_builder( |
| NGPhysicalFragment::NGFragmentType::kFragmentBox, node); |
| |
| NGLineBreaker line_breaker(node, space.Get(), &container_builder); |
| NGLineInfo line_info; |
| LayoutUnit result; |
| while (line_breaker.NextLine(&line_info, NGLogicalOffset())) { |
| LayoutUnit inline_size; |
| for (const NGInlineItemResult item_result : line_info.Results()) |
| inline_size += item_result.inline_size; |
| if (mode == ContentSizeMode::Max) { |
| result = std::max(inline_size, result); |
| } else { |
| result += inline_size; |
| } |
| } |
| return result; |
| } |
| |
| MinMaxContentSize NGInlineNode::ComputeMinMaxContentSize() { |
| // TODO(kojii): Invalidate PrepareLayout() more efficiently. |
| InvalidatePrepareLayout(); |
| PrepareLayout(); |
| |
| // Run line breaking with 0 and indefinite available width. |
| |
| // TODO(kojii): There are several ways to make this more efficient and faster |
| // than runnning two line breaking. |
| |
| // Compute the max of inline sizes of all line boxes with 0 available inline |
| // size. This gives the min-content, the width where lines wrap at every |
| // break opportunity. |
| MinMaxContentSize sizes; |
| sizes.min_content = |
| ComputeContentSize(*this, ContentSizeMode::Max, LayoutUnit()); |
| |
| // Compute the sum of inline sizes of all inline boxes with no line breaks. |
| // TODO(kojii): NGConstraintSpaceBuilder does not allow NGSizeIndefinite |
| // inline available size. We can allow it, or make this more efficient |
| // without using NGLineBreaker. |
| sizes.max_content = |
| ComputeContentSize(*this, ContentSizeMode::Sum, LayoutUnit::Max()); |
| |
| return sizes; |
| } |
| |
| NGLayoutInputNode NGInlineNode::NextSibling() { |
| // TODO(kojii): Invalidate PrepareLayout() more efficiently. |
| InvalidatePrepareLayout(); |
| PrepareLayout(); |
| return NGBlockNode(Data().next_sibling_); |
| } |
| |
| void NGInlineNode::CopyFragmentDataToLayoutBox( |
| const NGConstraintSpace& constraint_space, |
| NGLayoutResult* layout_result) { |
| LayoutBlockFlow* block_flow = GetLayoutBlockFlow(); |
| block_flow->DeleteLineBoxTree(); |
| |
| const Vector<NGInlineItem>& items = Data().items_; |
| Vector<unsigned, 32> text_offsets(items.size()); |
| GetLayoutTextOffsets(&text_offsets); |
| |
| FontBaseline baseline_type = |
| IsHorizontalWritingMode(constraint_space.WritingMode()) |
| ? FontBaseline::kAlphabeticBaseline |
| : FontBaseline::kIdeographicBaseline; |
| |
| Vector<FragmentPosition, 32> positions_for_bidi_runs; |
| HashMap<LineLayoutItem, FragmentPosition> positions; |
| BidiRunList<BidiRun> bidi_runs; |
| LineInfo line_info; |
| NGPhysicalBoxFragment* box_fragment = |
| ToNGPhysicalBoxFragment(layout_result->PhysicalFragment().Get()); |
| for (const auto& container_child : box_fragment->Children()) { |
| NGPhysicalLineBoxFragment* physical_line_box = |
| ToNGPhysicalLineBoxFragment(container_child.Get()); |
| NGLineBoxFragment line_box(constraint_space.WritingMode(), |
| physical_line_box); |
| |
| // Create a BidiRunList for this line. |
| CreateBidiRuns(&bidi_runs, physical_line_box->Children(), constraint_space, |
| {line_box.InlineOffset(), LayoutUnit(0)}, items, |
| text_offsets, &positions_for_bidi_runs, &positions); |
| // TODO(kojii): bidi needs to find the logical last run. |
| bidi_runs.SetLogicallyLastRun(bidi_runs.LastRun()); |
| |
| // Create a RootInlineBox from BidiRunList. InlineBoxes created for the |
| // RootInlineBox are set to Bidirun::m_box. |
| line_info.SetEmpty(false); |
| // TODO(kojii): Implement setFirstLine, LastLine, etc. |
| RootInlineBox* root_line_box = |
| block_flow->ConstructLine(bidi_runs, line_info); |
| |
| // Copy fragments data to InlineBoxes. |
| PlaceInlineBoxChildren(root_line_box, positions_for_bidi_runs, positions); |
| |
| // Copy to RootInlineBox. |
| root_line_box->SetLogicalLeft(line_box.InlineOffset()); |
| root_line_box->SetLogicalWidth(line_box.InlineSize()); |
| LayoutUnit line_top = line_box.BlockOffset(); |
| NGLineHeightMetrics line_metrics(Style(), baseline_type); |
| const NGLineHeightMetrics& max_with_leading = physical_line_box->Metrics(); |
| LayoutUnit baseline = line_top + max_with_leading.ascent; |
| root_line_box->SetLogicalTop(baseline - line_metrics.ascent); |
| root_line_box->SetLineTopBottomPositions( |
| baseline - line_metrics.ascent, baseline + line_metrics.descent, |
| line_top, baseline + max_with_leading.descent); |
| |
| bidi_runs.DeleteRuns(); |
| positions_for_bidi_runs.clear(); |
| positions.clear(); |
| } |
| } |
| |
| // Compute the delta of text offsets between NGInlineNode and LayoutText. |
| // This map is needed to produce InlineTextBox since its offsets are to |
| // LayoutText. |
| // TODO(kojii): Since NGInlineNode has text after whitespace collapsed, the |
| // length may not match with LayoutText. This function updates LayoutText to |
| // match, but this needs more careful coding, if we keep copying to layoutobject |
| // tree. |
| void NGInlineNode::GetLayoutTextOffsets( |
| Vector<unsigned, 32>* text_offsets_out) { |
| LayoutText* current_text = nullptr; |
| unsigned current_offset = 0; |
| const Vector<NGInlineItem>& items = Data().items_; |
| |
| for (unsigned i = 0; i < items.size(); i++) { |
| const NGInlineItem& item = items[i]; |
| LayoutObject* next_object = item.GetLayoutObject(); |
| LayoutText* next_text = next_object && next_object->IsText() |
| ? ToLayoutText(next_object) |
| : nullptr; |
| if (next_text != current_text) { |
| if (current_text && |
| current_text->TextLength() != item.StartOffset() - current_offset) { |
| current_text->SetTextInternal( |
| Text(current_offset, item.StartOffset()).ToString().Impl()); |
| } |
| current_text = next_text; |
| current_offset = item.StartOffset(); |
| } |
| (*text_offsets_out)[i] = current_offset; |
| } |
| if (current_text && current_text->TextLength() != |
| Data().text_content_.length() - current_offset) { |
| current_text->SetTextInternal( |
| Text(current_offset, Data().text_content_.length()).ToString().Impl()); |
| } |
| } |
| |
| void NGInlineNode::CheckConsistency() const { |
| #if DCHECK_IS_ON() |
| const Vector<NGInlineItem>& items = Data().items_; |
| for (const NGInlineItem& item : items) { |
| DCHECK(!item.GetLayoutObject() || !item.Style() || |
| item.Style() == item.GetLayoutObject()->Style()); |
| } |
| #endif |
| } |
| |
| String NGInlineNode::ToString() const { |
| return String::Format("NGInlineNode"); |
| } |
| |
| } // namespace blink |