GraphAlgorithmFilter

VTKExamples/Cxx/Developers/GraphAlgorithmFilter

Description

This example demonstrates how to create a filter that takes a vtkGraph as input and produces a vtkGraph as output.

Code

GraphAlgorithmFilter.cxx

#include <vtkVersion.h>
#include <vtkSmartPointer.h>
#include <vtkGraph.h>
#include <vtkMutableUndirectedGraph.h>
#include <vtkMutableDirectedGraph.h>

#include "vtkTestGraphAlgorithmFilter.h"

void TestDirected();
void TestUndirected();

int main(int, char *[])
{
  TestDirected();
  TestUndirected();

  return EXIT_SUCCESS;
}

void TestDirected()
{

  vtkSmartPointer<vtkMutableDirectedGraph> g =
    vtkSmartPointer<vtkMutableDirectedGraph>::New();
  vtkIdType v1 = g->AddVertex();
  vtkIdType v2 = g->AddVertex();

  g->AddEdge(v1, v2);
  std::cout << "Input type: " << g->GetClassName() << std::endl;

  vtkSmartPointer<vtkTestGraphAlgorithmFilter> filter =
    vtkSmartPointer<vtkTestGraphAlgorithmFilter>::New();
#if VTK_MAJOR_VERSION <= 5
  filter->SetInput(g);
#else
  filter->SetInputData(g);
#endif
  filter->Update();

  std::cout << "Output type: " << filter->GetOutput()->GetClassName() << std::endl;
  std::cout << "Output has " << filter->GetOutput()->GetNumberOfVertices() << " vertices." << std::endl;
  std::cout << std::endl;
}

void TestUndirected()
{
  std::cout << "TestUndirected" << std::endl;
  vtkSmartPointer<vtkMutableUndirectedGraph> g =
    vtkSmartPointer<vtkMutableUndirectedGraph>::New();
  vtkIdType v1 = g->AddVertex();
  vtkIdType v2 = g->AddVertex();

  g->AddEdge(v1, v2);
  std::cout << "Input type: " << g->GetClassName() << std::endl;

  vtkSmartPointer<vtkTestGraphAlgorithmFilter> filter =
    vtkSmartPointer<vtkTestGraphAlgorithmFilter>::New();
#if VTK_MAJOR_VERSION <= 5
  filter->SetInput(g);
#else
  filter->SetInputData(g);
#endif
  filter->Update();

  std::cout << "Output type: " << filter->GetOutput()->GetClassName() << std::endl;
  std::cout << "Output has " << filter->GetOutput()->GetNumberOfVertices() << " vertices." << std::endl;
}

CMakeLists.txt

cmake_minimum_required(VERSION 2.8)

PROJECT(GraphAlgorithmFilter)

find_package(VTK REQUIRED)
include(${VTK_USE_FILE})

add_executable(GraphAlgorithmFilter MACOSX_BUNDLE GraphAlgorithmFilter.cxx)

target_link_libraries(GraphAlgorithmFilter ${VTK_LIBRARIES})

Download and Build GraphAlgorithmFilter

Danger

The generation of tar files has not been ported to the new VTKExamples. Some tarballs may be missing or out-of-date.

Click here to download GraphAlgorithmFilter and its CMakeLists.txt file. Once the tarball GraphAlgorithmFilter.tar has been downloaded and extracted,

cd GraphAlgorithmFilter/build 

If VTK is installed:

cmake ..

If VTK is not installed but compiled on your system, you will need to specify the path to your VTK build:

cmake -DVTK_DIR:PATH=/home/me/vtk_build ..

Build the project:

make

and run it:

./GraphAlgorithmFilter

WINDOWS USERS PLEASE NOTE: Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.