text: /*=========================================================================
   *
   *  Copyright Insight Software Consortium
   *
   *  Licensed under the Apache License, Version 2.0 (the "License");
   *  you may not use this file except in compliance with the License.
   *  You may obtain a copy of the License at
   *
   *         http://www.apache.org/licenses/LICENSE-2.0.txt
   *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS,
   *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   *
   *=========================================================================*/
  
  
  #include "itkFEMSolver.h"
  #include "itkFEMSpatialObjectReader.h"
  #include "itkFEMSpatialObjectWriter.h"
  
  int itkFEMLoadGravConstTest(int argc, char *argv[])
  {
    if(argc < 1)
      {
      std::cerr << "Missing Spatial Object Filename" << std::endl;
      return EXIT_FAILURE;
      }
    //Need to register default FEM object types,
    //and setup SpatialReader to recognize FEM types
    //which is all currently done as a HACK in
    //the initializaiton of the itk::FEMFactoryBase::GetFactory()
    itk::FEMFactoryBase::GetFactory()->RegisterDefaultTypes();
  
    typedef itk::fem::Solver<2> Solver2DType;
    Solver2DType::Pointer solver = Solver2DType::New();
  
    typedef itk::FEMSpatialObjectReader<2>      FEMSpatialObjectReaderType;
    typedef FEMSpatialObjectReaderType::Pointer FEMSpatialObjectReaderPointer;
    FEMSpatialObjectReaderPointer SpatialReader = FEMSpatialObjectReaderType::New();
    SpatialReader->SetFileName( argv[1] );
    SpatialReader->Update();
  
    FEMSpatialObjectReaderType::ScenePointer myScene = SpatialReader->GetScene();
    if( !myScene )
      {
      std::cout << "No Scene : [FAILED]" << std::endl;
      return EXIT_FAILURE;
      }
    std::cout << " [PASSED]" << std::endl;
  
    // Testing the fe mesh validity
    typedef itk::FEMObjectSpatialObject<2>      FEMObjectSpatialObjectType;
  
    FEMObjectSpatialObjectType::ChildrenListType* children = SpatialReader->GetGroup()->GetChildren();
    if( strcmp( (*(children->begin() ) )->GetTypeName(), "FEMObjectSpatialObject") )
      {
      std::cout << " [FAILED]" << std::endl;
      return EXIT_FAILURE;
      }
  
    FEMObjectSpatialObjectType::Pointer femSO =
      dynamic_cast<FEMObjectSpatialObjectType *>( (*(children->begin() ) ).GetPointer() );
    if (!femSO)
      {
      std::cout << " dynamic_cast [FAILED]" << std::endl;
      return EXIT_FAILURE;
      }
  
    delete children;
    femSO->GetFEMObject()->FinalizeMesh();
  
    solver->SetInput( femSO->GetFEMObject() );
    solver->Update();
  
    int               numDOF = femSO->GetFEMObject()->GetNumberOfDegreesOfFreedom();
    vnl_vector<float> soln(numDOF);
    for( int i = 0; i < numDOF; i++ )
      {
      soln[i] = solver->GetSolution(i);
      std::cout << "Solution[" << i << "]:" << soln[i] << std::endl;
      }
  
    typedef itk::FEMSpatialObjectWriter<2>      FEMSpatialObjectWriterType;
    typedef FEMSpatialObjectWriterType::Pointer FEMSpatialObjectWriterPointer;
    FEMSpatialObjectWriterPointer SpatialWriter = FEMSpatialObjectWriterType::New();
    SpatialWriter->SetInput(SpatialReader->GetScene() );
    SpatialWriter->SetFileName( argv[2] );
    SpatialWriter->Update();
  
    std::cout << "Test PASSED!" << std::endl;
    return EXIT_SUCCESS;
  }
  