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ConstructGraph

vtk-examples/Cxx/Graphs/ConstructGraph


Description

This example shows how to construct a simple graph.

Other languages

See (Python)

Question

If you have a question about this example, please use the VTK Discourse Forum

Code

ConstructGraph.cxx

#include <vtkForceDirectedLayoutStrategy.h>
#include <vtkGraphLayoutView.h>
#include <vtkMutableUndirectedGraph.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>

int main(int, char*[])
{
  vtkNew<vtkNamedColors> colors;

  vtkNew<vtkMutableUndirectedGraph> g;

  vtkIdType v1 = g->AddVertex();
  vtkIdType v2 = g->AddVertex();

  g->AddEdge(v1, v2);

  std::cout << "Number of vertices: " << g->GetNumberOfVertices() << std::endl;
  std::cout << "Number of edges: " << g->GetNumberOfEdges() << std::endl;

  g->AddEdge(v1, v2);

  std::cout << "Number of vertices: " << g->GetNumberOfVertices() << std::endl;
  std::cout << "Number of edges: " << g->GetNumberOfEdges() << std::endl;

  vtkNew<vtkForceDirectedLayoutStrategy> forceDirected;

  vtkNew<vtkGraphLayoutView> graphLayoutView;
  graphLayoutView->AddRepresentationFromInput(g);
  // If we create a layout object directly, just set the pointer through this
  // method.
  // graphLayoutView->SetLayoutStrategy(forceDirected);
  graphLayoutView->SetLayoutStrategyToForceDirected();
  graphLayoutView->ResetCamera();
  graphLayoutView->GetRenderer()->SetBackground(
      colors->GetColor3d("Navy").GetData());
  graphLayoutView->GetRenderer()->SetBackground2(
      colors->GetColor3d("MidnightBlue").GetData());
  graphLayoutView->GetRenderWindow()->SetWindowName("ConstructGraph");
  graphLayoutView->Render();
  graphLayoutView->GetInteractor()->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(ConstructGraph)

find_package(VTK COMPONENTS 
  vtkCommonColor
  vtkCommonCore
  vtkCommonDataModel
  vtkInfovisLayout
  vtkInteractionStyle
  vtkRenderingContextOpenGL2
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingGL2PSOpenGL2
  vtkRenderingOpenGL2
  vtkViewsInfovis
  QUIET
)

if (NOT VTK_FOUND)
  message("Skipping ConstructGraph: ${VTK_NOT_FOUND_MESSAGE}")
  return ()
endif()
message (STATUS "VTK_VERSION: ${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
  # old system
  include(${VTK_USE_FILE})
  add_executable(ConstructGraph MACOSX_BUNDLE ConstructGraph.cxx )
  target_link_libraries(ConstructGraph PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(ConstructGraph MACOSX_BUNDLE ConstructGraph.cxx )
  target_link_libraries(ConstructGraph PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS ConstructGraph
    MODULES ${VTK_LIBRARIES}
    )
endif ()

Download and Build ConstructGraph

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

cd ConstructGraph/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:

./ConstructGraph

WINDOWS USERS

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