| // 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. |
| |
| #ifndef NGFragmentBuilder_h |
| #define NGFragmentBuilder_h |
| |
| #include "core/layout/ng/geometry/ng_border_edges.h" |
| #include "core/layout/ng/geometry/ng_physical_rect.h" |
| #include "core/layout/ng/inline/ng_baseline.h" |
| #include "core/layout/ng/ng_break_token.h" |
| #include "core/layout/ng/ng_container_fragment_builder.h" |
| #include "core/layout/ng/ng_layout_result.h" |
| #include "core/layout/ng/ng_out_of_flow_positioned_descendant.h" |
| #include "platform/heap/Handle.h" |
| #include "platform/wtf/Allocator.h" |
| |
| namespace blink { |
| |
| class NGPhysicalFragment; |
| |
| class CORE_EXPORT NGFragmentBuilder final : public NGContainerFragmentBuilder { |
| DISALLOW_NEW(); |
| |
| public: |
| NGFragmentBuilder(NGLayoutInputNode, |
| scoped_refptr<const ComputedStyle>, |
| NGWritingMode, |
| TextDirection); |
| |
| // Build a fragment for LayoutObject without NGLayoutInputNode. LayoutInline |
| // has NGInlineItem but does not have corresponding NGLayoutInputNode. |
| NGFragmentBuilder(LayoutObject*, |
| scoped_refptr<const ComputedStyle>, |
| NGWritingMode, |
| TextDirection); |
| |
| ~NGFragmentBuilder() override; |
| |
| using WeakBoxList = PersistentHeapLinkedHashSet<WeakMember<NGBlockNode>>; |
| |
| NGLogicalSize Size() const final { return {inline_size_, block_size_}; } |
| |
| NGFragmentBuilder& SetIntrinsicBlockSize(LayoutUnit); |
| |
| using NGContainerFragmentBuilder::AddChild; |
| |
| // Our version of AddChild captures any child NGBreakTokens. |
| NGContainerFragmentBuilder& AddChild(scoped_refptr<NGPhysicalFragment>, |
| const NGLogicalOffset&) final; |
| |
| // Add a break token for a child that doesn't yet have any fragments, because |
| // its first fragment is to be produced in the next fragmentainer. This will |
| // add a break token for the child, but no fragment. |
| NGFragmentBuilder& AddBreakBeforeChild(NGLayoutInputNode child); |
| |
| // Update if we have fragmented in this flow. |
| NGFragmentBuilder& PropagateBreak(scoped_refptr<NGLayoutResult>); |
| NGFragmentBuilder& PropagateBreak(scoped_refptr<NGPhysicalFragment>); |
| |
| // Builder has non-trivial out-of-flow descendant methods. |
| // These methods are building blocks for implementation of |
| // out-of-flow descendants by layout algorithms. |
| // |
| // They are intended to be used by layout algorithm like this: |
| // |
| // Part 1: layout algorithm positions in-flow children. |
| // out-of-flow children, and out-of-flow descendants of fragments |
| // are stored inside builder. |
| // |
| // for (child : children) |
| // if (child->position == (Absolute or Fixed)) |
| // builder->AddOutOfFlowChildCandidate(child); |
| // else |
| // fragment = child->Layout() |
| // builder->AddChild(fragment) |
| // end |
| // |
| // builder->SetSize |
| // |
| // Part 2: Out-of-flow layout part positions out-of-flow descendants. |
| // |
| // NGOutOfFlowLayoutPart(container_style, builder).Run(); |
| // |
| // See layout part for builder interaction. |
| NGFragmentBuilder& AddOutOfFlowChildCandidate(NGBlockNode, |
| const NGLogicalOffset&); |
| |
| void AddOutOfFlowLegacyCandidate(NGBlockNode, const NGStaticPosition&); |
| |
| void GetAndClearOutOfFlowDescendantCandidates( |
| Vector<NGOutOfFlowPositionedDescendant>* descendant_candidates); |
| |
| // Set how much of the block size we've used so far for this box. |
| NGFragmentBuilder& SetUsedBlockSize(LayoutUnit used_block_size) { |
| used_block_size_ = used_block_size; |
| return *this; |
| } |
| |
| // Specify that we broke. |
| // |
| // This will result in a fragment which has an unfinished break token. |
| NGFragmentBuilder& SetDidBreak() { |
| did_break_ = true; |
| return *this; |
| } |
| |
| // Offsets are not supposed to be set during fragment construction, so we |
| // do not provide a setter here. |
| |
| // Creates the fragment. Can only be called once. |
| scoped_refptr<NGLayoutResult> ToBoxFragment(); |
| |
| scoped_refptr<NGLayoutResult> Abort(NGLayoutResult::NGLayoutResultStatus); |
| |
| // A vector of child offsets. Initially set by AddChild(). |
| const Vector<NGLogicalOffset>& Offsets() const { return offsets_; } |
| Vector<NGLogicalOffset>& MutableOffsets() { return offsets_; } |
| |
| NGPhysicalFragment::NGBoxType BoxType() const; |
| NGFragmentBuilder& SetBoxType(NGPhysicalFragment::NGBoxType); |
| |
| bool DidBreak() const { return did_break_; } |
| |
| NGFragmentBuilder& SetBorderEdges(NGBorderEdges border_edges) { |
| border_edges_ = border_edges; |
| return *this; |
| } |
| |
| // Layout algorithms should call this function for each baseline request in |
| // the constraint space. |
| // |
| // If a request should use a synthesized baseline from the box rectangle, |
| // algorithms can omit the call. |
| // |
| // This function should be called at most once for a given algorithm/baseline |
| // type pair. |
| void AddBaseline(NGBaselineRequest, LayoutUnit); |
| |
| private: |
| NGLayoutInputNode node_; |
| LayoutObject* layout_object_; |
| |
| LayoutUnit intrinsic_block_size_; |
| |
| NGPhysicalFragment::NGBoxType box_type_; |
| bool did_break_; |
| LayoutUnit used_block_size_; |
| |
| Vector<scoped_refptr<NGBreakToken>> child_break_tokens_; |
| scoped_refptr<NGBreakToken> last_inline_break_token_; |
| |
| Vector<NGBaseline> baselines_; |
| |
| NGBorderEdges border_edges_; |
| }; |
| |
| } // namespace blink |
| |
| #endif // NGFragmentBuilder |