[LayoutNG] Add NGLineBoxFragment

third_party/WebKit/Source/core/layout/ng/ng_line_builder.h

 // 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 NGLineBuilder_h
 #define NGLineBuilder_h
 
 #include "core/CoreExport.h"
 #include "core/layout/ng/geometry/ng_logical_offset.h"
 #include "core/layout/ng/ng_constraint_space_builder.h"
 #include "core/layout/ng/ng_fragment_builder.h"
-#include "core/layout/ng/ng_layout_opportunity_iterator.h"
-#include "core/layout/ng/ng_physical_fragment.h"
+#include "core/layout/ng/ng_line_height_metrics.h"
 #include "platform/fonts/FontBaseline.h"
 #include "platform/heap/Handle.h"
 #include "wtf/Vector.h"
 
 namespace blink {
 
-class ComputedStyle;
-class FontMetrics;
 class NGConstraintSpace;
 class NGInlineNode;
 class NGLayoutInlineItem;
+class NGLineBoxFragmentBuilder;
+class NGTextFragmentBuilder;
 
 // NGLineBuilder creates the fragment tree for a line.
 // NGLineBuilder manages the current line as a range, |start| and |end|.
 // |end| can be extended multiple times before creating a line, usually until
 // |!CanFitOnLine()|.
 // |SetBreakOpportunity| can mark the last confirmed offset that can fit.
 class CORE_EXPORT NGLineBuilder final {
   STACK_ALLOCATED();
 
  public:
@@ skipping 78 matching lines @@
   void BidiReorder(Vector<LineItemChunk, 32>*);
 
   // Lays out the inline float.
   // List of actions:
   // - tries to position the float right away if we have enough space.
   // - updates the current_opportunity if we actually place the float.
   // - if it's too wide then we add the float to the unpositioned list so it can
   //   be positioned after we're done with the current line.
   void LayoutAndPositionFloat(LayoutUnit end_position, LayoutObject*);
 
-  // Represents block-direction metrics for an |NGLayoutInlineItem|.
-  struct InlineItemMetrics {
-    float ascent;
-    float descent;
-    float ascent_and_leading;
-    float descent_and_leading;
-
-    // Use the leading from the 'line-height' property, or the font metrics of
-    // the primary font if 'line-height: normal'.
-    InlineItemMetrics(const ComputedStyle&, FontBaseline);
-
-    // Use the leading from the font metrics.
-    InlineItemMetrics(const FontMetrics&, FontBaseline);
-
-   private:
-    void Initialize(const FontMetrics&, FontBaseline, float line_height);
-  };
-
-  // LineBoxData is a set of data for a line box that are computed in early
-  // phases, such as in |CreateLine()|, and will be used in later phases.
-  // TODO(kojii): Not sure if all these data are needed in fragment tree. If
-  // they are, we can create a linebox fragment, store them there, and this
-  // isn't needed. For now, we're trying to minimize data in fragments.
-  struct LineBoxData {
-    unsigned fragment_end;
-    LayoutUnit inline_size;
-    LayoutUnit top_with_leading;
-    float max_ascent = 0;
-    float max_descent = 0;
-    float max_ascent_and_leading = 0;
-    float max_descent_and_leading = 0;
-
-    // Include |InlineItemMetrics| into the metrics for this line box.
-    void UpdateMaxAscentAndDescent(const InlineItemMetrics&);
-  };
-
   void PlaceItems(const Vector<LineItemChunk, 32>&);
   void AccumulateUsedFonts(const NGLayoutInlineItem&,
                            const LineItemChunk&,
-                           LineBoxData*);
+                           NGLineBoxFragmentBuilder*);
   LayoutUnit PlaceAtomicInline(const NGLayoutInlineItem&,
                                LayoutUnit estimated_baseline,
-                               LineBoxData*,
-                               NGFragmentBuilder*);
+                               NGLineBoxFragmentBuilder*,
+                               NGTextFragmentBuilder*);
 
   // Finds the next layout opportunity for the next text fragment.
   void FindNextLayoutOpportunity();
 
   Persistent<NGInlineNode> inline_box_;
   NGConstraintSpace* constraint_space_;  // Not owned as STACK_ALLOCATED.
   Vector<RefPtr<NGLayoutResult>, 32> layout_results_;
-  Vector<LineBoxData, 32> line_box_data_list_;
   unsigned start_index_ = 0;
   unsigned start_offset_ = 0;
   unsigned last_index_ = 0;
   unsigned end_offset_ = 0;
   unsigned last_break_opportunity_index_ = 0;
   unsigned last_break_opportunity_offset_ = 0;
   LayoutUnit end_position_;
   LayoutUnit last_break_opportunity_position_;
   LayoutUnit content_size_;
   LayoutUnit max_inline_size_;
   NGFragmentBuilder container_builder_;
   RefPtr<NGLayoutResult> container_layout_result_;
   FontBaseline baseline_type_ = FontBaseline::AlphabeticBaseline;
 
   NGLogicalOffset bfc_offset_;
   NGLogicalRect current_opportunity_;
 
   unsigned is_horizontal_writing_mode_ : 1;
 
   NGConstraintSpaceBuilder space_builder_;
 #if DCHECK_IS_ON()
   unsigned is_bidi_reordered_ : 1;
 #endif
 };
 
 }  // namespace blink
 
 #endif  // NGLineBuilder_h