ENH: Transfer function : mask added for gradient item

Libs/Widgets/ctkTransferFunctionGradientItem.cpp

@@ -43,6 +43,7 @@ ctkTransferFunctionGradientItem::ctkTransferFunctionGradientItem(
   ctkTransferFunction* transferFunction, QGraphicsItem* parentItem)
   :ctkTransferFunctionItem(transferFunction, parentItem)
 {
+ this->Mask = true;
 }
 
 //-----------------------------------------------------------------------------
@@ -56,8 +57,39 @@ void ctkTransferFunctionGradientItem::paint(
 {
   ctkTransferFunctionScene* tfScene = dynamic_cast<ctkTransferFunctionScene*>(this->scene());
   Q_ASSERT(tfScene);
-  
-  const QGradient& gradient = tfScene->gradient();
-  painter->fillRect(this->rect(), gradient);
+
+  if ( this->mask() )
+    {
+    const QGradient& gradient = tfScene->gradient();
+    const QPainterPath& curve = tfScene->curve();
+    QPainterPath closedPath = curve;
+    QRectF position = this->rect();
+    // link to last point
+    closedPath.lineTo(position.x() + position.width(), position.y() + position.height());
+    // link to first point
+    closedPath.lineTo(position.x(), position.y() + position.height());
+    //Don,t need to close because automatic
+    QPen pen(QColor(255, 255, 255, 191), 1);
+    pen.setCosmetic(true);
+    painter->setPen(pen);
+    painter->setBrush(gradient);
+    painter->drawPath(closedPath);
+    }
+  else
+    {
+    const QGradient& gradient = tfScene->gradient();
+    painter->fillRect(this->rect(), gradient);
+    }
+}
+
+//-----------------------------------------------------------------------------
+bool ctkTransferFunctionGradientItem::mask() const
+{
+  return this->Mask;
 }
 
+//-----------------------------------------------------------------------------
+void ctkTransferFunctionGradientItem::setMask( bool mask )
+{
+  this->Mask = mask;
+}

Libs/Widgets/ctkTransferFunctionGradientItem.h

@@ -35,6 +35,7 @@
 class CTK_WIDGETS_EXPORT ctkTransferFunctionGradientItem: public ctkTransferFunctionItem
 {
   Q_OBJECT
+  Q_PROPERTY(bool Mask READ mask WRITE setMask)
 public:
   ctkTransferFunctionGradientItem(QGraphicsItem* parent = 0);
   ctkTransferFunctionGradientItem(ctkTransferFunction* transferFunction, 
@@ -42,6 +43,12 @@ public:
   virtual ~ctkTransferFunctionGradientItem();
 
   virtual void paint(QPainter * painter, const QStyleOptionGraphicsItem * option, QWidget * widget = 0);
+
+  bool mask()const;
+  void setMask(bool mask);
+
+private:
+  bool Mask;
 };
 
 #endif