PolFilter: internally, store Bloch vector

Device/Pol/PolFilter.cpp

@@ -17,21 +17,13 @@
 #include "Base/Util/Assert.h"
 
 PolFilter::PolFilter(R3 direction, double efficiency, double transmission)
+    : m_vecBloch(direction * efficiency)
+    , m_transmission(transmission)
 {
-    ASSERT(transmission == 0.5);
-    double aplus = transmission * (1.0 + efficiency);
-    double amin = transmission * (1.0 - efficiency);
-    if (aplus < 0.0 || aplus > 1.0 || amin < 0.0 || amin > 1.0)
-        throw std::runtime_error("Invalid efficiency and transmission for polarization analyzer");
-    if (efficiency == 0.0 || transmission == 0.0 || direction.mag() == 0.0) {
-        m_direction = {};
-        m_efficiency = 0;
-        m_transmission = transmission;
-    } else {
-        m_direction = direction.unit_or_throw();
-        m_efficiency = efficiency;
-        m_transmission = transmission;
-    }
+    if (m_transmission < 0 || m_transmission > 0.5)
+        throw std::runtime_error("Invalid polarizer transmission");
+    if (m_vecBloch.mag2() > 1)
+        throw std::runtime_error("Invalid polarizer Bloch vector");
 }
 
 PolFilter::PolFilter()
@@ -41,20 +33,17 @@ PolFilter::PolFilter()
 
 SpinMatrix PolFilter::matrix() const
 {
-    if (m_direction.mag() == 0.0 || m_efficiency == 0.0)
-        return m_transmission * SpinMatrix::One();
-    R3 v = m_direction.unit_or_throw() * m_efficiency;
-    return 2 * m_transmission * SpinMatrix::FromBlochVector(v);
+    return 2 * m_transmission * SpinMatrix::FromBlochVector(m_vecBloch);
 }
 
 R3 PolFilter::analyzerDirection() const
 {
-    return m_direction;
+    return m_vecBloch.unit_or_null();
 }
 
 double PolFilter::analyzerEfficiency() const
 {
-    return m_efficiency;
+    return m_vecBloch.mag();
 }
 
 double PolFilter::transmission() const

Device/Pol/PolFilter.h

@@ -43,8 +43,7 @@ public:
     double transmission() const;
 
 private:
-    R3 m_direction;        //!< direction of polarization analysis
-    double m_efficiency;   //!< efficiency of polarization analysis
+    R3 m_vecBloch;         //!< Bloch vector (efficiency * polarization_direction)
     double m_transmission; //!< transmission of unpolarized beam
 };