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diff --git a/examples/widgets/graphicsview/elasticnodes/edge.cpp b/examples/widgets/graphicsview/elasticnodes/edge.cpp
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+++ b/examples/widgets/graphicsview/elasticnodes/edge.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2012 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: http://www.qt-project.org/
+**
+** This file is part of the examples of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
+**     the names of its contributors may be used to endorse or promote
+**     products derived from this software without specific prior written
+**     permission.
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QPainter>
+
+#include "edge.h"
+#include "node.h"
+
+#include <math.h>
+
+static const double Pi = 3.14159265358979323846264338327950288419717;
+static double TwoPi = 2.0 * Pi;
+
+//! [0]
+Edge::Edge(Node *sourceNode, Node *destNode)
+    : arrowSize(10)
+{
+    setAcceptedMouseButtons(0);
+    source = sourceNode;
+    dest = destNode;
+    source->addEdge(this);
+    dest->addEdge(this);
+    adjust();
+}
+//! [0]
+
+//! [1]
+Node *Edge::sourceNode() const
+{
+    return source;
+}
+
+Node *Edge::destNode() const
+{
+    return dest;
+}
+//! [1]
+
+//! [2]
+void Edge::adjust()
+{
+    if (!source || !dest)
+        return;
+
+    QLineF line(mapFromItem(source, 0, 0), mapFromItem(dest, 0, 0));
+    qreal length = line.length();
+
+    prepareGeometryChange();
+
+    if (length > qreal(20.)) {
+        QPointF edgeOffset((line.dx() * 10) / length, (line.dy() * 10) / length);
+        sourcePoint = line.p1() + edgeOffset;
+        destPoint = line.p2() - edgeOffset;
+    } else {
+        sourcePoint = destPoint = line.p1();
+    }
+}
+//! [2]
+
+//! [3]
+QRectF Edge::boundingRect() const
+{
+    if (!source || !dest)
+        return QRectF();
+
+    qreal penWidth = 1;
+    qreal extra = (penWidth + arrowSize) / 2.0;
+
+    return QRectF(sourcePoint, QSizeF(destPoint.x() - sourcePoint.x(),
+                                      destPoint.y() - sourcePoint.y()))
+        .normalized()
+        .adjusted(-extra, -extra, extra, extra);
+}
+//! [3]
+
+//! [4]
+void Edge::paint(QPainter *painter, const QStyleOptionGraphicsItem *, QWidget *)
+{
+    if (!source || !dest)
+        return;
+
+    QLineF line(sourcePoint, destPoint);
+    if (qFuzzyCompare(line.length(), qreal(0.)))
+        return;
+//! [4]
+
+//! [5]
+    // Draw the line itself
+    painter->setPen(QPen(Qt::black, 1, Qt::SolidLine, Qt::RoundCap, Qt::RoundJoin));
+    painter->drawLine(line);
+//! [5]
+
+//! [6]
+    // Draw the arrows
+    double angle = ::acos(line.dx() / line.length());
+    if (line.dy() >= 0)
+        angle = TwoPi - angle;
+
+    QPointF sourceArrowP1 = sourcePoint + QPointF(sin(angle + Pi / 3) * arrowSize,
+                                                  cos(angle + Pi / 3) * arrowSize);
+    QPointF sourceArrowP2 = sourcePoint + QPointF(sin(angle + Pi - Pi / 3) * arrowSize,
+                                                  cos(angle + Pi - Pi / 3) * arrowSize);   
+    QPointF destArrowP1 = destPoint + QPointF(sin(angle - Pi / 3) * arrowSize,
+                                              cos(angle - Pi / 3) * arrowSize);
+    QPointF destArrowP2 = destPoint + QPointF(sin(angle - Pi + Pi / 3) * arrowSize,
+                                              cos(angle - Pi + Pi / 3) * arrowSize);
+
+    painter->setBrush(Qt::black);
+    painter->drawPolygon(QPolygonF() << line.p1() << sourceArrowP1 << sourceArrowP2);
+    painter->drawPolygon(QPolygonF() << line.p2() << destArrowP1 << destArrowP2);
+}
+//! [6]