diff --git a/src/piechart/piepresenter.cpp b/src/piechart/piepresenter.cpp
index 286bc2c..2ebde05 100644
--- a/src/piechart/piepresenter.cpp
+++ b/src/piechart/piepresenter.cpp
@@ -14,15 +14,7 @@ PiePresenter::PiePresenter(QGraphicsItem *parent, QPieSeries *series)
     m_series(series)
 {
     Q_ASSERT(series);
-    connect(series, SIGNAL(changed(const QPieSeries::ChangeSet&)), this, SLOT(handleSeriesChanged(const QPieSeries::ChangeSet&)));
-    connect(series, SIGNAL(piePositionChanged()), this, SLOT(updateGeometry()));
-    connect(series, SIGNAL(pieSizeChanged()), this, SLOT(updateGeometry()));
-
-    if (m_series->count()) {
-        QPieSeries::ChangeSet changeSet;
-        changeSet.appendAdded(m_series->m_slices);
-        handleSeriesChanged(changeSet);
-    }
+    connect(series, SIGNAL(changed()), this, SLOT(handleSeriesChanged()));
 
     // Note: the following does not affect as long as the item does not have anything to paint
     setZValue(ChartPresenter::PieSeriesZValue);
@@ -41,43 +33,38 @@ void PiePresenter::paint(QPainter *painter, const QStyleOptionGraphicsItem *, QW
     //painter->drawRect(m_debugRect);
 }
 
-void PiePresenter::handleSeriesChanged(const QPieSeries::ChangeSet& changeSet)
+void PiePresenter::handleSeriesChanged()
 {
-    //qDebug() << "PiePresenter::handleSeriesChanged()";
-    //qDebug() << "  added  : " << changeSet.added();
-    //qDebug() << "  changed: " << changeSet.changed();
-    //qDebug() << "  removed: " << changeSet.removed();
-
-    foreach (QPieSlice* s, changeSet.added())
-        addSlice(s);
-
-    foreach (QPieSlice* s, changeSet.changed())
-        updateSlice(s);
-
-    foreach (QPieSlice* s, changeSet.removed())
-        deleteSlice(s);
+    QVector<PieSliceLayout> sliceLayout = calculateLayout();
+    applyLayout(sliceLayout);
+    update();
+}
 
-    // every change possibly changes the actual pie size
-    updateGeometry();
+void PiePresenter::handleSliceChanged()
+{
+    // TODO: optimize don't need to handle all slices
+    QVector<PieSliceLayout> sliceLayout = calculateLayout();
+    applyLayout(sliceLayout);
+    update();
 }
 
-void PiePresenter::handleDomainChanged(const Domain& domain)
+void PiePresenter::handleDomainChanged(qreal, qreal, qreal, qreal)
 {
     // TODO
 }
 
 void PiePresenter::handleGeometryChanged(const QRectF& rect)
 {
-    m_rect = rect;
     prepareGeometryChange();
-    updateGeometry();
+    m_rect = rect;
+    QVector<PieSliceLayout> sliceLayout = calculateLayout();
+    applyLayout(sliceLayout);
+    update();
 }
 
-void PiePresenter::updateGeometry()
-{
-    if (!m_rect.isValid() || m_rect.isEmpty())
-        return;
 
+QVector<PieSliceLayout> PiePresenter::calculateLayout()
+{
     // find pie center coordinates
     QPointF center;
     center.setX(m_rect.left() + (m_rect.width() * m_series->pieHorizontalPosition()));
@@ -91,66 +78,64 @@ void PiePresenter::updateGeometry()
     // apply size factor
     radius *= m_series->pieSize();
 
-    // update slices
-    if (m_pieCenter != center || m_pieRadius != radius) {
-        m_pieCenter = center;
-        m_pieRadius = radius;
-        //qDebug() << "PiePresenter::updateGeometry()" << m_rect << m_pieCenter << m_pieRadius;
-        foreach (PieSlice* s, m_slices.values()) {
-            s->setPieCenterAndRadius(center, radius);
-            s->updateGeometry();
-            s->update();
-        }
+    QVector<PieSliceLayout> layout;
+    foreach (QPieSlice* s, m_series->slices()) {
+        PieSliceLayout sliceLayout;
+        sliceLayout.m_data = s;
+        sliceLayout.m_center = PieSlice::sliceCenter(center, radius, s);
+        sliceLayout.m_radius = radius;
+        sliceLayout.m_startAngle = s->startAngle();
+        sliceLayout.m_angleSpan = s->m_angleSpan;
+        layout << sliceLayout;
     }
 
-    update();
+    return layout;
 }
 
-void PiePresenter::addSlice(QPieSlice* sliceData)
+void PiePresenter::applyLayout(const QVector<PieSliceLayout> &layout)
 {
-    //qDebug() << "PiePresenter::addSlice()" << sliceData;
-
-    if (m_slices.keys().contains(sliceData)) {
-        Q_ASSERT(0); // TODO: how to handle this nicely?
-        return;
-    }
-
-    // create slice
-    PieSlice *slice = new PieSlice(this);
-    slice->setPieCenterAndRadius(m_pieCenter, m_pieRadius);
-    slice->updateData(sliceData);
-    slice->updateGeometry();
-    slice->update();
-    m_slices.insert(sliceData, slice);
-
-    // connect signals
-    connect(slice, SIGNAL(clicked()), sliceData, SIGNAL(clicked()));
-    connect(slice, SIGNAL(hoverEnter()), sliceData, SIGNAL(hoverEnter()));
-    connect(slice, SIGNAL(hoverLeave()), sliceData, SIGNAL(hoverLeave()));
+    //if(m_animator)
+    //        m_animator->applyLayout(this,points);
+    //else
+    setLayout(layout);
 }
 
-void PiePresenter::updateSlice(QPieSlice* sliceData)
+void PiePresenter::setLayout(const QVector<PieSliceLayout> &layout)
 {
-    //qDebug() << "PiePresenter::updateSlice()" << sliceData;
+    foreach (PieSliceLayout l, layout) {
+
+        // find slice
+        PieSlice *slice = m_slices.value(l.m_data);
+        if (!slice) {
+            // add a new slice
+            slice = new PieSlice(this);
+            m_slices.insert(l.m_data, slice);
+
+            // connect signals
+            connect(l.m_data, SIGNAL(changed()), this, SLOT(handleSliceChanged()));
+            connect(slice, SIGNAL(clicked()), l.m_data, SIGNAL(clicked()));
+            connect(slice, SIGNAL(hoverEnter()), l.m_data, SIGNAL(hoverEnter()));
+            connect(slice, SIGNAL(hoverLeave()), l.m_data, SIGNAL(hoverLeave()));
+        }
 
-    if (!m_slices.contains(sliceData)) {
-        Q_ASSERT(0); // TODO: how to handle this nicely?
-        return;
+        // update
+        slice->setLayout(l);
+        slice->updateGeometry();
+        slice->update();
     }
 
-    m_slices[sliceData]->updateData(sliceData);
-}
+    // delete slices
+    foreach (QPieSlice *s, m_slices.keys()) {
 
-void PiePresenter::deleteSlice(QPieSlice* sliceData)
-{
-    //qDebug() << "PiePresenter::deleteSlice()" << sliceData;
+        bool found = false;
+        foreach (PieSliceLayout l, layout) {
+            if (l.m_data == s)
+                found = true;
+        }
 
-    if (!m_slices.contains(sliceData)) {
-        Q_ASSERT(0); // TODO: how to handle this nicely?
-        return;
+        if (!found)
+            delete m_slices.take(s);
     }
-
-    delete m_slices.take(sliceData);
 }
 
 #include "moc_piepresenter_p.cpp"
diff --git a/src/piechart/piepresenter_p.h b/src/piechart/piepresenter_p.h
index 5671e3a..082544c 100644
--- a/src/piechart/piepresenter_p.h
+++ b/src/piechart/piepresenter_p.h
@@ -1,13 +1,13 @@
 #ifndef PIEPRESENTER_H
 #define PIEPRESENTER_H
 
-#include "chartitem_p.h"
 #include "qpieseries.h"
-#include <QSignalMapper>
+#include "chartitem_p.h"
+#include "pieslice_p.h"
 
 class QGraphicsItem;
 QTCOMMERCIALCHART_BEGIN_NAMESPACE
-class PieSlice;
+class QPieSlice;
 
 class PiePresenter : public QObject, public ChartItem
 {
@@ -23,15 +23,15 @@ public: // from QGraphicsItem
     void paint(QPainter *, const QStyleOptionGraphicsItem *, QWidget *);
 
 public Q_SLOTS:
-    void handleSeriesChanged(const QPieSeries::ChangeSet& changeSet);
-    void handleDomainChanged(const Domain& domain);
+    void handleSeriesChanged();
+    void handleSliceChanged();
+    void handleDomainChanged(qreal, qreal, qreal, qreal);
     void handleGeometryChanged(const QRectF& rect);
-    void updateGeometry();
 
 private:
-    void addSlice(QPieSlice* sliceData);
-    void updateSlice(QPieSlice* sliceData);
-    void deleteSlice(QPieSlice* sliceData);
+    QVector<PieSliceLayout> calculateLayout();
+    void applyLayout(const QVector<PieSliceLayout> &layout);
+    void setLayout(const QVector<PieSliceLayout> &layout);
 
 private:
     friend class PieSlice;
diff --git a/src/piechart/pieslice.cpp b/src/piechart/pieslice.cpp
index 7634f59..35b9577 100644
--- a/src/piechart/pieslice.cpp
+++ b/src/piechart/pieslice.cpp
@@ -22,7 +22,6 @@ QPointF offset(qreal angle, qreal length)
 
 PieSlice::PieSlice(QGraphicsItem* parent)
     :QGraphicsObject(parent),
-    m_pieRadius(0),
     m_startAngle(0),
     m_angleSpan(0),
     m_isExploded(false),
@@ -88,15 +87,15 @@ void PieSlice::mousePressEvent(QGraphicsSceneMouseEvent* /*event*/)
     emit clicked();
 }
 
-void PieSlice::setPieCenterAndRadius(QPointF center, qreal radius)
+void PieSlice::setLayout(PieSliceLayout layout)
 {
-    m_pieCenter = center;
-    m_pieRadius = radius;
+    m_layout = layout;
+    updateData(layout.m_data);
 }
 
 void PieSlice::updateGeometry()
 {
-    if (m_pieRadius <= 0)
+    if (m_layout.m_radius <= 0)
         return;
 
     prepareGeometryChange();
@@ -104,14 +103,14 @@ void PieSlice::updateGeometry()
     // update slice path
     qreal centerAngle;
     QPointF armStart;
-    m_slicePath = slicePath(m_pieCenter, m_pieRadius, m_startAngle, m_angleSpan, m_isExploded, m_pieRadius * m_explodeDistanceFactor, &centerAngle, &armStart);
+    m_slicePath = slicePath(m_layout.m_center, m_layout.m_radius, m_startAngle, m_angleSpan, &centerAngle, &armStart);
 
     // update text rect
     m_labelTextRect = labelTextRect(m_labelFont, m_labelText);
 
     // update label arm path
     QPointF labelTextStart;
-    m_labelArmPath = labelArmPath(armStart, centerAngle, m_pieRadius * m_labelArmLengthFactor, m_labelTextRect.width(), &labelTextStart);
+    m_labelArmPath = labelArmPath(armStart, centerAngle, m_layout.m_radius * m_labelArmLengthFactor, m_labelTextRect.width(), &labelTextStart);
 
     // update text position
     m_labelTextRect.moveBottomLeft(labelTextStart);
@@ -135,12 +134,21 @@ void PieSlice::updateData(const QPieSlice* sliceData)
     m_labelFont = sliceData->labelFont();
     m_labelArmLengthFactor = sliceData->labelArmLengthFactor();
     m_labelArmPen = sliceData->labelArmPen();
+}
 
-    updateGeometry();
-    update();
+QPointF PieSlice::sliceCenter(QPointF point, qreal radius, QPieSlice *slice)
+{
+    if (slice->isExploded()) {
+        qreal centerAngle = slice->startAngle() + (slice->m_angleSpan/2);
+        qreal len = radius * slice->explodeDistanceFactor();
+        qreal dx = qSin(centerAngle*(PI/180)) * len;
+        qreal dy = -qCos(centerAngle*(PI/180)) * len;
+        point += QPointF(dx, dy);
+    }
+    return point;
 }
 
-QPainterPath PieSlice::slicePath(QPointF center, qreal radius, qreal startAngle, qreal angleSpan, bool exploded, qreal explodeDistance, qreal* centerAngle, QPointF* armStart)
+QPainterPath PieSlice::slicePath(QPointF center, qreal radius, qreal startAngle, qreal angleSpan, qreal* centerAngle, QPointF* armStart)
 {
     // calculate center angle
     *centerAngle = startAngle + (angleSpan/2);
@@ -148,13 +156,6 @@ QPainterPath PieSlice::slicePath(QPointF center, qreal radius, qreal startAngle,
     // calculate slice rectangle
     QRectF rect(center.x()-radius, center.y()-radius, radius*2, radius*2);
 
-    // adjust rect for exploding
-    if (exploded) {
-        qreal dx = qSin(*centerAngle*(PI/180)) * explodeDistance;
-        qreal dy = -qCos(*centerAngle*(PI/180)) * explodeDistance;
-        rect.translate(dx, dy);
-    }
-
     // slice path
     // TODO: draw the shape so that it might have a hole in the center
     QPainterPath path;
@@ -164,10 +165,7 @@ QPainterPath PieSlice::slicePath(QPointF center, qreal radius, qreal startAngle,
 
     // calculate label arm start point
     *armStart = center;
-    if (exploded)
-        *armStart += offset(*centerAngle, explodeDistance + radius + PIESLICE_LABEL_GAP);
-    else
-        *armStart += offset(*centerAngle, radius + PIESLICE_LABEL_GAP);
+    *armStart += offset(*centerAngle, radius + PIESLICE_LABEL_GAP);
 
     return path;
 }
diff --git a/src/piechart/pieslice_p.h b/src/piechart/pieslice_p.h
index 760c8c7..783e9ff 100644
--- a/src/piechart/pieslice_p.h
+++ b/src/piechart/pieslice_p.h
@@ -16,6 +16,16 @@ class PiePresenter;
 class PieSliceLabel;
 class QPieSlice;
 
+class PieSliceLayout
+{
+public:
+    QPieSlice* m_data;
+    QPointF m_center;
+    qreal m_radius;
+    qreal m_startAngle;
+    qreal m_angleSpan;
+};
+
 class PieSlice : public QGraphicsObject
 {
     Q_OBJECT
@@ -37,19 +47,17 @@ Q_SIGNALS:
     void hoverEnter();
     void hoverLeave();
 
-public Q_SLOTS:
-    void setPieCenterAndRadius(QPointF center, qreal radius);
+public:
+    void setLayout(PieSliceLayout layout);
     void updateGeometry();
     void updateData(const QPieSlice *sliceData);
-
-public:
-    static QPainterPath slicePath(QPointF center, qreal radius, qreal startAngle, qreal angleSpan, bool exploded, qreal explodeDistance, qreal* centerAngle, QPointF* armStart);
+    static QPointF sliceCenter(QPointF point, qreal radius, QPieSlice *slice);
+    static QPainterPath slicePath(QPointF center, qreal radius, qreal startAngle, qreal angleSpan, qreal* centerAngle, QPointF* armStart);
     static QPainterPath labelArmPath(QPointF start, qreal angle, qreal length, qreal textWidth, QPointF* textStart);
     static QRectF labelTextRect(QFont font, QString text);
 
 private:
-    QPointF m_pieCenter;
-    qreal m_pieRadius;
+    PieSliceLayout m_layout;
 
     QPainterPath m_slicePath;
     qreal m_startAngle;
diff --git a/src/piechart/qpieseries.cpp b/src/piechart/qpieseries.cpp
index d2ef8c7..c0f311a 100644
--- a/src/piechart/qpieseries.cpp
+++ b/src/piechart/qpieseries.cpp
@@ -147,11 +147,9 @@ void QPieSeries::replace(QList<QPieSlice*> slices)
 */
 void QPieSeries::add(QList<QPieSlice*> slices)
 {
-    ChangeSet changeSet;
     foreach (QPieSlice* s, slices) {
         s->setParent(this);
         m_slices << s;
-        changeSet.appendAdded(s);
     }
 
     updateDerivativeData();
@@ -163,7 +161,7 @@ void QPieSeries::add(QList<QPieSlice*> slices)
         connect(s, SIGNAL(hoverLeave()), this, SLOT(sliceHoverLeave()));
     }
 
-    emit changed(changeSet);
+    emit changed();
 }
 
 /*!
@@ -208,15 +206,12 @@ void QPieSeries::remove(QPieSlice* slice)
         Q_ASSERT(0); // TODO: how should this be reported?
         return;
     }
+    emit changed();
 
-    ChangeSet changeSet;
-    changeSet.appendRemoved(slice);
-    emit changed(changeSet);
+    updateDerivativeData();
 
     delete slice;
     slice = NULL;
-
-    updateDerivativeData();
 }
 
 /*!
@@ -227,13 +222,13 @@ void QPieSeries::clear()
     if (m_slices.count() == 0)
         return;
 
-    ChangeSet changeSet;
     foreach (QPieSlice* s, m_slices) {
-        changeSet.appendRemoved(s);
         m_slices.removeOne(s);
         delete s;
     }
-    emit changed(changeSet);
+
+    emit changed();
+
     updateDerivativeData();
 }
 
@@ -276,7 +271,7 @@ void QPieSeries::setPiePosition(qreal relativeHorizontalPosition, qreal relative
     if (m_pieRelativeHorPos != relativeHorizontalPosition || m_pieRelativeVerPos != relativeVerticalPosition) {
         m_pieRelativeHorPos = relativeHorizontalPosition;
         m_pieRelativeVerPos = relativeVerticalPosition;
-        emit piePositionChanged();
+        emit changed();
     }
 }
 
@@ -330,7 +325,7 @@ void QPieSeries::setPieSize(qreal relativeSize)
 
     if (m_pieRelativeSize != relativeSize) {
         m_pieRelativeSize = relativeSize;
-        emit pieSizeChanged();
+        emit changed();
     }
 }
 
@@ -429,10 +424,9 @@ qreal QPieSeries::total() const
 }
 
 /*!
-    \fn void QPieSeries::changed(const QPieSeries::ChangeSet& changeSet)
+    \fn void QPieSeries::changed()
 
     This signal emitted when something has changed in the series.
-    The \a changeSet contains the details of which slices have been added, changed or removed.
 
     \sa QPieSeries::ChangeSet, QPieSlice::changed()
 */
@@ -461,31 +455,10 @@ qreal QPieSeries::total() const
     \sa QPieSlice::hoverLeave()
 */
 
-/*!
-    \fn void QPieSeries::pieSizeChanged()
-
-    This signal is emitted when size factor has been changed.
-
-    \sa pieSize(), setPieSize()
-*/
-
-/*!
-    \fn void QPieSeries::piePositionChanged()
-
-    This signal is emitted when position of the pie has been changed.
-
-    \sa pieHorizontalPosition(), pieVerticalPosition(), setPiePosition()
-*/
-
 void QPieSeries::sliceChanged()
 {
     QPieSlice* slice = qobject_cast<QPieSlice *>(sender());
     Q_ASSERT(m_slices.contains(slice));
-
-    ChangeSet changeSet;
-    changeSet.appendChanged(slice);
-    emit changed(changeSet);
-
     updateDerivativeData();
 }
 
diff --git a/src/piechart/qpieseries.h b/src/piechart/qpieseries.h
index a2f3c5e..5bfb805 100644
--- a/src/piechart/qpieseries.h
+++ b/src/piechart/qpieseries.h
@@ -97,11 +97,7 @@ Q_SIGNALS:
     void clicked(QPieSlice* slice);
     void hoverEnter(QPieSlice* slice);
     void hoverLeave(QPieSlice* slice);
-
-    void pieSizeChanged();
-    void piePositionChanged();
-
-    void changed(const QPieSeries::ChangeSet& changeSet); // TODO: hide this in PIMPL
+    void changed(); // TODO: hide this in PIMPL
 
 private Q_SLOTS: // TODO: should be private and not visible in the interface at all
     void sliceChanged();