refs #8992. Utilise coord trans to original.

This has been prevented thus far, because use of coord transforms has been based on the presence of original workspaces. Original workspaces will not be present upon a reload.

I've also exposed the new getters on MDGeometry to python.

Code/Mantid/Framework/API/inc/MantidAPI/MDGeometry.h

@@ -92,6 +92,9 @@ namespace API
 
     void transformDimensions(std::vector<double> & scaling, std::vector<double> & offset);
 
+    size_t getNumberTransformsToOriginal() const;
+    size_t getNumberTransformsFromOriginal() const;
+
     // --------------------------------------------------------------------------------------------
     ///@return the vector of the origin (in the original workspace) that corresponds to 0,0,0... in this workspace
     Mantid::Kernel::VMD & getOrigin()

Code/Mantid/Framework/API/src/MDGeometry.cpp

@@ -512,6 +512,24 @@ namespace API
     return xmlBuilder.create();
   }
 
+  /**
+   * Get the number of transforms defined to the original coordinate system.
+   * @return The number of transforms.
+   */
+  size_t MDGeometry::getNumberTransformsToOriginal() const
+  {
+    return m_transforms_ToOriginal.size();
+  }
+
+  /**
+   * Get the number of transforms defined from the original coordinate system.
+   * @return The number of transforms.
+   */
+  size_t MDGeometry::getNumberTransformsFromOriginal() const
+  {
+    return m_transforms_FromOriginal.size();
+  }
+
 
 } // namespace Mantid
 } // namespace API

Code/Mantid/Framework/API/test/MDGeometryTest.h

@@ -207,8 +207,22 @@ class MDGeometryTest : public CxxTest::TestSuite
     AnalysisDataService::Instance().remove("MDGeometryTest_originalWS");
     TSM_ASSERT("Original workspace reference was deleted.", !g.hasOriginalWorkspace());
     TSM_ASSERT("Original workspace reference is cleared.", !g.getOriginalWorkspace());
+  }
 
+  void test_transforms_to_original()
+  {
+    MDGeometry g;
+    g.setTransformFromOriginal(new NullCoordTransform, 0);
+    g.setTransformFromOriginal(new NullCoordTransform, 1);
+    TSM_ASSERT_EQUALS("Wrong number of transforms from original reported.", 2, g.getNumberTransformsFromOriginal());
+  }
 
+  void test_transforms_from_original()
+  {
+    MDGeometry g;
+    g.setTransformToOriginal(new NullCoordTransform, 0);
+    g.setTransformToOriginal(new NullCoordTransform, 1);
+    TSM_ASSERT_EQUALS("Wrong number of transforms to original reported.", 2, g.getNumberTransformsToOriginal());
   }
 
 

Code/Mantid/Framework/MDEvents/src/QueryMDWorkspace.cpp

@@ -264,7 +264,7 @@ namespace MDEvents
       output->cell<double>(rowCounter, cellIndex++) = it->getNormalizedError();
       output->cell<int>(rowCounter, cellIndex++) = int(it->getNumEvents());
       VMD center = it->getCenter();
-      const size_t numberOriginal = input->numOriginalWorkspaces();
+      const size_t numberOriginal = input->getNumberTransformsToOriginal();
       if(numberOriginal > 0)
       {
         const size_t index = numberOriginal -1;

Code/Mantid/Framework/PythonInterface/mantid/api/src/Exports/MDGeometry.cpp

@@ -90,6 +90,13 @@ void export_MDGeometry()
     .def("getOrigin", (const Mantid::Kernel::VMD & (MDGeometry::*)() const)&MDGeometry::getOrigin,
          return_value_policy<copy_const_reference>(),
          "Returns the vector of the origin (in the original workspace) that corresponds to 0,0,0... in this workspace")
+
+    .def("getNumberTransformsFromOriginal", &MDGeometry::getNumberTransformsFromOriginal,
+        "Returns the number of transformations from original workspace coordinate systems")
+
+    .def("getNumberTransformsToOriginal", &MDGeometry::getNumberTransformsToOriginal,
+        "Returns the number of transformations to original workspace coordinate systems")
+
     ;
 }
 

Code/Mantid/MantidQt/API/src/MantidQwtIMDWorkspaceData.cpp

@@ -325,21 +325,32 @@ void MantidQwtIMDWorkspaceData::setPreviewMode(bool preview)
 {
   m_preview = preview;
   // If the workspace has no original, then we MUST be in preview mode.
-  if (preview || (m_workspace->numOriginalWorkspaces() == 0))
+  const size_t nOriginalWorkspaces = m_workspace->numOriginalWorkspaces();
+  if (preview || (nOriginalWorkspaces == 0))
   {
     // Preview mode. No transformation.
     m_originalWorkspace = m_workspace;
-    m_transform = new NullCoordTransform(m_workspace->getNumDims());
   }
   else
   {
     // Refer to the last workspace = the intermediate in the case of MDHisto binning
-    size_t index = m_workspace->numOriginalWorkspaces()-1;
-    m_originalWorkspace = boost::dynamic_pointer_cast<IMDWorkspace>(m_workspace->getOriginalWorkspace(index));
-    CoordTransform * temp = m_workspace->getTransformToOriginal(index);
+    const size_t indexOfWS = nOriginalWorkspaces-1; // Get the last workspace
+    m_originalWorkspace = boost::dynamic_pointer_cast<IMDWorkspace>(m_workspace->getOriginalWorkspace(indexOfWS));
+  }
+
+  const size_t nTransformsToOriginal = m_workspace->getNumberTransformsToOriginal();
+  if (preview || (nTransformsToOriginal == 0))
+  {
+    m_transform = new NullCoordTransform(m_workspace->getNumDims());
+  }
+  else
+  {
+    const size_t indexOfTransform = nTransformsToOriginal-1; // Get the last transform
+    CoordTransform * temp = m_workspace->getTransformToOriginal(indexOfTransform);
     if (temp)
-      m_transform = temp->clone();
+          m_transform = temp->clone();
   }
+
   this->choosePlotAxis();
 }