[REFAC] extracted function evaluating transfer function

src/modules/pickingDVR/WMPickingDVR.cpp

@@ -526,77 +526,77 @@ std::vector< std::pair< double, WPosition > > WMPickingDVR::sampleIntensityAlong
     return result;
 }
 
-WPosition WMPickingDVR::getPickedDVRPosition(  std::string pickingMode, bool* pickingSuccess )
+double WMPickingDVR::getTFAlpha( const double scalar ) const
 {
-    std::vector< std::pair< double, WPosition > > samples( 0 );
-    samples = sampleIntensityAlongRay();
-    if( samples.size() == 0 )
-    {
-        *pickingSuccess = false;
-    }
-
-    WPosition posPicking = m_posStart;
-
-    double max = 0.0;
-    double min = 0.0;
-    double accAlpha  = 0.0;
-    double accAlphaOld = 0.0;
-    double pickedAlpha = 0.0;
-    double maxValue  = 0.0;
-
-
     // Get transferfunction data
     boost::shared_ptr< WDataSetSingle > transferFunctionData = m_transferFunction->getData();
-    if(!transferFunctionData)
+    if( !transferFunctionData )
     {
-        errorLog()<< "[Invalid transferfunction data]";
-        *pickingSuccess = false;
-        return WPosition();
+        WAssert( false, "Invalid transferfunction data" );
     }
 
     // Get transferfunction values
     boost::shared_ptr< WValueSetBase > transferFunctionValues = transferFunctionData->getValueSet();
 
+
     // Get scalar field
     boost::shared_ptr< WDataSetScalar > scalarData = m_scalarIC->getData();
     if(!scalarData)
     {
-        errorLog()<< "[Invalid scalar field]";
-        return WPosition();
+        WAssert( false, "Invalid scalar field" );
     }
 
-    max  = scalarData->getMax();
-    min  = scalarData->getMin();
-    maxValue = min;
+    const double max = scalarData->getMax();
+    const double min = scalarData->getMin();
 
-    std::vector<double> vecAlphaAcc;
+    // Classification variables
+    const double nominator = scalar - min;
+    double denominator = max - min;
 
-    // Sampling loop
-    for( unsigned int i = 0; i < samples.size(); i++ )
+    if( denominator == 0.0 )
     {
-        // Classification variables
-        double nominator = samples[i].first - min;
-        double denominator = max - min;
+        denominator = 0.0001;
+    }
 
-        if( denominator == 0.0 )
-        {
-            denominator = 0.0001;
-        }
+    // Classification: Convert scalar to color
+    double scalarPercentage = nominator / denominator;
+    int colorIdx = scalarPercentage * transferFunctionValues->size();
+
+    WMPickingColor<double> color;
 
-        // Classification: Convert scalar to color
-        double scalarPercentage = nominator / denominator;
-        int colorIdx = scalarPercentage * transferFunctionValues->size();
+    // Get color from transferfunction
+    color.setRed( transferFunctionData->getSingleRawValue( colorIdx * 4 + 0 ) );
+    color.setGreen( transferFunctionData->getSingleRawValue( colorIdx * 4 + 1 ) );
+    color.setBlue( transferFunctionData->getSingleRawValue( colorIdx * 4 + 2 ) );
+    color.setAlpha( transferFunctionData->getSingleRawValue( colorIdx * 4 + 3 ) );
+    color.normalize();
 
-        WMPickingColor<double> color;
+    return color.getAlpha();
+}
 
-        // Get color from transferfunction
-        color.setRed( transferFunctionData->getSingleRawValue( colorIdx * 4 + 0 ) );
-        color.setGreen( transferFunctionData->getSingleRawValue( colorIdx * 4 + 1 ) );
-        color.setBlue( transferFunctionData->getSingleRawValue( colorIdx * 4 + 2 ) );
-        color.setAlpha( transferFunctionData->getSingleRawValue( colorIdx * 4 + 3 ) );
-        color.normalize();
 
-        double currentAlpha = color.getAlpha();
+WPosition WMPickingDVR::getPickedDVRPosition(  std::string pickingMode, bool* pickingSuccess )
+{
+    std::vector< std::pair< double, WPosition > > samples( 0 );
+    samples = sampleIntensityAlongRay();
+    if( samples.size() == 0 )
+    {
+        *pickingSuccess = false;
+        return WPosition();
+    }
+
+    WPosition posPicking = m_posStart;
+
+    double accAlpha = 0.0;
+    double accAlphaOld = 0.0;
+    double pickedAlpha = 0.0;
+    double maxValue =  -1 * std::numeric_limits< double >::max();;
+
+    std::vector<double> vecAlphaAcc;
+
+    for( unsigned int i = 0; i < samples.size(); i++ )
+    {
+        const double currentAlpha = getTFAlpha( samples[i].first );
         double currentAlphaCorrected;
 
         if( m_opacityCorrectionEnabled->get( true ) )

src/modules/pickingDVR/WMPickingDVR.h

@@ -151,6 +151,15 @@ private:
      */
     std::vector< std::pair< double, WPosition > > sampleIntensityAlongRay();
 
+    /**
+     * Evaluate transfer function.
+     *
+     * \param scalar Evaluate transfer function for this value.
+     *
+     * \returnOpacity obtained from transfer function.
+     */
+    double getTFAlpha( const double scalar ) const;
+
     /**
      * Compute the position picked in the DVR
      *