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//
// $Id: G4GDMLReadStructure.cc,v 1.62 2009/09/24 15:04:34 gcosmo Exp $
// GEANT4 tag $Name: geant4-09-03 $
//
// class G4GDMLReadStructure Implementation
//
// Original author: Zoltan Torzsok, November 2007
//
// --------------------------------------------------------------------

#include "G4GDMLReadStructure.hh"

#include "G4LogicalVolume.hh"
#include "G4VPhysicalVolume.hh"
#include "G4PVPlacement.hh"
#include "G4LogicalVolumeStore.hh"
#include "G4PhysicalVolumeStore.hh"
#include "G4AssemblyVolume.hh"
#include "G4ReflectionFactory.hh"
#include "G4PVDivisionFactory.hh"
#include "G4LogicalBorderSurface.hh"
#include "G4LogicalSkinSurface.hh"
#include "G4VisAttributes.hh"

G4GDMLReadStructure::G4GDMLReadStructure() : G4GDMLReadParamvol()
{
}

G4GDMLReadStructure::~G4GDMLReadStructure()
{
}

G4GDMLAuxPairType G4GDMLReadStructure::
AuxiliaryRead(const xercesc::DOMElement* const auxiliaryElement)
{
   G4GDMLAuxPairType auxpair;

   const xercesc::DOMNamedNodeMap* const attributes
         = auxiliaryElement->getAttributes();
   XMLSize_t attributeCount = attributes->getLength();

   for (XMLSize_t attribute_index=0;
        attribute_index<attributeCount; attribute_index++)
   {
      xercesc::DOMNode* attribute_node = attributes->item(attribute_index);

      if (attribute_node->getNodeType() != xercesc::DOMNode::ATTRIBUTE_NODE)
        { continue; }

      const xercesc::DOMAttr* const attribute
            = dynamic_cast<xercesc::DOMAttr*>(attribute_node);   
      const G4String attName = Transcode(attribute->getName());
      const G4String attValue = Transcode(attribute->getValue());

      if (attName=="auxtype") { auxpair.type = attValue; } else
      if (attName=="auxvalue") { auxpair.value = eval.Evaluate(attValue); }
   }

   return auxpair;
}

void G4GDMLReadStructure::
BorderSurfaceRead(const xercesc::DOMElement* const bordersurfaceElement)
{
   G4String name;
   G4VPhysicalVolume* pv1 = 0;
   G4VPhysicalVolume* pv2 = 0;
   G4SurfaceProperty* prop = 0;
   G4int index = 0;

   const xercesc::DOMNamedNodeMap* const attributes
         = bordersurfaceElement->getAttributes();
   XMLSize_t attributeCount = attributes->getLength();

   for (XMLSize_t attribute_index=0;
        attribute_index<attributeCount; attribute_index++)
   {
      xercesc::DOMNode* attribute_node = attributes->item(attribute_index);

      if (attribute_node->getNodeType() != xercesc::DOMNode::ATTRIBUTE_NODE)
        { continue; }

      const xercesc::DOMAttr* const attribute
            = dynamic_cast<xercesc::DOMAttr*>(attribute_node);   
      const G4String attName = Transcode(attribute->getName());
      const G4String attValue = Transcode(attribute->getValue());

      if (attName=="name")
        { name = GenerateName(attValue); } else
      if (attName=="surfaceproperty")
        { prop = GetSurfaceProperty(GenerateName(attValue)); }
   }

   for (xercesc::DOMNode* iter = bordersurfaceElement->getFirstChild();
        iter != 0; iter = iter->getNextSibling())
   {
      if (iter->getNodeType() != xercesc::DOMNode::ELEMENT_NODE)  { continue; }

      const xercesc::DOMElement* const child
            = dynamic_cast<xercesc::DOMElement*>(iter);
      const G4String tag = Transcode(child->getTagName());

      if (tag != "physvolref")  { continue; }
 
      if (index==0)
        { pv1 = GetPhysvol(GenerateName(RefRead(child))); index++; } else
      if (index==1)
        { pv2 = GetPhysvol(GenerateName(RefRead(child))); index++; } else
      break;
   }

   new G4LogicalBorderSurface(Strip(name),pv1,pv2,prop);
}

void G4GDMLReadStructure::
DivisionvolRead(const xercesc::DOMElement* const divisionvolElement)
{
   G4String name;
   G4double unit = 1.0;
   G4double width = 0.0;
   G4double offset = 0.0;
   G4int number = 0;
   EAxis axis = kUndefined;
   G4LogicalVolume* logvol = 0;
   
   const xercesc::DOMNamedNodeMap* const attributes
         = divisionvolElement->getAttributes();
   XMLSize_t attributeCount = attributes->getLength();

   for (XMLSize_t attribute_index=0;
        attribute_index<attributeCount; attribute_index++)
   {
      xercesc::DOMNode* attribute_node = attributes->item(attribute_index);

      if (attribute_node->getNodeType() != xercesc::DOMNode::ATTRIBUTE_NODE)
        { continue; }

      const xercesc::DOMAttr* const attribute
            = dynamic_cast<xercesc::DOMAttr*>(attribute_node);   
      const G4String attName = Transcode(attribute->getName());
      const G4String attValue = Transcode(attribute->getValue());

      if (attName=="name") { name = attValue; } else
      if (attName=="unit") { unit = eval.Evaluate(attValue); } else
      if (attName=="width") { width = eval.Evaluate(attValue); } else
      if (attName=="offset") { offset = eval.Evaluate(attValue); } else
      if (attName=="number") { number = eval.EvaluateInteger(attValue); } else
      if (attName=="axis")
      {
         if (attValue=="kXAxis") { axis = kXAxis; } else
         if (attValue=="kYAxis") { axis = kYAxis; } else
         if (attValue=="kZAxis") { axis = kZAxis; } else
         if (attValue=="kRho") { axis = kRho; } else
         if (attValue=="kPhi") { axis = kPhi; }
      }
   }

   width *= unit;
   offset *= unit;

   for (xercesc::DOMNode* iter = divisionvolElement->getFirstChild();
        iter != 0;iter = iter->getNextSibling())
   {
      if (iter->getNodeType() != xercesc::DOMNode::ELEMENT_NODE) { continue; }

      const xercesc::DOMElement* const child
            = dynamic_cast<xercesc::DOMElement*>(iter);
      const G4String tag = Transcode(child->getTagName());

      if (tag=="volumeref") { logvol = GetVolume(GenerateName(RefRead(child))); }
   }

   G4PVDivisionFactory::GetInstance();
   G4PhysicalVolumesPair pair;

   G4String pv_name = logvol->GetName() + "_div";
   if ((number != 0) && (width == 0.0))
   {
     pair = G4ReflectionFactory::Instance()
            ->Divide(pv_name,logvol,pMotherLogical,axis,number,offset);
   }
   else if ((number == 0) && (width != 0.0))
   {
     pair = G4ReflectionFactory::Instance()
            ->Divide(pv_name,logvol,pMotherLogical,axis,width,offset);
   }
   else
   {
     pair = G4ReflectionFactory::Instance()
            ->Divide(pv_name,logvol,pMotherLogical,axis,number,width,offset);
   }

   if (pair.first != 0) { GeneratePhysvolName(name,pair.first); }
   if (pair.second != 0) { GeneratePhysvolName(name,pair.second); }
}

G4LogicalVolume* G4GDMLReadStructure::
FileRead(const xercesc::DOMElement* const fileElement)
{
   G4String name;
   G4String volname;

   const xercesc::DOMNamedNodeMap* const attributes
         = fileElement->getAttributes();
   XMLSize_t attributeCount = attributes->getLength();

   for (XMLSize_t attribute_index=0;
        attribute_index<attributeCount; attribute_index++)
   {
      xercesc::DOMNode* attribute_node = attributes->item(attribute_index);

      if (attribute_node->getNodeType() != xercesc::DOMNode::ATTRIBUTE_NODE)
        { continue; }

      const xercesc::DOMAttr* const attribute
            = dynamic_cast<xercesc::DOMAttr*>(attribute_node);   
      const G4String attName = Transcode(attribute->getName());
      const G4String attValue = Transcode(attribute->getValue());

      if (attName=="name") { name = attValue; } else
      if (attName=="volname") { volname = attValue; }
   }

   const G4bool isModule = true;
   G4GDMLReadStructure structure;
   structure.Read(name,validate,isModule);

   // Register existing auxiliar information defined in child module
   //
   const G4GDMLAuxMapType* aux = structure.GetAuxMap();
   if (!aux->empty())
   {
     G4GDMLAuxMapType::const_iterator pos;
     for (pos = aux->begin(); pos != aux->end(); ++pos)
     {
       auxMap.insert(std::make_pair(pos->first,pos->second));
     }
   }

   // Return volume structure from child module
   //
   if (volname.empty())
   {
     return structure.GetVolume(structure.GetSetup("Default"));
   }
   else
   {
     return structure.GetVolume(structure.GenerateName(volname));
   }
}

void G4GDMLReadStructure::
PhysvolRead(const xercesc::DOMElement* const physvolElement,
            G4AssemblyVolume* pAssembly)
{
   G4String name;
   G4LogicalVolume* logvol = 0;
   G4AssemblyVolume* assembly = 0;
   G4ThreeVector position(0.0,0.0,0.0);
   G4ThreeVector rotation(0.0,0.0,0.0);
   G4ThreeVector scale(1.0,1.0,1.0);

   const xercesc::DOMNamedNodeMap* const attributes
         = physvolElement->getAttributes();
   XMLSize_t attributeCount = attributes->getLength();

   for (XMLSize_t attribute_index=0;
        attribute_index<attributeCount; attribute_index++)
   {
     xercesc::DOMNode* attribute_node = attributes->item(attribute_index);

     if (attribute_node->getNodeType() != xercesc::DOMNode::ATTRIBUTE_NODE)
       { continue; }

     const xercesc::DOMAttr* const attribute
           = dynamic_cast<xercesc::DOMAttr*>(attribute_node);   
     const G4String attName = Transcode(attribute->getName());
     const G4String attValue = Transcode(attribute->getValue());

     if (attName=="name") { name = attValue; }
   }

   for (xercesc::DOMNode* iter = physvolElement->getFirstChild();
        iter != 0; iter = iter->getNextSibling())
   {
     if (iter->getNodeType() != xercesc::DOMNode::ELEMENT_NODE)  { continue; }

     const xercesc::DOMElement* const child
           = dynamic_cast<xercesc::DOMElement*>(iter);
     const G4String tag = Transcode(child->getTagName());

     if (tag=="volumeref")
       {
         const G4String& child_name = GenerateName(RefRead(child));
         assembly = GetAssembly(child_name);
         if (!assembly) { logvol = GetVolume(child_name); }
       }
     else if (tag=="file")
       { logvol = FileRead(child); }
     else if (tag=="position")
       { VectorRead(child,position); }
     else if (tag=="rotation")
       { VectorRead(child,rotation); }
     else if (tag=="scale")
       { VectorRead(child,scale); }
     else if (tag=="positionref")
       { position = GetPosition(GenerateName(RefRead(child))); }
     else if (tag=="rotationref")
        { rotation = GetRotation(GenerateName(RefRead(child))); }
     else if (tag=="scaleref")
        { scale = GetScale(GenerateName(RefRead(child))); }
     else
        {
          G4String error_msg = "Unknown tag in physvol: " + tag;
          G4Exception("G4GDMLReadStructure::PhysvolRead()", "ReadError",
                      FatalException, error_msg);
        }
   }

   G4Transform3D transform(GetRotationMatrix(rotation).inverse(),position);
   transform = transform*G4Scale3D(scale.x(),scale.y(),scale.z());

   if (pAssembly)   // Fill assembly structure
   {
     pAssembly->AddPlacedVolume(logvol, transform);
   }
   else             // Generate physical volume tree or do assembly imprint
   {
     if (assembly)
     {
       assembly->MakeImprint(pMotherLogical, transform, 0, check);
     }
     else
     {
       G4String pv_name = logvol->GetName() + "_PV";
       G4PhysicalVolumesPair pair = G4ReflectionFactory::Instance()
         ->Place(transform,pv_name,logvol,pMotherLogical,false,0,check);

       if (pair.first != 0) { GeneratePhysvolName(name,pair.first); }
       if (pair.second != 0) { GeneratePhysvolName(name,pair.second); }
     }
   }
}

void G4GDMLReadStructure::
ReplicavolRead(const xercesc::DOMElement* const replicavolElement, G4int number)
{
  G4LogicalVolume* logvol = 0;
  for (xercesc::DOMNode* iter = replicavolElement->getFirstChild();
                         iter != 0; iter = iter->getNextSibling())
  {
    if (iter->getNodeType() != xercesc::DOMNode::ELEMENT_NODE)  { continue; }

    const xercesc::DOMElement* const child
          = dynamic_cast<xercesc::DOMElement*>(iter);
    const G4String tag = Transcode(child->getTagName());

    if (tag=="volumeref")
    {
      logvol = GetVolume(GenerateName(RefRead(child)));
    }
    else if (tag=="replicate_along_axis")
    {
      ReplicaRead(child,logvol,number);
    }
    else
    {
      G4String error_msg = "Unknown tag in ReplicavolRead: " + tag;
      G4Exception("G4GDMLReadStructure::ReplicavolRead()",
                  "ReadError", FatalException, error_msg);
    }
  }
}

void G4GDMLReadStructure::
ReplicaRead(const xercesc::DOMElement* const replicaElement,
            G4LogicalVolume* logvol, G4int number)
{
   G4double width = 0.0;
   G4double offset = 0.0;
   G4ThreeVector position(0.0,0.0,0.0);
   G4ThreeVector rotation(0.0,0.0,0.0);
   EAxis axis = kUndefined;
   G4String name;
 
   for (xercesc::DOMNode* iter = replicaElement->getFirstChild();
                          iter != 0; iter = iter->getNextSibling())
   {
      if (iter->getNodeType() != xercesc::DOMNode::ELEMENT_NODE)  { continue; }

      const xercesc::DOMElement* const child
            = dynamic_cast<xercesc::DOMElement*>(iter);
      const G4String tag = Transcode(child->getTagName()); 

      if (tag=="position")
        { VectorRead(child,position); } else
      if (tag=="rotation")
        { VectorRead(child,rotation); } else
      if (tag=="positionref")
        { position = GetPosition(GenerateName(RefRead(child))); } else
      if (tag=="rotationref")
        { rotation = GetRotation(GenerateName(RefRead(child))); } else
      if (tag=="direction")
        { axis=AxisRead(child); } else
      if (tag=="width")
        { width=QuantityRead(child); } else
      if (tag=="offset")
        { offset=QuantityRead(child); }
      else
      {
        G4String error_msg = "Unknown tag in ReplicaRead: " + tag;
        G4Exception("G4GDMLReadStructure::ReplicaRead()", "ReadError",
                    FatalException, error_msg);
      }
   }

   G4String pv_name = logvol->GetName() + "_PV";
   G4PhysicalVolumesPair pair = G4ReflectionFactory::Instance()
     ->Replicate(pv_name,logvol,pMotherLogical,axis,number,width,offset);

   if (pair.first != 0) { GeneratePhysvolName(name,pair.first); }
   if (pair.second != 0) { GeneratePhysvolName(name,pair.second); }

}

EAxis G4GDMLReadStructure::
AxisRead(const xercesc::DOMElement* const axisElement)
{
   
   EAxis axis = kUndefined;

   const xercesc::DOMNamedNodeMap* const attributes
         = axisElement->getAttributes();
   XMLSize_t attributeCount = attributes->getLength();

   for (XMLSize_t attribute_index=0;
        attribute_index<attributeCount; attribute_index++)
   {
      xercesc::DOMNode* attribute_node = attributes->item(attribute_index);

      if (attribute_node->getNodeType() != xercesc::DOMNode::ATTRIBUTE_NODE)
        { continue; }

      const xercesc::DOMAttr* const attribute
            = dynamic_cast<xercesc::DOMAttr*>(attribute_node);   
      const G4String attName = Transcode(attribute->getName());
      const G4String attValue = Transcode(attribute->getValue());
      if (attName=="x")
        { if( eval.Evaluate(attValue)==1.) {axis=kXAxis;} }
      else if (attName=="y")
        { if( eval.Evaluate(attValue)==1.) {axis=kYAxis;} }
      else if (attName=="z")
        { if( eval.Evaluate(attValue)==1.) {axis=kZAxis;} }
      else if (attName=="rho")
        { if( eval.Evaluate(attValue)==1.) {axis=kRho;}   }
      else if (attName=="phi")
        { if( eval.Evaluate(attValue)==1.) {axis=kPhi;}   }
   }

   return axis;
}

G4double G4GDMLReadStructure::
QuantityRead(const xercesc::DOMElement* const readElement)
{
   G4double value = 0.0;
   G4double unit = 0.0;
   const xercesc::DOMNamedNodeMap* const attributes
         = readElement->getAttributes();
   XMLSize_t attributeCount = attributes->getLength();

   for (XMLSize_t attribute_index=0;
        attribute_index<attributeCount; attribute_index++)
   {
      xercesc::DOMNode* attribute_node = attributes->item(attribute_index);

      if (attribute_node->getNodeType() != xercesc::DOMNode::ATTRIBUTE_NODE)
        { continue; }
      const xercesc::DOMAttr* const attribute
            = dynamic_cast<xercesc::DOMAttr*>(attribute_node);   
      const G4String attName = Transcode(attribute->getName());
      const G4String attValue = Transcode(attribute->getValue());

      if (attName=="unit") { unit = eval.Evaluate(attValue); } else
      if (attName=="value"){ value= eval.Evaluate(attValue); } 
   }

   return value*unit;
}

void G4GDMLReadStructure::
VolumeRead(const xercesc::DOMElement* const volumeElement)
{
   G4VSolid* solidPtr = 0;
   G4Material* materialPtr = 0;
   G4GDMLAuxListType auxList;
   
   XMLCh *name_attr = xercesc::XMLString::transcode("name");
   const G4String name = Transcode(volumeElement->getAttribute(name_attr));
   xercesc::XMLString::release(&name_attr);

   for (xercesc::DOMNode* iter = volumeElement->getFirstChild();
        iter != 0; iter = iter->getNextSibling())
   {
      if (iter->getNodeType() != xercesc::DOMNode::ELEMENT_NODE)  { continue; }

      const xercesc::DOMElement* const child
            = dynamic_cast<xercesc::DOMElement*>(iter);
      const G4String tag = Transcode(child->getTagName());

      if (tag=="auxiliary")
        { auxList.push_back(AuxiliaryRead(child)); } else
      if (tag=="materialref")
        { materialPtr = GetMaterial(GenerateName(RefRead(child),true)); } else
      if (tag=="solidref")
        { solidPtr = GetSolid(GenerateName(RefRead(child))); }
   }

   pMotherLogical = new G4LogicalVolume(solidPtr,materialPtr,
                                        GenerateName(name),0,0,0);

   if (!auxList.empty()) { auxMap[pMotherLogical] = auxList; }

   Volume_contentRead(volumeElement);
}

void G4GDMLReadStructure::
AssemblyRead(const xercesc::DOMElement* const assemblyElement)
{
   XMLCh *name_attr = xercesc::XMLString::transcode("name");
   const G4String name = Transcode(assemblyElement->getAttribute(name_attr));
   xercesc::XMLString::release(&name_attr);

   G4AssemblyVolume* pAssembly = new G4AssemblyVolume();
   assemblyMap.insert(std::make_pair(GenerateName(name), pAssembly));

   for (xercesc::DOMNode* iter = assemblyElement->getFirstChild();
        iter != 0; iter = iter->getNextSibling())
   {
      if (iter->getNodeType() != xercesc::DOMNode::ELEMENT_NODE) { continue; }
      const xercesc::DOMElement* const child
            = dynamic_cast<xercesc::DOMElement*>(iter);
      const G4String tag = Transcode(child->getTagName());

      if (tag=="physvol")
      {
        PhysvolRead(child, pAssembly);
      }
      else
      {
        G4cout << "Unsupported GDML tag '" << tag
               << "' for Geant4 assembly structure !" << G4endl;
      }
   }
}

void G4GDMLReadStructure::
SkinSurfaceRead(const xercesc::DOMElement* const skinsurfaceElement)
{
   G4String name;
   G4LogicalVolume* logvol = 0;
   G4SurfaceProperty* prop = 0;

   const xercesc::DOMNamedNodeMap* const attributes
         = skinsurfaceElement->getAttributes();
   XMLSize_t attributeCount = attributes->getLength();

   for (XMLSize_t attribute_index=0;
        attribute_index<attributeCount; attribute_index++)
   {
      xercesc::DOMNode* attribute_node = attributes->item(attribute_index);

      if (attribute_node->getNodeType() != xercesc::DOMNode::ATTRIBUTE_NODE)
        { continue; }

      const xercesc::DOMAttr* const attribute
            = dynamic_cast<xercesc::DOMAttr*>(attribute_node);   
      const G4String attName = Transcode(attribute->getName());
      const G4String attValue = Transcode(attribute->getValue());

      if (attName=="name")
        { name = GenerateName(attValue); } else
      if (attName=="surfaceproperty")
        { prop = GetSurfaceProperty(GenerateName(attValue)); }
   }

   for (xercesc::DOMNode* iter = skinsurfaceElement->getFirstChild();
        iter != 0; iter = iter->getNextSibling())
   {
      if (iter->getNodeType() != xercesc::DOMNode::ELEMENT_NODE)  { continue; }

      const xercesc::DOMElement* const child
            = dynamic_cast<xercesc::DOMElement*>(iter);
      const G4String tag = Transcode(child->getTagName());

      if (tag=="volumeref")
      {
        logvol = GetVolume(GenerateName(RefRead(child)));
      }
      else
      {
        G4String error_msg = "Unknown tag in skinsurface: " + tag;
        G4Exception("G4GDMLReadStructure::SkinsurfaceRead()", "ReadError",
                    FatalException, error_msg);
      }
   }

   new G4LogicalSkinSurface(Strip(name),logvol,prop);
}

void G4GDMLReadStructure::
Volume_contentRead(const xercesc::DOMElement* const volumeElement)
{
   for (xercesc::DOMNode* iter = volumeElement->getFirstChild();
        iter != 0; iter = iter->getNextSibling())
   {
      if (iter->getNodeType() != xercesc::DOMNode::ELEMENT_NODE) { continue; }

      const xercesc::DOMElement* const child
            = dynamic_cast<xercesc::DOMElement*>(iter);
      const G4String tag = Transcode(child->getTagName());

      if ((tag=="auxiliary") || (tag=="materialref") || (tag=="solidref"))
      {
        // These are already processed in VolumeRead()
      }
      else if (tag=="paramvol")
      {
        ParamvolRead(child,pMotherLogical);
      }
      else if (tag=="physvol")
      {
        PhysvolRead(child);
      }
      else if (tag=="replicavol")
      {
        G4int number = 1;
        const xercesc::DOMNamedNodeMap* const attributes
              = child->getAttributes();
        XMLSize_t attributeCount = attributes->getLength();
        for (XMLSize_t attribute_index=0;
                       attribute_index<attributeCount; attribute_index++)
        {
          xercesc::DOMNode* attribute_node
                 = attributes->item(attribute_index);
          if (attribute_node->getNodeType()!=xercesc::DOMNode::ATTRIBUTE_NODE)
          {
            continue;
          }
          const xercesc::DOMAttr* const attribute
                = dynamic_cast<xercesc::DOMAttr*>(attribute_node);   
          const G4String attName = Transcode(attribute->getName());
          const G4String attValue = Transcode(attribute->getValue());
          if (attName=="number")
          {
            number = eval.EvaluateInteger(attValue);
          }
        }
        ReplicavolRead(child,number); 
      }
      else if (tag=="divisionvol")
      {
        DivisionvolRead(child);
      }
      else if (tag=="loop")
      {
        LoopRead(child,&G4GDMLRead::Volume_contentRead);
      }
      else
      {
        G4cout << "Treating unknown GDML tag in volume '" << tag
               << "' as GDML extension..." << G4endl;
      }
   }
}

void G4GDMLReadStructure::
StructureRead(const xercesc::DOMElement* const structureElement)
{
   G4cout << "G4GDML: Reading structure..." << G4endl;

   for (xercesc::DOMNode* iter = structureElement->getFirstChild();
        iter != 0; iter = iter->getNextSibling())
   {
      if (iter->getNodeType() != xercesc::DOMNode::ELEMENT_NODE)  { continue; }

      const xercesc::DOMElement* const child
            = dynamic_cast<xercesc::DOMElement*>(iter);
      const G4String tag = Transcode(child->getTagName());

      if (tag=="bordersurface") { BorderSurfaceRead(child); } else
      if (tag=="skinsurface") { SkinSurfaceRead(child); } else
      if (tag=="volume") { VolumeRead(child); } else
      if (tag=="assembly") { AssemblyRead(child); } else
      if (tag=="loop") { LoopRead(child,&G4GDMLRead::StructureRead); }
      else
      {
        G4String error_msg = "Unknown tag in structure: " + tag;
        G4Exception("G4GDMLReadStructure::StructureRead()",
                    "ReadError", FatalException, error_msg);
      }
   }
}

G4VPhysicalVolume* G4GDMLReadStructure::
GetPhysvol(const G4String& ref) const
{
   G4VPhysicalVolume* physvolPtr =
     G4PhysicalVolumeStore::GetInstance()->GetVolume(ref,false);

   if (!physvolPtr)
   {
     G4String error_msg = "Referenced physvol '" + ref + "' was not found!";
     G4Exception("G4GDMLReadStructure::GetPhysvol()", "ReadError",
                 FatalException, error_msg);
   }

   return physvolPtr;
}

G4LogicalVolume* G4GDMLReadStructure::
GetVolume(const G4String& ref) const
{
   G4LogicalVolume *volumePtr
   = G4LogicalVolumeStore::GetInstance()->GetVolume(ref,false);

   if (!volumePtr)
   {
     G4String error_msg = "Referenced volume '" + ref + "' was not found!";
     G4Exception("G4GDMLReadStructure::GetVolume()", "ReadError",
                 FatalException, error_msg);
   }

   return volumePtr;
}

G4AssemblyVolume* G4GDMLReadStructure::
GetAssembly(const G4String& ref) const
{
   G4GDMLAssemblyMapType::const_iterator pos = assemblyMap.find(ref);
   if (pos != assemblyMap.end()) { return pos->second; }
   return 0;
}

G4GDMLAuxListType G4GDMLReadStructure::
GetVolumeAuxiliaryInformation(const G4LogicalVolume* const logvol)
{
   G4GDMLAuxMapType::const_iterator pos = auxMap.find(logvol);
   if (pos != auxMap.end()) { return pos->second; }
   else { return G4GDMLAuxListType(); }
}

const G4GDMLAuxMapType* G4GDMLReadStructure::
GetAuxMap() const
{
   return &auxMap;
}

G4VPhysicalVolume* G4GDMLReadStructure::
GetWorldVolume(const G4String& setupName)
{    
   G4LogicalVolume* volume = GetVolume(Strip(GetSetup(setupName)));
   volume->SetVisAttributes(G4VisAttributes::Invisible);
   G4VPhysicalVolume* pvWorld =
     new G4PVPlacement(0,G4ThreeVector(0,0,0),volume,setupName,0,0,0);
   return pvWorld;
}
