Fix links in inline continuations in printed PDF

third_party/WebKit/Source/core/paint/BlockPainter.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 "core/paint/BlockPainter.h"
 
 #include "core/editing/DragCaretController.h"
 #include "core/editing/FrameSelection.h"
 #include "core/frame/Settings.h"
 #include "core/layout/LayoutBlockFlow.h"
@@ skipping 133 matching lines @@
     if (paintPhase == PaintPhaseMask && m_layoutBlock.style()->visibility() == VISIBLE) {
         m_layoutBlock.paintMask(paintInfo, paintOffset);
         return;
     }
 
     if (paintPhase == PaintPhaseClippingMask && m_layoutBlock.style()->visibility() == VISIBLE) {
         BoxPainter(m_layoutBlock).paintClippingMask(paintInfo, paintOffset);
         return;
     }
 
-    // FIXME: When Skia supports annotation rect covering (https://code.google.com/p/skia/issues/detail?id=3872),
-    // this rect may be covered by foreground and descendant drawings. Then we may need a dedicated paint phase.
     if (paintPhase == PaintPhaseForeground && paintInfo.isPrinting())
         ObjectPainter(m_layoutBlock).addPDFURLRectIfNeeded(paintInfo, paintOffset);
 
     {
         Optional<ScrollRecorder> scrollRecorder;
         Optional<PaintInfo> scrolledPaintInfo;
         if (m_layoutBlock.hasOverflowClip()) {
             IntSize scrollOffset = m_layoutBlock.scrolledContentOffset();
             if (m_layoutBlock.layer()->scrollsOverflow() || !scrollOffset.isZero()) {
                 scrollRecorder.emplace(paintInfo.context, m_layoutBlock, paintPhase, scrollOffset);
@@ skipping 40 matching lines @@
     if (m_layoutBlock.hasCursorCaret())
         frame->selection().paintCaret(paintInfo.context, paintOffset);
 
     if (m_layoutBlock.hasDragCaret())
         frame->page()->dragCaretController().paintDragCaret(frame, paintInfo.context, paintOffset);
 }
 
 bool BlockPainter::intersectsPaintRect(const PaintInfo& paintInfo, const LayoutPoint& paintOffset) const
 {
     LayoutRect overflowRect = m_layoutBlock.visualOverflowRect();
+
+    if (paintInfo.isPrinting() && m_layoutBlock.isAnonymousBlock() && m_layoutBlock.childrenInline()) {

[chrishtr, 2016/01/15 18:16:35]

How about:

if (paintInfo.isPrinting())
  return true;

Micro-performance of printing is not important.

I'm also not so convinced this fix is general enough. Also, can you point me
to the code that outputs these clickable rects?

[Xianzhu, 2016/01/15 18:36:29]

During printing, we paint each page separately
(https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit...),
so without this check we'll paint everything for each page. (However, it seems
we have a bug that we do paint everything for each page. Not very sure.
Verifying.)
https://code.google.com/p/chromium/codesearch#chromium/src/third_party/WebKit...

+        // For case <a href="..."><div>...</div></a>, when m_layoutBlock is the anonymous container
+        // of <a>, the anonymous container's visual overflow is empty, but we need to continue
+        // painting to output <a>'s PDF URL rect which covers the continuations, as if we included
+        // <a>'s PDF URL rect into m_layoutBlock's visual overflow. For simplicity, we just check
+        // if the parent block intersects paint rect.
+        return BlockPainter(toLayoutBlock(*m_layoutBlock.parent())).intersectsPaintRect(paintInfo, paintOffset);

[Xianzhu, 2016/01/19 20:25:33]

Now call m_layoutBlock.addElementVisualOverflowRects() instead of delegating to
parent.

+    }
+
     if (m_layoutBlock.hasOverflowModel() && m_layoutBlock.usesCompositedScrolling()) {
         overflowRect.unite(m_layoutBlock.layoutOverflowRect());
         overflowRect.move(-m_layoutBlock.scrolledContentOffset());
     }
     m_layoutBlock.flipForWritingMode(overflowRect);
     overflowRect.moveBy(paintOffset + m_layoutBlock.location());
     return paintInfo.cullRect().intersectsCullRect(overflowRect);
 }
 
 void BlockPainter::paintContents(const PaintInfo& paintInfo, const LayoutPoint& paintOffset)
@@ skipping 15 matching lines @@
 
         // We don't paint our own background, but we do let the kids paint their backgrounds.
         PaintInfo paintInfoForChild(paintInfo);
         paintInfoForChild.phase = newPhase;
         paintInfoForChild.updatePaintingRootForChildren(&m_layoutBlock);
         m_layoutBlock.paintChildren(paintInfoForChild, paintOffset);
     }
 }
 
 } // namespace blink