diff --git a/src/nodeitem.cpp b/src/nodeitem.cpp
new file mode 100644
--- /dev/null
+++ b/src/nodeitem.cpp
@@ -0,0 +1,133 @@
+/*
+ *
+ *  This file is part of the Virtual Leaf.
+ *
+ *  The Virtual Leaf is free software: you can redistribute it and/or modify
+ *  it under the terms of the GNU General Public License as published by
+ *  the Free Software Foundation, either version 3 of the License, or
+ *  (at your option) any later version.
+ *
+ *  The Virtual Leaf is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *  GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License
+ *  along with the Virtual Leaf.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *  Copyright 2010 Roeland Merks.
+ *
+ */
+
+#include <string>
+#include <QGraphicsScene>
+#include <QGraphicsItem>
+#include <QPainter>
+#include <QStyleOption>
+#include <Qt>
+#include "nodeitem.h"
+#include "parameter.h"
+
+static const std::string _module_id("$Id$");
+
+extern Parameter par;
+
+NodeItem::NodeItem( Node *n, QGraphicsScene *canvas )
+  : QGraphicsItem( 0, canvas ), SimItemBase( n, canvas) {
+  
+  brush = Qt::darkGray;
+  
+  const double mag = par.node_mag;
+  ellipsesize=QRectF(-1*mag, -1*mag, 2*mag, 2*mag);
+
+}
+
+void NodeItem::userMove(double dx, double dy) {
+  QGraphicsItem::moveBy( dx, dy );
+  
+  class_cast<Node *>(obj)->x += (dx/Cell::Magnification());
+  class_cast<Node *>(obj)->y += (dy/Cell::Magnification());
+}
+
+
+
+void NodeItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *)
+{
+
+  // from Qt4.2 example: "elastic nodes"
+  //painter->setPen(Qt::NoPen);
+  //painter->setBrush(Qt::darkGray);
+  //painter->drawEllipse(-70, -70, 200, 200);
+  
+  /* QRadialGradient gradient(-30, -30, 100);
+     
+  if (option->state & QStyle::State_Sunken) {
+  gradient.setCenter(30, 30);
+  gradient.setFocalPoint(30, 30);
+  gradient.setColorAt(1, QColor(Qt::yellow).light(120));
+  gradient.setColorAt(0, QColor(Qt::darkYellow).light(120));
+  } else {
+  gradient.setColorAt(0, Qt::yellow);
+  gradient.setColorAt(1, Qt::darkYellow);
+  }
+  
+  painter->setBrush(gradient); */
+  
+  painter->setBrush(brush);
+  painter->setPen(Qt::NoPen);
+  // const static double mag=20.;
+  painter->drawEllipse(ellipsesize);
+}
+
+
+QPainterPath NodeItem::shape() const
+{
+    QPainterPath path;
+    path.addEllipse(ellipsesize);
+    return path;
+}
+
+QRectF NodeItem::boundingRect() const
+{
+  qreal penwidth = 0;// painter->pen()->widthF();
+  return QRectF(ellipsesize.x()-penwidth/2.,ellipsesize.y()-penwidth/2.,
+		ellipsesize.width()+penwidth, ellipsesize.height()+penwidth);
+}
+
+// polymorphic OnClick functions
+void NodeItem::OnClick(void) {
+  Node *n = &getNode();
+  n->toggleBoundary();
+  setColor();
+  update();
+}
+
+void NodeItem::OnClick(const Qt::MouseButton &mb) {
+  if (mb == Qt::LeftButton) {
+    Node *n = &getNode();
+    n->toggleBoundary();
+    setColor();
+    update();
+
+  }
+}
+
+void NodeItem::setColor(void) {
+
+  static QColor indian_red("IndianRed");
+  static QColor deep_sky_blue("DeepSkyBlue");
+  static QColor purple("Purple");
+  
+  Node &n=getNode();
+
+  if (n.SamP()) {
+    setBrush( purple );
+  } else {
+    if (n.BoundaryP()) {
+      setBrush( deep_sky_blue );
+    } 
+    else {
+      setBrush( indian_red );
+    }
+  }
+}