Save previous paint offset in LayoutObject

third_party/WebKit/Source/core/paint/LineBoxListPainter.cpp

 // Copyright 2014 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 "config.h"
 #include "core/paint/LineBoxListPainter.h"
 
 #include "core/layout/LayoutBoxModelObject.h"
 #include "core/layout/LayoutInline.h"
 #include "core/layout/api/LineLayoutBoxModel.h"
 #include "core/layout/line/InlineFlowBox.h"
 #include "core/layout/line/LineBoxList.h"
 #include "core/layout/line/RootInlineBox.h"
 #include "core/paint/InlinePainter.h"
 #include "core/paint/ObjectPainter.h"
 #include "core/paint/PaintInfo.h"
+#include "platform/graphics/paint/DisplayItemList.h"
 
 namespace blink {
 
 static void addPDFURLRectsForInlineChildrenRecursively(LayoutObject* layoutObject, const PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
     for (LayoutObject* child = layoutObject->slowFirstChild(); child; child = child->nextSibling()) {
         if (!child->isLayoutInline() || toLayoutBoxModelObject(child)->hasSelfPaintingLayer())
             continue;
         ObjectPainter(*child).addPDFURLRectIfNeeded(paintInfo, paintOffset);
         addPDFURLRectsForInlineChildrenRecursively(child, paintInfo, paintOffset);
@@ skipping 28 matching lines @@
     // them. Note that boxes can easily overlap, so we can't make any assumptions
     // based off positions of our first line box or our last line box.
     for (InlineFlowBox* curr = m_lineBoxList.firstLineBox(); curr; curr = curr->nextLineBox()) {
         if (m_lineBoxList.lineIntersectsDirtyRect(LineLayoutBoxModel(layoutObject), curr, info, paintOffset)) {
             RootInlineBox& root = curr->root();
             curr->paint(info, paintOffset, root.lineTop(), root.lineBottom());
         }
     }
 }
 
+static void invalidateLineBoxPaintOffsetsInternal(DisplayItemList* displayItemList, InlineFlowBox* inlineBox)
+{
+    displayItemList->invalidatePaintOffset(*inlineBox);
+    for (InlineBox* child = inlineBox->firstChild(); child; child = child->nextOnLine()) {
+        if (!child->lineLayoutItem().isText() && child->boxModelObject().hasSelfPaintingLayer())
+            continue;
+        if (child->isInlineFlowBox())
+            invalidateLineBoxPaintOffsetsInternal(displayItemList, toInlineFlowBox(child));
+        else
+            displayItemList->invalidatePaintOffset(*child);
+    }
+}
+
+void LineBoxListPainter::invalidateLineBoxPaintOffsets(const PaintInfo& paintInfo) const
+{
+    DisplayItemList* displayItemList = paintInfo.context->displayItemList();
+    for (InlineFlowBox* curr = m_lineBoxList.firstLineBox(); curr; curr = curr->nextLineBox())
+        invalidateLineBoxPaintOffsetsInternal(displayItemList, curr);
+}
+
 } // namespace blink