Paint collapsed borders of a table as one display item

third_party/WebKit/Source/core/layout/LayoutTableCell.h

 /*
  * Copyright (C) 1997 Martin Jones (mjones@kde.org)
  *           (C) 1997 Torben Weis (weis@kde.org)
  *           (C) 1998 Waldo Bastian (bastian@kde.org)
  *           (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2009, 2013 Apple Inc.
  *               All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 167 matching lines @@
 
   int borderLeft() const override;
   int borderRight() const override;
   int borderTop() const override;
   int borderBottom() const override;
   int borderStart() const override;
   int borderEnd() const override;
   int borderBefore() const override;
   int borderAfter() const override;
 
-  void collectBorderValues(LayoutTable::CollapsedBorderValues&);
-  static void sortBorderValues(LayoutTable::CollapsedBorderValues&);
+  // Returns true if any collapsed borders related to this cell changed.
+  bool collectBorderValues(Vector<CollapsedBorderValue>&);
+  static void sortBorderValues(Vector<CollapsedBorderValue>&);
 
   void layout() override;
 
   void paint(const PaintInfo&, const LayoutPoint&) const override;
 
   int cellBaselinePosition() const;
   bool isBaselineAligned() const {
     EVerticalAlign va = style()->verticalAlign();
     return va == VerticalAlignBaseline || va == VerticalAlignTextBottom ||
            va == VerticalAlignTextTop || va == VerticalAlignSuper ||
@@ skipping 82 matching lines @@
   bool isFirstOrLastCellInRow() const {
     return !table()->cellAfter(this) || !table()->cellBefore(this);
   }
 #endif
 
   const char* name() const override { return "LayoutTableCell"; }
 
   bool backgroundIsKnownToBeOpaqueInRect(const LayoutRect&) const override;
   void invalidateDisplayItemClients(PaintInvalidationReason) const override;
 
-  // TODO(wkorman): Consider renaming to more clearly differentiate from
-  // CollapsedBorderValue.
-  class CollapsedBorderValues : public DisplayItemClient {
-   public:
-    CollapsedBorderValues(const LayoutTable&,
-                          const CollapsedBorderValue& startBorder,
-                          const CollapsedBorderValue& endBorder,
-                          const CollapsedBorderValue& beforeBorder,
-                          const CollapsedBorderValue& afterBorder);
+  struct CollapsedBorderValues {
+    CollapsedBorderValue startBorder;
+    CollapsedBorderValue endBorder;
+    CollapsedBorderValue beforeBorder;
+    CollapsedBorderValue afterBorder;
 
-    const CollapsedBorderValue& startBorder() const { return m_startBorder; }
-    const CollapsedBorderValue& endBorder() const { return m_endBorder; }
-    const CollapsedBorderValue& beforeBorder() const { return m_beforeBorder; }
-    const CollapsedBorderValue& afterBorder() const { return m_afterBorder; }
-
-    void setCollapsedBorderValues(const CollapsedBorderValues& other);
-
-    // DisplayItemClient methods.
-    String debugName() const;
-    LayoutRect visualRect() const;
-
-   private:
-    const LayoutTable& m_layoutTable;
-    CollapsedBorderValue m_startBorder;
-    CollapsedBorderValue m_endBorder;
-    CollapsedBorderValue m_beforeBorder;
-    CollapsedBorderValue m_afterBorder;
+    bool allBordersAreInvisible() const {
+      return !startBorder.isVisible() && !endBorder.isVisible() &&
+             !beforeBorder.isVisible() && !afterBorder.isVisible();
+    }
+    bool bordersVisuallyEqual(const CollapsedBorderValues& other) const {
+      return startBorder.visuallyEquals(other.startBorder) &&
+             endBorder.visuallyEquals(other.endBorder) &&
+             beforeBorder.visuallyEquals(other.beforeBorder) &&
+             afterBorder.visuallyEquals(other.afterBorder);
+    }
   };
 
   class RowBackgroundDisplayItemClient : public DisplayItemClient {
    public:
     RowBackgroundDisplayItemClient(const LayoutTableCell&);
 
     // DisplayItemClient methods.
     String debugName() const;
     LayoutRect visualRect() const;
 
    private:
     const LayoutTableCell& m_layoutTableCell;
   };
 
   bool usesCompositedCellDisplayItemClients() const;
+
   const CollapsedBorderValues* collapsedBorderValues() const {
     return m_collapsedBorderValues.get();
   }
   const DisplayItemClient& backgroundDisplayItemClient() const {
     return m_rowBackgroundDisplayItemClient
                ? static_cast<const DisplayItemClient&>(
                      *m_rowBackgroundDisplayItemClient)
                : *this;
   }
 
   LayoutRect debugRect() const override;
 
   void adjustChildDebugRect(LayoutRect&) const override;
 
   // A table cell's location is relative to its containing section.
   LayoutBox* locationContainer() const override { return section(); }
 
   void ensureIsReadyForPaintInvalidation() override;
 
+  LayoutRect localVisualRect() const override;
+
  protected:
   void styleDidChange(StyleDifference, const ComputedStyle* oldStyle) override;
   void computePreferredLogicalWidths() override;
 
   void addLayerHitTestRects(LayerHitTestRects&,
                             const PaintLayer* currentCompositedLayer,
                             const LayoutPoint& layerOffset,
                             const LayoutRect& containerRect) const override;
 
  private:
   bool isOfType(LayoutObjectType type) const override {
     return type == LayoutObjectTableCell || LayoutBlockFlow::isOfType(type);
   }
 
   void willBeRemovedFromTree() override;
 
   void updateLogicalWidth() override;
 
   void paintBoxDecorationBackground(const PaintInfo&,
                                     const LayoutPoint&) const override;
   void paintMask(const PaintInfo&, const LayoutPoint&) const override;
 
   LayoutSize offsetFromContainer(const LayoutObject*) const override;
-  LayoutRect localVisualRect() const override;
 
   int borderHalfLeft(bool outer) const;
   int borderHalfRight(bool outer) const;
   int borderHalfTop(bool outer) const;
   int borderHalfBottom(bool outer) const;
 
   int borderHalfStart(bool outer) const;
   int borderHalfEnd(bool outer) const;
   int borderHalfBefore(bool outer) const;
   int borderHalfAfter(bool outer) const;
@@ skipping 17 matching lines @@
   // column, column group).
   // TODO(jchaffraix): It should be easier to compute all the borders in
   // physical coordinates. However this is not the design of the current code.
   //
   // Blink's support for mixed directionality is currently partial. We only
   // support the directionality up to |styleForCellFlow|. See comment on the
   // function above for more details.
   // See also https://code.google.com/p/chromium/issues/detail?id=128227 for
   // some history.
   //
-  // Those functions are called when the cache (m_collapsedBorders) is
-  // invalidated on LayoutTable.
+  // Those functions are called before paint invalidation if the collapsed
+  // borders cache is invalidated on LayoutTable.
   CollapsedBorderValue computeCollapsedStartBorder(
       IncludeBorderColorOrNot = IncludeBorderColor) const;
   CollapsedBorderValue computeCollapsedEndBorder(
       IncludeBorderColorOrNot = IncludeBorderColor) const;
   CollapsedBorderValue computeCollapsedBeforeBorder(
       IncludeBorderColorOrNot = IncludeBorderColor) const;
   CollapsedBorderValue computeCollapsedAfterBorder(
       IncludeBorderColorOrNot = IncludeBorderColor) const;
 
   Length logicalWidthFromColumns(LayoutTableCol* firstColForThisCell,
@@ skipping 41 matching lines @@
   return toLayoutTableCell(firstChild());
 }
 
 inline LayoutTableCell* LayoutTableRow::lastCell() const {
   return toLayoutTableCell(lastChild());
 }
 
 }  // namespace blink
 
 #endif  // LayoutTableCell_h