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.
   *
   *=========================================================================*/
  
  // Software Guide : BeginLatex
  //
  // \index{itk::SpatialObjectTreeContainer}
  // This example describes how to use the \doxygen{SpatialObjectTreeContainer}
  // to form a hierarchy of SpatialObjects.
  // First we include the appropriate header file.
  // Software Guide : EndLatex
  
  // Software Guide : BeginCodeSnippet
  #include "itkSpatialObjectTreeContainer.h"
  // Software Guide : EndCodeSnippet
  
  #include "itkGroupSpatialObject.h"
  #include "itkLevelOrderTreeIterator.h"
  
  int main( int , char *[] )
  {
    // Software Guide : BeginLatex
    // Next we define the type of node and the type of tree we plan to use.
    // Both are templated over the dimensionality of the space.
    // Let's create a 2-dimensional tree.
    // Software Guide : EndLatex
    // Software Guide : BeginCodeSnippet
    typedef itk::GroupSpatialObject<2> NodeType;
    typedef itk::SpatialObjectTreeContainer<2> TreeType;
    // Software Guide : EndCodeSnippet
  
    // Software Guide : BeginLatex
    // Then, we can create three nodes and set their corresponding identification
    // numbers (using \code{SetId}).
    // Software Guide : EndLatex
    // Software Guide : BeginCodeSnippet
    NodeType::Pointer object0 = NodeType::New();
    object0->SetId(0);
    NodeType::Pointer object1 = NodeType::New();
    object1->SetId(1);
    NodeType::Pointer object2 = NodeType::New();
    object2->SetId(2);
    // Software Guide : EndCodeSnippet
  
    // Software Guide : BeginLatex
    // The hierarchy is formed using the \code{AddSpatialObject()} function.
    // Software Guide : EndLatex
    // Software Guide : BeginCodeSnippet
    object0->AddSpatialObject(object1);
    object1->AddSpatialObject(object2);
    // Software Guide : EndCodeSnippet
  
    // Software Guide : BeginLatex
    // After instantiation of the tree we set its root
    // using the \code{SetRoot()} function.
    // Software Guide : EndLatex
    // Software Guide : BeginCodeSnippet
    TreeType::Pointer tree = TreeType::New();
    tree->SetRoot(object0.GetPointer());
    // Software Guide : EndCodeSnippet
  
    // Software Guide : BeginLatex
    // The tree iterators described in a previous section of this guide can be used to parse the
    // hierarchy. For example, via an \doxygen{LevelOrderTreeIterator} templated over the type of tree,
    // we can parse the hierarchy of SpatialObjects. We set the maximum level to 10
    // which is enough in this case since our hierarchy is only 2 deep.
    // Software Guide : EndLatex
    // Software Guide : BeginCodeSnippet
    itk::LevelOrderTreeIterator<TreeType> levelIt(tree,10);
    levelIt.GoToBegin();
    while(!levelIt.IsAtEnd())
      {
      std::cout << levelIt.Get()->GetId() << " ("<< levelIt.GetLevel()
        << ")" << std::endl;;
      ++levelIt;
      }
    // Software Guide : EndCodeSnippet
  
    // Software Guide : BeginLatex
    // Tree iterators can also be used to add spatial objects to the hierarchy. Here we show
    // how to use the \doxygen{PreOrderTreeIterator} to add a fourth object to the tree.
    // Software Guide : EndLatex
    // Software Guide : BeginCodeSnippet
    NodeType::Pointer object4 = NodeType::New();
    itk::PreOrderTreeIterator<TreeType> preIt( tree );
    preIt.Add(object4.GetPointer());
    // Software Guide : EndCodeSnippet
  
  
    return EXIT_SUCCESS;
  }
  
  