refs #9428. Swap in PeakClusterProjection into integration.

refactoring step. Common code usage.

Code/Mantid/Framework/Crystal/src/IntegratePeaksUsingClusters.cpp

@@ -256,10 +256,10 @@ namespace Mantid
       ConnectedComponentMappingTypes::ClusterMap& clusterMap = clusters.get<1>();
       // Extract the labeled image
       IMDHistoWorkspace_sptr outHistoWS = clusters.get<0>();
-      // Make a peak transform so that we can understand a peak in the context of the mdworkspace coordinate setup.
-      PeakTransform_sptr peakTransform = makePeakTransform(mdWS.get());
       // Labels taken by peaks.
       std::map<size_t, size_t> labelsTakenByPeaks;
+      // Make a peak transform so that we can understand a peak in the context of the mdworkspace coordinate setup.
+      PeakClusterProjection projection(outHistoWS); // Projection of PeaksWorkspace over labelled cluster workspace.
 
       progress.doReport("Performing Peak Integration");
       g_log.information("Starting Integration");
@@ -269,8 +269,7 @@ namespace Mantid
       {
         PARALLEL_START_INTERUPT_REGION
         IPeak& peak = peakWS->getPeak(i);
-        const V3D& peakCenterInMDFrame = peakTransform->transformPeak(peak);
-        const Mantid::signal_t signalValue = outHistoWS->getSignalAtVMD(peakCenterInMDFrame, NoNormalization); // No normalization when extracting label ids!
+        const Mantid::signal_t signalValue = projection.signalAtPeakCenter(peak); // No normalization when extracting label ids!
         if(boost::math::isnan(signalValue))
         {
           g_log.warning() << "Warning: image for integration is off edge of detector for peak " << i << std::endl;