ENH: Add ctkTransferFunctionWidget, ctkTransferFunctionItem, ctkTransferFunctionGradientItem and ctkTransferFunctionControlPointsItem

Using the Qt Graphics View Architecture, ctkTransferFunctionWidget is a QGraphicsView that populate a GraphicsScene with a ctkTransferFunctionGradientItem and a ctkTransferFunctionControlPointsItem. The main purpose of the widget is to represent and manipulate any ctkTransferFunction.

Libs/Widgets/CMakeLists.txt

@@ -16,12 +16,18 @@ SET(KIT_SRCS
   ctkMatrixWidget.h
   ctkSettings.cpp
   ctkSettings.h
+  ctkTransferFunctionItems.cpp
+  ctkTransferFunctionItems.h
+  ctkTransferFunctionWidget.cpp
+  ctkTransferFunctionWidget.h
   )
 
 # Headers that should run through moc
 SET(KIT_MOC_SRCS
   ctkMatrixWidget.h
   ctkSettings.h
+  ctkTransferFunctionItems.h
+  ctkTransferFunctionWidget.h
   )
 
 # UI files

Libs/Widgets/ctkTransferFunctionItems.cpp

@@ -0,0 +1,407 @@
+/*=========================================================================
+
+  Library:   ctk
+
+  Copyright (c) Kitware Inc. 
+  All rights reserved.
+  Distributed under a BSD License. See LICENSE.txt file.
+
+  This software is distributed "AS IS" WITHOUT ANY WARRANTY; without even
+  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the above copyright notice for more information.
+
+=========================================================================*/
+
+/// Qt includes
+#include <QColor>
+#include <QDebug>
+#include <QLinearGradient>
+#include <QGraphicsSceneMouseEvent>
+#include <QPainter>
+#include <QtGlobal>
+#include <QVariant>
+
+/// CTK includes
+#include "ctkTransferFunction.h"
+#include "ctkTransferFunctionItems.h"
+
+//-----------------------------------------------------------------------------
+class ctkTransferFunctionItemPrivate : 
+  public ctkPrivate<ctkTransferFunctionItem>
+{
+public:
+  ctkTransferFunctionItemPrivate();
+
+  QRectF               Rect;
+  ctkTransferFunction* TransferFunction;
+};
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionItemPrivate::ctkTransferFunctionItemPrivate()
+{
+  this->TransferFunction = 0;
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionItem::ctkTransferFunctionItem(QGraphicsItem* parentGraphicsItem)
+  :QGraphicsObject(parentGraphicsItem)
+{
+  CTK_INIT_PRIVATE(ctkTransferFunctionItem);
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionItem::ctkTransferFunctionItem(
+  ctkTransferFunction* transferFunction, QGraphicsItem* parentItem)
+  :QGraphicsObject(parentItem)
+{
+  CTK_INIT_PRIVATE(ctkTransferFunctionItem);
+  this->setTransferFunction(transferFunction);
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionItem::~ctkTransferFunctionItem()
+{
+  
+}
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionItem::setTransferFunction(ctkTransferFunction* transferFunction)
+{
+  CTK_D(ctkTransferFunctionItem);
+  if (d->TransferFunction == transferFunction)
+    {
+    return;
+    }
+  d->TransferFunction = transferFunction;
+  connect(d->TransferFunction, SIGNAL(changed()),
+          this, SLOT(onTransferFunctionChanged()));
+  this->update();
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunction* ctkTransferFunctionItem::transferFunction() const
+{
+  CTK_D(const ctkTransferFunctionItem);
+  return d->TransferFunction;
+}
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionItem::onTransferFunctionChanged()
+{
+  this->update();
+}
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionItem::setRect(const QRectF& newRect)
+{
+  CTK_D(ctkTransferFunctionItem);
+  if (d->Rect == newRect)
+    {
+    return;
+    }
+  d->Rect = newRect;
+  this->update();
+}
+
+//-----------------------------------------------------------------------------
+QRectF ctkTransferFunctionItem::rect() const
+{
+  CTK_D(const ctkTransferFunctionItem);
+  return d->Rect;
+}
+
+//-----------------------------------------------------------------------------
+QRectF ctkTransferFunctionItem::boundingRect()const
+{
+  CTK_D(const ctkTransferFunctionItem);
+  return d->Rect;
+}
+
+//-----------------------------------------------------------------------------
+QList<QPointF> ctkTransferFunctionItem::bezierParams(
+  ctkControlPoint* start, ctkControlPoint* end) const
+{
+  Q_ASSERT(start);
+  Q_ASSERT(end);
+  QList<QPointF> points; 
+  
+  points << QPointF(start->Pos, this->y(start->Value));
+  points << QPointF(end->Pos, this->y(end->Value));
+
+  ctkBezierControlPoint* bezierCP = dynamic_cast<ctkBezierControlPoint*>(start);
+  if (!bezierCP)
+    {// just duplicate start and end into p1 and p2
+    points << points[0];
+    points << points[1];
+    return points;
+    }
+  
+  points << QPointF(bezierCP->P1, this->y(bezierCP->ValueP1));
+  points << QPointF(bezierCP->P2, this->y(bezierCP->ValueP2));
+  return points;
+}
+
+//-----------------------------------------------------------------------------
+qreal ctkTransferFunctionItem::y(const QVariant& v) const
+{ 
+  Q_ASSERT(v.canConvert<qreal>() || v.canConvert<QColor>());
+  if (v.canConvert<QColor>())
+    {
+    return v.value<QColor>().alphaF();
+    }
+  return v.toReal();
+}
+
+//-----------------------------------------------------------------------------
+QColor ctkTransferFunctionItem::color(const QVariant& v) const
+{ 
+  Q_ASSERT(v.canConvert<QColor>());
+  if (v.canConvert<QColor>())
+    {
+    return v.value<QColor>();
+    }
+  return QColor();
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionGradientItem::ctkTransferFunctionGradientItem(QGraphicsItem* parentGraphicsItem)
+  :ctkTransferFunctionItem(parentGraphicsItem)
+{
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionGradientItem::ctkTransferFunctionGradientItem(
+  ctkTransferFunction* transferFunction, QGraphicsItem* parentItem)
+  :ctkTransferFunctionItem(transferFunction, parentItem)
+{
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionGradientItem::~ctkTransferFunctionGradientItem()
+{  
+}
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionGradientItem::paint(
+  QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget)
+{
+  int count = this->transferFunction() ? this->transferFunction()->count() : 0;
+  if (count <= 0)
+    {
+    painter->fillRect(this->rect(),Qt::black);
+    return;
+    }
+  qreal range[2];
+  this->transferFunction()->range(range);
+  qreal rangeDiff = this->rect().width() / (range[1] - range[0]);
+  ctkControlPoint* startCP = this->transferFunction()->controlPoint(0);
+  ctkControlPoint* endCP = 0;
+  
+  qreal start = startCP->Pos * rangeDiff;
+  qreal end = 0;
+  for(int i = 1; i < count; ++i)
+    {
+    endCP = this->transferFunction()->controlPoint(i);
+    // TODO, use Bezier points for a finer gradient
+    end = endCP->Pos * rangeDiff;
+    QLinearGradient gradient(start,0, end, 0);
+    gradient.setColorAt(0, this->color(startCP->Value));
+    gradient.setColorAt(1, this->color(endCP->Value));
+    QRectF itemRect = QRectF(start, 0, end - start, 
+                             this->rect().height());
+    if (i==1)
+      {
+      itemRect.setLeft(0.);
+      }
+    if (i == count -1)
+      {
+      itemRect.setRight(this->rect().width());
+      }
+    painter->fillRect(itemRect, gradient);
+    delete startCP;
+    startCP = endCP;
+    start = end;
+    }
+  if (startCP)
+    {
+    delete startCP;
+    }
+}
+
+//-----------------------------------------------------------------------------
+class ctkTransferFunctionControlPointsItemPrivate: 
+  public ctkPrivate<ctkTransferFunctionControlPointsItem>
+{
+public:
+  ctkTransferFunctionControlPointsItemPrivate();
+  void init();
+  QList<QPointF> ControlPoints;
+  QSizeF         PointSize;
+  int            SelectedPoint;
+};
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionControlPointsItemPrivate::ctkTransferFunctionControlPointsItemPrivate()
+{
+  this->PointSize = QSizeF(10.,10.);
+  this->SelectedPoint = -1;
+}
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionControlPointsItemPrivate::init()
+{
+  CTK_P(ctkTransferFunctionControlPointsItem);
+  p->setAcceptedMouseButtons(Qt::LeftButton);
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionControlPointsItem::ctkTransferFunctionControlPointsItem(QGraphicsItem* parentGraphicsItem)
+  :ctkTransferFunctionItem(parentGraphicsItem)
+{
+  CTK_INIT_PRIVATE(ctkTransferFunctionControlPointsItem);
+  ctk_d()->init();
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionControlPointsItem::ctkTransferFunctionControlPointsItem(
+  ctkTransferFunction* transferFunction, QGraphicsItem* parentItem)
+  :ctkTransferFunctionItem(transferFunction, parentItem)
+{
+  CTK_INIT_PRIVATE(ctkTransferFunctionControlPointsItem);
+  ctk_d()->init();
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionControlPointsItem::~ctkTransferFunctionControlPointsItem()
+{  
+}
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionControlPointsItem::paint(
+  QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget)
+{
+  CTK_D(ctkTransferFunctionControlPointsItem);
+  int count = this->transferFunction() ? this->transferFunction()->count() : 0;
+  if (count <= 0)
+    {
+    return;
+    }
+  qreal rangeX[2];
+  this->transferFunction()->range(rangeX);
+  qreal rangeXDiff = this->rect().width() / (rangeX[1] - rangeX[0]);
+  QVariant rangeY[2];
+  rangeY[0] = this->transferFunction()->minValue();
+  rangeY[1] = this->transferFunction()->maxValue();
+  qreal rangeYDiff = this->rect().height();
+  if (rangeY[0].canConvert<qreal>())
+    {
+    rangeYDiff /= rangeY[1].toReal() - rangeY[0].toReal();
+    }
+  else if (rangeY[0].canConvert<qreal>())
+    {
+    rangeYDiff /= rangeY[1].value<QColor>().alphaF() - rangeY[0].value<QColor>().alphaF();
+    }
+  else
+    {
+    Q_ASSERT(rangeY[0].canConvert<qreal>() ||
+             rangeY[0].canConvert<QColor>());
+    }
+  ctkControlPoint* startCP = this->transferFunction()->controlPoint(0);
+  ctkControlPoint* endCP = 0;
+  qreal start = 0;
+  qreal end = 0;
+
+  QPainterPath path;
+
+  QPointF startPos(startCP->Pos, this->y(startCP->Value));
+  startPos.rx() *= rangeXDiff;
+  startPos.setY(this->rect().height() 
+                - startPos.y() * rangeYDiff);
+  
+  d->ControlPoints.clear();
+  d->ControlPoints << startPos;
+
+  path.moveTo(startPos);
+  for(int i = 1; i < count; ++i)
+    {
+    endCP = this->transferFunction()->controlPoint(i);
+    QList<QPointF> points = this->bezierParams(startCP, endCP);
+    QList<QPointF>::iterator it = points.begin();
+    for ( ; it != points.end(); ++it)
+      {
+      (*it).rx() *= rangeXDiff;
+      (*it).setY(this->rect().height() 
+                 - (*it).y() * rangeYDiff);
+      }
+    d->ControlPoints << points[1];
+    path.cubicTo(points[2], points[3], points[1]);
+    //qDebug() << i << points[0] << points[2] << points[3] << points[1];
+    delete startCP;
+    startCP = endCP;
+    }
+  if (startCP)
+    {
+    delete startCP;
+    }
+  painter->setRenderHint(QPainter::Antialiasing);
+  painter->setPen(QPen(QColor(255, 255, 255, 191), 1));
+  painter->drawPath(path);
+
+  QPainterPath points;
+  foreach(const QPointF point, d->ControlPoints)
+    {
+    points.addEllipse(point, d->PointSize.width(), d->PointSize.height());
+    }
+  painter->setBrush(QBrush(QColor(191, 191, 191, 127)));
+  painter->drawPath(points);
+}
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionControlPointsItem::mousePressEvent(QGraphicsSceneMouseEvent* e)
+{
+  CTK_D(ctkTransferFunctionControlPointsItem);
+  QRectF pointArea(QPointF(0,0), d->PointSize*2.);
+  d->SelectedPoint = -1;
+  for(int i = 0; i < d->ControlPoints.count(); ++i)
+    {
+    pointArea.moveCenter(d->ControlPoints[i]);
+    if (pointArea.contains(e->pos()))
+      {
+      d->SelectedPoint = i;
+      break;
+      }
+    }
+  if (d->SelectedPoint < 0)
+    {
+    e->ignore();
+    }
+}
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionControlPointsItem::mouseMoveEvent(QGraphicsSceneMouseEvent* e)
+{
+  CTK_D(ctkTransferFunctionControlPointsItem);
+  if (d->SelectedPoint < 0)
+    {
+    e->ignore();
+    return;
+    }
+  qreal range[2];
+  this->transferFunction()->range(range);
+  qreal newPos = range[0] + e->pos().x() / (this->rect().width() / (range[1] - range[0]));
+  newPos = qBound(range[0], newPos, range[1]);
+  this->transferFunction()->setControlPointPos(d->SelectedPoint, newPos);
+  //this->transferFunction()->setControlPointValue(d->SelectedPoint, e->y());
+}
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionControlPointsItem::mouseReleaseEvent(QGraphicsSceneMouseEvent* e)
+{
+  CTK_D(ctkTransferFunctionControlPointsItem);
+  if (d->SelectedPoint < 0)
+    {
+    e->ignore();
+    return;
+    }
+  d->SelectedPoint = -1;
+}

Libs/Widgets/ctkTransferFunctionItems.h

@@ -0,0 +1,98 @@
+/*=========================================================================
+
+  Library:   ctk
+
+  Copyright (c) Kitware Inc. 
+  All rights reserved.
+  Distributed under a BSD License. See LICENSE.txt file.
+
+  This software is distributed "AS IS" WITHOUT ANY WARRANTY; without even
+  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the above copyright notice for more information.
+
+=========================================================================*/
+
+#ifndef __ctkTransferFunctionItems_h
+#define __ctkTransferFunctionItems_h
+
+/// Qt includes
+#include <QGraphicsObject>
+
+/// CTK includes
+#include "CTKWidgetsExport.h"
+#include "ctkPimpl.h"
+
+class ctkControlPoint;
+class ctkTransferFunction;
+class ctkTransferFunctionItemPrivate;
+//class ctkTransferFunctionGradientItemPrivate;
+class ctkTransferFunctionControlPointsItemPrivate;
+
+/// 
+/// TODO: should probably derive from QGraphicsItem or QAbstractGraphicsShapeItem
+class CTK_WIDGETS_EXPORT ctkTransferFunctionItem: public QGraphicsObject
+{
+  Q_OBJECT
+public:
+  ctkTransferFunctionItem(QGraphicsItem* parent = 0);
+  ctkTransferFunctionItem(ctkTransferFunction* transferFunction, 
+                                  QGraphicsItem* parent = 0);
+  virtual ~ctkTransferFunctionItem();
+
+  void setTransferFunction(ctkTransferFunction* transferFunction);
+  ctkTransferFunction* transferFunction()const;
+
+  inline void setRect(qreal x, qreal y, qreal width, qreal height);
+  void setRect(const QRectF& rectangle);
+  QRectF rect()const;
+  virtual QRectF boundingRect()const;
+protected:
+  qreal y(const QVariant& v)const;
+  QColor color(const QVariant& v)const;
+
+  QList<QPointF> bezierParams(ctkControlPoint* start, ctkControlPoint* end)const;
+protected slots:
+  virtual void onTransferFunctionChanged();
+private:
+  CTK_DECLARE_PRIVATE(ctkTransferFunctionItem);
+};
+
+void ctkTransferFunctionItem::setRect(qreal x, qreal y, qreal width, qreal height)
+{
+  this->setRect(QRectF(x,y,width,height));
+}
+
+//-----------------------------------------------------------------------------
+class CTK_WIDGETS_EXPORT ctkTransferFunctionGradientItem: public ctkTransferFunctionItem
+{
+  Q_OBJECT
+public:
+  ctkTransferFunctionGradientItem(QGraphicsItem* parent = 0);
+  ctkTransferFunctionGradientItem(ctkTransferFunction* transferFunction, 
+                                  QGraphicsItem* parent = 0);
+  virtual ~ctkTransferFunctionGradientItem();
+
+  virtual void paint(QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget = 0);
+};
+
+
+//-----------------------------------------------------------------------------
+class CTK_WIDGETS_EXPORT ctkTransferFunctionControlPointsItem: public ctkTransferFunctionItem
+{
+  Q_OBJECT
+public:
+  explicit ctkTransferFunctionControlPointsItem(QGraphicsItem* parent = 0);
+  ctkTransferFunctionControlPointsItem(ctkTransferFunction* transferFunction, 
+                                       QGraphicsItem* parent = 0);
+  virtual ~ctkTransferFunctionControlPointsItem();
+
+  virtual void paint(QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget = 0);
+protected:
+  virtual void mousePressEvent(QGraphicsSceneMouseEvent* e);
+  virtual void mouseMoveEvent(QGraphicsSceneMouseEvent* e);
+  virtual void mouseReleaseEvent(QGraphicsSceneMouseEvent* e);
+private:
+  CTK_DECLARE_PRIVATE(ctkTransferFunctionControlPointsItem);
+};
+
+#endif

Libs/Widgets/ctkTransferFunctionWidget.cpp

@@ -0,0 +1,106 @@
+/*=========================================================================
+
+  Library:   ctk
+
+  Copyright (c) Kitware Inc. 
+  All rights reserved.
+  Distributed under a BSD License. See LICENSE.txt file.
+
+  This software is distributed "AS IS" WITHOUT ANY WARRANTY; without even
+  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the above copyright notice for more information.
+
+=========================================================================*/
+/// Qt includes
+#include <QGraphicsScene>
+#include <QResizeEvent>
+
+/// CTK includes
+#include "ctkTransferFunction.h"
+#include "ctkTransferFunctionWidget.h"
+#include "ctkTransferFunctionItems.h"
+
+//-----------------------------------------------------------------------------
+class ctkTransferFunctionWidgetPrivate: public ctkPrivate<ctkTransferFunctionWidget>
+{
+  CTK_DECLARE_PUBLIC(ctkTransferFunctionWidget);
+public:
+  void init();
+  ctkTransferFunction* TransferFunction;
+};
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionWidgetPrivate::init()
+{
+  CTK_P(ctkTransferFunctionWidget);
+  p->setScene(new QGraphicsScene(p));
+  p->setHorizontalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
+  p->setVerticalScrollBarPolicy(Qt::ScrollBarAlwaysOff);
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionWidget::ctkTransferFunctionWidget(QWidget* parentWidget)
+  :QGraphicsView(parentWidget)
+{
+  CTK_INIT_PRIVATE(ctkTransferFunctionWidget);
+  ctk_d()->init();
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionWidget::ctkTransferFunctionWidget(
+  ctkTransferFunction* transferFunction, QWidget* parentWidget)
+  :QGraphicsView(parentWidget)
+{
+  CTK_INIT_PRIVATE(ctkTransferFunctionWidget);
+  ctk_d()->init();
+  this->setTransferFunction(transferFunction);
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunctionWidget::~ctkTransferFunctionWidget()
+{
+}
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionWidget::setTransferFunction(ctkTransferFunction* transferFunction)
+{
+  CTK_D(ctkTransferFunctionWidget);
+  d->TransferFunction = transferFunction;
+  Q_ASSERT(this->scene());
+  this->scene()->clear();
+  ctkTransferFunctionGradientItem* gradient = 
+    new ctkTransferFunctionGradientItem(transferFunction);
+  gradient->setRect(0, 0, this->width(), this->height());
+  this->scene()->addItem(gradient);
+  ctkTransferFunctionControlPointsItem* controlPoints = 
+    new ctkTransferFunctionControlPointsItem(transferFunction);
+  controlPoints->setRect(0, 0, this->width(), this->height());
+  this->scene()->addItem(controlPoints);
+}
+
+//-----------------------------------------------------------------------------
+ctkTransferFunction* ctkTransferFunctionWidget::transferFunction()const
+{
+  return ctk_d()->TransferFunction;
+}
+
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionWidget::resizeEvent(QResizeEvent * event)
+{
+  QRectF sceneRect(QPointF(0,0),event->size());
+  foreach(QGraphicsItem * item, this->scene()->items())
+    {
+    ctkTransferFunctionItem* rectItem = 
+      qgraphicsitem_cast<ctkTransferFunctionItem*>(item);
+    if (rectItem)
+      {
+      rectItem->setRect(sceneRect);
+      }
+    }
+  this->scene()->setSceneRect(sceneRect);
+  
+  this->QGraphicsView::resizeEvent(event);
+  // Control points are resized by the view transform, we want
+  // fixed size control points, lines...
+  //this->fitInView(this->scene()->sceneRect());
+}

Libs/Widgets/ctkTransferFunctionWidget.h

@@ -0,0 +1,45 @@
+/*=========================================================================
+
+  Library:   ctk
+
+  Copyright (c) Kitware Inc. 
+  All rights reserved.
+  Distributed under a BSD License. See LICENSE.txt file.
+
+  This software is distributed "AS IS" WITHOUT ANY WARRANTY; without even
+  the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+  See the above copyright notice for more information.
+
+=========================================================================*/
+
+#ifndef __ctkTransferFunctionWidget_h
+#define __ctkTransferFunctionWidget_h
+
+/// Qt includes
+#include <QGraphicsView>
+
+/// CTK includes
+#include "CTKWidgetsExport.h"
+#include "ctkPimpl.h"
+
+class ctkTransferFunction;
+class ctkTransferFunctionWidgetPrivate;
+
+//-----------------------------------------------------------------------------
+class CTK_WIDGETS_EXPORT ctkTransferFunctionWidget: public QGraphicsView
+{
+  Q_OBJECT;
+public:
+  ctkTransferFunctionWidget(QWidget* parent = 0);
+  ctkTransferFunctionWidget(ctkTransferFunction* transferFunction, QWidget* parent = 0);
+  virtual ~ctkTransferFunctionWidget();
+
+  void setTransferFunction(ctkTransferFunction* transferFunction);
+  ctkTransferFunction* transferFunction()const;
+protected:
+  virtual void resizeEvent(QResizeEvent * event);
+private:
+  CTK_DECLARE_PRIVATE(ctkTransferFunctionWidget);
+};
+
+#endif