Added check for need to use polarization analysis (based on the materials used in the sample)

Core/Algorithms/inc/Simulation.h

@@ -130,6 +130,9 @@ class BA_CORE_API_ Simulation : public IParameterized, public ICloneable
     //! Update the sample by calling the sample builder, if present
     void updateSample();
 
+    //! Checks if the sample requires a polarized calculation
+    bool checkPolarizationPresent() const;
+
     // components describing an experiment and its simulation:
     ISample *mp_sample;
     const ISampleBuilder *mp_sample_builder;

Core/Algorithms/src/Simulation.cpp

@@ -19,6 +19,7 @@
 #include "ProgramOptions.h"
 #include "DWBASimulation.h"
 #include "MessageService.h"
+#include "SampleMaterialVisitor.h"
 
 #include <boost/thread.hpp>
 #include <gsl/gsl_errno.h>
@@ -334,6 +335,24 @@ void Simulation::updateSample()
     }
 }
 
+bool Simulation::checkPolarizationPresent() const
+{
+    if (!mp_sample) {
+        throw ClassInitializationException("Simulation::"
+                "checkPolarizationPresent(): sample not initialized");
+    }
+    SampleMaterialVisitor material_vis;
+    mp_sample->accept(&material_vis);
+    std::vector<const IMaterial *> materials = material_vis.getMaterials();
+    for (std::vector<const IMaterial *>::const_iterator it = materials.begin();
+            it != materials.end(); ++it) {
+        if (!(*it)->isScalarMaterial()) {
+            return true;
+        }
+    }
+    return false;
+}
+
 void Simulation::setDetectorParameters(const OutputData<double >& output_data)
 {
     m_instrument.matchDetectorParameters(output_data);

Core/Samples/inc/HomogeneousMagneticMaterial.h

@@ -48,7 +48,7 @@ public:
 
     //! Indicates that the material is not scalar. This means that different
     //! polarization states will be diffracted differently
-    virtual bool isScalarMaterial() { return false; }
+    virtual bool isScalarMaterial() const { return false; }
 
     //! Get the scattering matrix from the refractive index, the
     //! magnetic field and a given wavevector

Core/Samples/inc/IMaterial.h

@@ -40,7 +40,7 @@ public:
     //! Indicates whether the interaction with the material is scalar.
     //! This means that different polarization states will be diffracted
     //! equally
-    virtual bool isScalarMaterial() { return true; }
+    virtual bool isScalarMaterial() const { return true; }
 
     friend std::ostream &operator<<(std::ostream &ostr, const IMaterial &m)
     { m.print(ostr); return ostr; }