Fix construction of emulsion detector

Neutrino/NeutrinoDetDescr/EmulsionGeoModel/src/EmulsionPlates.cxx

@@ -50,7 +50,8 @@ EmulsionPlates::getParameters()
   m_tungstenWidth = platesParameters->platesWidth();
   m_tungstenHeight = platesParameters->platesHeight();
   m_tungstenThickness = platesParameters->platesThickness();
-  m_material = m_materials->getMaterial(platesParameters->platesMaterial());
+  m_absorberMaterial = m_materials->getMaterial(platesParameters->platesMaterial());
+  m_airMaterial = m_materials->gasMaterial();
 
   m_nBasesPerModule = generalParameters->nBasesPerModule();
   m_nModules       = generalParameters->nModules();
@@ -94,7 +95,10 @@ EmulsionPlates::preBuild()
   const GeoBox* platesShape = new GeoBox(0.5*m_width, 0.5*m_height, 0.5*m_thickness);
 
   // GeoLogVol * platesLog = new GeoLogVol(getName(), platesShape, m_materials->gasMaterial());
-  GeoLogVol * platesLog = new GeoLogVol(getName(), platesShape, m_material);
+  GeoLogVol * platesLog = new GeoLogVol(getName(), platesShape, m_airMaterial);
+
+  const GeoBox* absorberShape = new GeoBox(m_tungstenWidth/2, m_tungstenHeight/2, m_tungstenThickness/2);
+  m_absorberVolume = new GeoLogVol(getName()+"_absorber", absorberShape, m_absorberMaterial);
 
   // m_baseboardPos = new GeoTrf::Translate3D(0.0, 0.0, 0.0);
   // m_frontPos     = new GeoTrf::Translate3D(0.0, 0.0, -(m_baseThickness + m_filmThickness)/2);
@@ -106,7 +110,12 @@ EmulsionPlates::preBuild()
 GeoVPhysVol * 
 EmulsionPlates::build(EmulsionIdentifier id)
 {
-  GeoFullPhysVol * plates = new GeoFullPhysVol(m_logVolume); 
+  GeoFullPhysVol * plates = new GeoFullPhysVol(m_logVolume);
+  GeoPhysVol * physAbsorber = new GeoPhysVol(m_absorberVolume);
+  GeoAlignableTransform* absorberTransform = new GeoAlignableTransform( GeoTrf::Translate3D { 0.0, 0.0, m_zShift} );
+  plates->add(absorberTransform);
+  plates->add(new GeoNameTag("Absorber"));
+  plates->add(physAbsorber);
   
   int nBases = 0;
   int nBasesTotal = m_nModules * m_nBasesPerModule;
@@ -120,12 +129,18 @@ EmulsionPlates::build(EmulsionIdentifier id)
     for (int base = 0; base < m_nBasesPerModule; base++)
     {
       id.setBase(base);
-      GeoAlignableTransform* theTransform = new GeoAlignableTransform( GeoTrf::Translate3D {0.0, 0.0, m_zShift + m_firstBaseZ + ((m_lastBaseZ - m_firstBaseZ)/(nBasesTotal-1))*nBases++} );
-      plates->add(theTransform);
-      plates->add(new GeoNameTag("Base#"+intToString(module*100 + base)));
-      plates->add(new GeoIdentifierTag(module*100 + base));
+      // GeoAlignableTransform* theTransform = new GeoAlignableTransform( GeoTrf::Translate3D {0.0, 0.0, m_zShift + m_firstBaseZ + ((m_lastBaseZ - m_firstBaseZ)/(nBasesTotal-1))*nBases++} );
+      // plates->add(theTransform);
+      // plates->add(new GeoNameTag("Base#"+intToString(module*100 + base)));
+      // plates->add(new GeoIdentifierTag(module*100 + base));
+      // GeoVPhysVol* physBase = m_base->build(id);
+      // plates->add(physBase);
+      GeoAlignableTransform* theTransform = new GeoAlignableTransform( GeoTrf::Translate3D {0.0, 0.0, m_firstBaseZ + ((m_lastBaseZ - m_firstBaseZ)/(nBasesTotal-1))*nBases++} );
+      physAbsorber->add(theTransform);
+      physAbsorber->add(new GeoNameTag("Base#"+intToString(module*100 + base)));
+      physAbsorber->add(new GeoIdentifierTag(module*100 + base));
       GeoVPhysVol* physBase = m_base->build(id);
-      plates->add(physBase);
+      physAbsorber->add(physBase);
       m_detectorManager->addAlignableTransform(1, id.getFilmId(), theTransform, physBase);
     }
     m_detectorManager->numerology().useModule(module);