refs #5167. Blind optimisation.

I havent done any benchmarking, but there are functions being run that dont always need to get run. Ive cached some variables rather than recalculate the results too. Would have been better to benchmark first, but Ill do some proper optimisation under another ticket at a later date.

Code/Mantid/MantidQt/SliceViewer/inc/MantidQtSliceViewer/ConcretePeaksPresenter.h

@@ -36,6 +36,8 @@ namespace MantidQt
       boost::shared_ptr<PeakOverlayViewFactory> m_factory;
       /// Peak transformer
       PeakTransform m_transform;
+      /// current slicing point.
+      double m_slicePoint;
       /// Configurre peak transformations
       bool configureMappingTransform();
       /// Hide all views

Code/Mantid/MantidQt/SliceViewer/inc/MantidQtSliceViewer/PeakOverlayFactory.h

@@ -52,8 +52,6 @@ namespace MantidQt
       QwtPlot * m_plot;
       QWidget * m_parent;
       double m_peakRadius;
-      boost::shared_ptr<PeakOverlayView> createViewAtPoint(const Mantid::Kernel::V3D& position, const double& radius) const;
-
     public:
       PeakOverlayFactory(QwtPlot * plot, QWidget * parent);
       virtual ~PeakOverlayFactory();

Code/Mantid/MantidQt/SliceViewer/inc/MantidQtSliceViewer/SliceViewer.h

@@ -164,7 +164,7 @@ public slots:
   void findRangeSlice();
 
   // Peak overlay methods.
-  void updatePeaksWithSlicePoint();
+  void updatePeakOverlaySliderWidget();
   void enablePeakOverlaysIfAppropriate();
 
 
@@ -275,6 +275,9 @@ public slots:
 
   // -------------------------- Controllers ------------------------
   boost::shared_ptr<PeaksPresenter>  m_peaksPresenter;
+
+  /// Pointer to widget used for peaks sliding.
+  DimensionSliceWidget* m_peaksSliderWidget;
 };
 
 } // namespace SliceViewer

Code/Mantid/MantidQt/SliceViewer/src/ConcretePeaksPresenter.cpp

@@ -21,7 +21,7 @@ namespace SliceViewer
   @param peaksWS : IPeaksWorkspace to visualise (THE MODEL)
   */
   ConcretePeaksPresenter::ConcretePeaksPresenter(PeakOverlayViewFactory* factory, Mantid::API::IPeaksWorkspace_sptr peaksWS) : m_viewPeaks(peaksWS->getNumberPeaks())
-    , m_factory(factory), m_transform("H", "K")
+    , m_factory(factory), m_transform("H", "K"), m_slicePoint(0)
   {
     if(factory == NULL)
     {
@@ -71,9 +71,13 @@ namespace SliceViewer
   */
   void ConcretePeaksPresenter::updateWithSlicePoint(const double& slicePoint)
   {
-    for(VecPeakOverlayView::iterator it = m_viewPeaks.begin(); it != m_viewPeaks.end(); ++it)
+    if(m_slicePoint != slicePoint) // only update if required.
     {
-      (*it)->setSlicePoint(slicePoint);
+      for(VecPeakOverlayView::iterator it = m_viewPeaks.begin(); it != m_viewPeaks.end(); ++it)
+      {
+        (*it)->setSlicePoint(slicePoint);
+      }
+      m_slicePoint = slicePoint;
     }
   }
 

Code/Mantid/MantidQt/SliceViewer/src/PeakOverlayFactory.cpp

@@ -24,12 +24,7 @@ namespace MantidQt
 
     boost::shared_ptr<PeakOverlayView> PeakOverlayFactory::createView(const Mantid::Kernel::V3D& position) const
     {
-      return this->createViewAtPoint(position, m_peakRadius);
-    }
-
-    boost::shared_ptr<PeakOverlayView> PeakOverlayFactory::createViewAtPoint(const Mantid::Kernel::V3D& position, const double& radius) const
-    {
-      return boost::make_shared<PeakOverlay>(m_plot, m_parent, position, radius);
+      return boost::make_shared<PeakOverlay>(m_plot, m_parent, position, this->m_peakRadius);
     }
 
     std::string PeakOverlayFactory::getPlotXLabel() const

Code/Mantid/MantidQt/SliceViewer/src/SliceViewer.cpp

@@ -96,7 +96,10 @@ SliceViewer::SliceViewer(QWidget *parent)
       m_dimX(0), m_dimY(1),
       m_logColor(false),
       m_fastRender(true),
-      m_rebinMode(false), m_rebinLocked(true), m_peaksPresenter(PeaksPresenter_sptr(new NullPeaksPresenter))
+      m_rebinMode(false), 
+      m_rebinLocked(true), 
+      m_peaksPresenter(PeaksPresenter_sptr(new NullPeaksPresenter)),
+      m_peaksSliderWidget(NULL)
 {
 	ui.setupUi(this);
 
@@ -1371,7 +1374,6 @@ void SliceViewer::updateDisplay(bool resetAxes)
   m_dimY = 1;
   std::vector<coord_t> slicePoint;
 
-  //DimensionSliceWidget * widget
   for (size_t d=0; d<m_ws->getNumDims(); d++)
   {
     DimensionSliceWidget * widget = m_dimWidgets[d];
@@ -1399,6 +1401,12 @@ void SliceViewer::updateDisplay(bool resetAxes)
   {
     this->resetAxis(m_spect->xAxis(), m_X );
     this->resetAxis(m_spect->yAxis(), m_Y );
+
+    // The dimensionality has changed. It might no longer be possible to plot peaks.
+    enablePeakOverlaysIfAppropriate(); 
+
+    // Transform the peak overlays according to the new plotting.
+    m_peaksPresenter->changeShownDim();
   }
 
   // Set the color range
@@ -1426,8 +1434,11 @@ void SliceViewer::updateDisplay(bool resetAxes)
   m_spect->itemChanged();
   m_plot->replot();
 
-  /// Update the peak positions.
-  this->updatePeaksWithSlicePoint();
+  /// Update the peak positions if peak relevant slider has changed.
+  if(m_peaksSliderWidget != NULL)
+  {
+    m_peaksPresenter->updateWithSlicePoint(m_peaksSliderWidget->getSlicePoint()); 
+  }
 
   // Send out a signal
   emit changedSlicePoint(m_slicePoint);
@@ -1471,14 +1482,8 @@ void SliceViewer::changedShownDim(int index, int dim, int oldDim)
       }
     }
   }
-
-
   // Show the new slice. This finds m_dimX and m_dimY
   this->updateDisplay();  
-  // The dimensionality has changed. It might no longer be possible to plot peaks. We need updateDisplay called first, because we read axis off the plot.
-  enablePeakOverlaysIfAppropriate(); 
-  // Transform the peak overlays according to the new plotting.
-  m_peaksPresenter->changeShownDim();
   // Send out a signal
   emit changedShownDim(m_dimX, m_dimY);
 }
@@ -2098,7 +2103,7 @@ void SliceViewer::peakOverlay_toggled(bool checked)
         IPeaksWorkspace_sptr peaksWS = AnalysisDataService::Instance().retrieveWS<IPeaksWorkspace>(list.front().toStdString());
         PeakOverlayFactory* factory  = new PeakOverlayFactory(m_plot, m_plot->canvas());
         m_peaksPresenter = PeaksPresenter_sptr(new ConcretePeaksPresenter(factory, peaksWS));
-        updatePeaksWithSlicePoint();
+        updatePeakOverlaySliderWidget();
       }
     }
   }
@@ -2109,10 +2114,9 @@ void SliceViewer::peakOverlay_toggled(bool checked)
 }
 
 /**
-Update the peaks overlay with a slice point.
-Find the relevant dimension slider and then use the slice point from that slider.
+Obtain the reference to a new PeakOverlay slider widget if necessary.
 */
-void SliceViewer::updatePeaksWithSlicePoint()
+void SliceViewer::updatePeakOverlaySliderWidget()
 {
   for (size_t d=0; d< m_ws->getNumDims(); d++)
   {
@@ -2121,7 +2125,8 @@ void SliceViewer::updatePeaksWithSlicePoint()
     {
       if(m_peaksPresenter->isLabelOfFreeAxis(widget->getDimName()))
       {
-        m_peaksPresenter->updateWithSlicePoint(widget->getSlicePoint()); 
+        m_peaksSliderWidget = widget; // Cache the widget being used for this.
+        m_peaksPresenter->updateWithSlicePoint(m_peaksSliderWidget->getSlicePoint()); // Ensure that the presenter is up-to-date with the change
       }
     }
   }