ConnectivityFilter

VTKExamples/Cxx/Filtering/ConnectivityFilter


Code

ConnectivityFilter.cxx

#include <vtkSmartPointer.h>
#include <vtkUnstructuredGrid.h>
#include <vtkSphereSource.h>
#include <vtkConnectivityFilter.h>
#include <vtkDataSetMapper.h>
#include <vtkActor.h>
#include <vtkProperty.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkAppendFilter.h>
#include <vtkDelaunay3D.h>

int main(int, char*[])
{
  vtkSmartPointer<vtkSphereSource> sphereSource1 =
    vtkSmartPointer<vtkSphereSource>::New();
  sphereSource1->Update();

  vtkSmartPointer<vtkDelaunay3D> delaunay1 =
    vtkSmartPointer<vtkDelaunay3D>::New();
  delaunay1->SetInputConnection(sphereSource1->GetOutputPort());
  delaunay1->Update();

  vtkSmartPointer<vtkSphereSource> sphereSource2 =
    vtkSmartPointer<vtkSphereSource>::New();
  sphereSource2->SetCenter(5,0,0);
  sphereSource2->Update();

  vtkSmartPointer<vtkDelaunay3D> delaunay2 =
    vtkSmartPointer<vtkDelaunay3D>::New();
  delaunay2->SetInputConnection(sphereSource2->GetOutputPort());
  delaunay2->Update();

  vtkSmartPointer<vtkAppendFilter> appendFilter =
    vtkSmartPointer<vtkAppendFilter>::New();
  appendFilter->AddInputConnection(delaunay1->GetOutputPort());
  appendFilter->AddInputConnection(delaunay2->GetOutputPort());
  appendFilter->Update();

  vtkSmartPointer<vtkConnectivityFilter> connectivityFilter =
    vtkSmartPointer<vtkConnectivityFilter>::New();
  connectivityFilter->SetInputConnection(appendFilter->GetOutputPort());
  connectivityFilter->SetExtractionModeToAllRegions();
  connectivityFilter->ColorRegionsOn();
  connectivityFilter->Update();

  // Visualize
  vtkSmartPointer<vtkDataSetMapper> mapper =
    vtkSmartPointer<vtkDataSetMapper>::New();
  mapper->SetInputConnection(connectivityFilter->GetOutputPort());
  mapper->Update();

  vtkSmartPointer<vtkActor> actor =
    vtkSmartPointer<vtkActor>::New();
  actor->SetMapper(mapper);

  vtkSmartPointer<vtkRenderer> renderer =
    vtkSmartPointer<vtkRenderer>::New();
  renderer->AddActor(actor);

  vtkSmartPointer<vtkRenderWindow> renwin =
    vtkSmartPointer<vtkRenderWindow>::New();
  renwin->AddRenderer(renderer);

  vtkSmartPointer<vtkRenderWindowInteractor> iren =
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  iren->SetRenderWindow(renwin);
  iren->Initialize();
  iren->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 2.8)

PROJECT(ConnectivityFilter)

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

add_executable(ConnectivityFilter MACOSX_BUNDLE ConnectivityFilter.cxx )

target_link_libraries(ConnectivityFilter ${VTK_LIBRARIES})

Download and Build ConnectivityFilter

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

cd ConnectivityFilter/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:

./ConnectivityFilter

WINDOWS USERS

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