PolyDataConnectivityFilter SpecifiedRegion
VTKExamples/Cxx/PolyData/PolyDataConnectivityFilter_SpecifiedRegion
Description
This example creates two spheres and combines them together into one polydata. The vtkPolyDataConnectivityFilter is used to find the two spheres as they are separate regions (disconnected). If region 0 is selected, the small sphere is extracted. If region 1 is selected, the large sphere is extracted.
Code
PolyDataConnectivityFilter_SpecifiedRegion.cxx
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkPolyDataConnectivityFilter.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkProperty.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkAppendPolyData.h>
int main(int, char *[])
{
vtkSmartPointer<vtkSphereSource> sphereSource1 =
vtkSmartPointer<vtkSphereSource>::New();
sphereSource1->Update();
vtkSmartPointer<vtkSphereSource> sphereSource2 =
vtkSmartPointer<vtkSphereSource>::New();
sphereSource2->SetRadius(10);
sphereSource2->SetCenter(25,0,0);
sphereSource2->Update();
vtkSmartPointer<vtkAppendPolyData> appendFilter =
vtkSmartPointer<vtkAppendPolyData>::New();
appendFilter->AddInputConnection(sphereSource1->GetOutputPort());
appendFilter->AddInputConnection(sphereSource2->GetOutputPort());
appendFilter->Update();
vtkSmartPointer<vtkPolyDataConnectivityFilter> connectivityFilter =
vtkSmartPointer<vtkPolyDataConnectivityFilter>::New();
connectivityFilter->SetInputConnection(appendFilter->GetOutputPort());
connectivityFilter->SetExtractionModeToSpecifiedRegions();
connectivityFilter->AddSpecifiedRegion(1); //select the region to extract here
connectivityFilter->Update();
// Create a mapper and actor for original data
vtkSmartPointer<vtkPolyDataMapper> originalMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
originalMapper->SetInputConnection(appendFilter->GetOutputPort());
originalMapper->Update();
vtkSmartPointer<vtkActor> originalActor =
vtkSmartPointer<vtkActor>::New();
originalActor->SetMapper(originalMapper);
// create a mapper and actor for extracted data
vtkSmartPointer<vtkPolyDataMapper> extractedMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
extractedMapper->SetInputConnection(connectivityFilter->GetOutputPort());
extractedMapper->Update();
vtkSmartPointer<vtkActor> extractedActor =
vtkSmartPointer<vtkActor>::New();
extractedActor->GetProperty()->SetColor(1,0,0);
extractedActor->SetMapper(extractedMapper);
// create a renderer
vtkSmartPointer<vtkRenderer> renderer =
vtkSmartPointer<vtkRenderer>::New();
renderer->AddActor(originalActor);
renderer->AddActor(extractedActor);
// create a render window
vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->AddRenderer(renderer);
// create an interactor
vtkSmartPointer<vtkRenderWindowInteractor> interactor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
interactor->SetRenderWindow(renderWindow);
interactor->Initialize();
interactor->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt
cmake_minimum_required(VERSION 2.8)
PROJECT(PolyDataConnectivityFilter_SpecifiedRegion)
find_package(VTK REQUIRED)
include(${VTK_USE_FILE})
add_executable(PolyDataConnectivityFilter_SpecifiedRegion MACOSX_BUNDLE PolyDataConnectivityFilter_SpecifiedRegion.cxx)
target_link_libraries(PolyDataConnectivityFilter_SpecifiedRegion ${VTK_LIBRARIES})
Download and Build PolyDataConnectivityFilter_SpecifiedRegion
Click here to download PolyDataConnectivityFilter_SpecifiedRegion and its CMakeLists.txt file. Once the tarball PolyDataConnectivityFilter_SpecifiedRegion.tar has been downloaded and extracted,
cd PolyDataConnectivityFilter_SpecifiedRegion/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:
./PolyDataConnectivityFilter_SpecifiedRegion
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.