ExtractSelectionOriginalId
VTKExamples/Cxx/PolyData/ExtractSelectionOriginalId
Question
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Code¶
ExtractSelectionOriginalId.cxx
#include <vtkSmartPointer.h> #include <vtkPointData.h> #include <vtkIdTypeArray.h> #include <vtkInformation.h> #include <vtkPointSource.h> #include <vtkExtractSelection.h> #include <vtkSelection.h> #include <vtkSelectionNode.h> #include <vtkPolyData.h> #include <vtkUnstructuredGrid.h> #include <vtkIdTypeArray.h> #include <vtkDataSetMapper.h> #include <vtkProperty.h> #include <vtkRenderWindow.h> #include <vtkRenderWindowInteractor.h> #include <vtkRenderer.h> #include <vtkSphereSource.h> #include <vtkVertexGlyphFilter.h> int main(int, char *[]) { vtkSmartPointer<vtkPointSource> pointSource = vtkSmartPointer<vtkPointSource>::New(); pointSource->SetNumberOfPoints(50); pointSource->Update(); std::cout << "There are " << pointSource->GetOutput()->GetNumberOfPoints() << " input points." << std::endl; vtkSmartPointer<vtkIdTypeArray> ids = vtkSmartPointer<vtkIdTypeArray>::New(); ids->SetNumberOfComponents(1); //set values for(unsigned int i = 10; i < 20; i++) { ids->InsertNextValue(i); } vtkSmartPointer<vtkSelectionNode> selectionNode = vtkSmartPointer<vtkSelectionNode>::New(); selectionNode->SetFieldType(vtkSelectionNode::POINT); selectionNode->SetContentType(vtkSelectionNode::INDICES); selectionNode->SetSelectionList(ids); vtkSmartPointer<vtkSelection> selection = vtkSmartPointer<vtkSelection>::New(); selection->AddNode(selectionNode); vtkSmartPointer<vtkExtractSelection> extractSelection = vtkSmartPointer<vtkExtractSelection>::New(); extractSelection->SetInputConnection(0, pointSource->GetOutputPort()); extractSelection->SetInputData(1, selection); extractSelection->Update(); //in selection vtkSmartPointer<vtkUnstructuredGrid> selected = vtkSmartPointer<vtkUnstructuredGrid>::New(); selected->ShallowCopy(extractSelection->GetOutput()); std::cout << "There are " << selected->GetNumberOfPoints() << " points in the selection." << std::endl; selected->Print(std::cout); vtkIdTypeArray* originalIds = dynamic_cast<vtkIdTypeArray*>(selected->GetPointData()->GetArray("vtkOriginalPointIds")); for(vtkIdType i = 0; i < originalIds->GetNumberOfTuples(); i++) { std::cout << "Point " << i << " was originally point " << originalIds->GetValue(i) << std::endl; } for(vtkIdType i = 0; i < originalIds->GetNumberOfTuples(); i++) { vtkIdType query = originalIds->GetValue(i); for(vtkIdType j = 0; j < originalIds->GetNumberOfTuples(); j++) { if(originalIds->GetValue(j) == query) { std::cout << "Original point " << query << " is now " << j << std::endl; } } } vtkSmartPointer<vtkDataSetMapper> inputMapper = vtkSmartPointer<vtkDataSetMapper>::New(); inputMapper->SetInputConnection(pointSource->GetOutputPort()); vtkSmartPointer<vtkActor> inputActor = vtkSmartPointer<vtkActor>::New(); inputActor->SetMapper(inputMapper); vtkSmartPointer<vtkDataSetMapper> selectedMapper = vtkSmartPointer<vtkDataSetMapper>::New(); selectedMapper->SetInputData(selected); vtkSmartPointer<vtkActor> selectedActor = vtkSmartPointer<vtkActor>::New(); selectedActor->SetMapper(selectedMapper); // There will be one render window vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New(); renderWindow->SetSize(900, 300); // And one interactor vtkSmartPointer<vtkRenderWindowInteractor> interactor = vtkSmartPointer<vtkRenderWindowInteractor>::New(); interactor->SetRenderWindow(renderWindow); // Define viewport ranges // (xmin, ymin, xmax, ymax) double leftViewport[4] = {0.0, 0.0, 0.5, 1.0}; double rightViewport[4] = {0.5, 0.0, 1.0, 1.0}; // Setup the renderers vtkSmartPointer<vtkRenderer> leftRenderer = vtkSmartPointer<vtkRenderer>::New(); renderWindow->AddRenderer(leftRenderer); leftRenderer->SetViewport(leftViewport); leftRenderer->SetBackground(.6, .5, .4); vtkSmartPointer<vtkRenderer> rightRenderer = vtkSmartPointer<vtkRenderer>::New(); renderWindow->AddRenderer(rightRenderer); rightRenderer->SetViewport(rightViewport); rightRenderer->SetBackground(.4, .5, .6); leftRenderer->AddActor(inputActor); rightRenderer->AddActor(selectedActor); leftRenderer->ResetCamera(); rightRenderer->ResetCamera(); renderWindow->Render(); interactor->Start(); return EXIT_SUCCESS; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR) project(ExtractSelectionOriginalId) find_package(VTK COMPONENTS vtkCommonCore vtkCommonDataModel vtkFiltersExtraction vtkFiltersGeneral vtkFiltersSources vtkInteractionStyle vtkRenderingContextOpenGL2 vtkRenderingCore vtkRenderingFreeType vtkRenderingGL2PSOpenGL2 vtkRenderingOpenGL2 QUIET) if (NOT VTK_FOUND) message("Skipping ExtractSelectionOriginalId: ${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(ExtractSelectionOriginalId MACOSX_BUNDLE ExtractSelectionOriginalId.cxx ) target_link_libraries(ExtractSelectionOriginalId PRIVATE ${VTK_LIBRARIES}) else () # include all components add_executable(ExtractSelectionOriginalId MACOSX_BUNDLE ExtractSelectionOriginalId.cxx ) target_link_libraries(ExtractSelectionOriginalId PRIVATE ${VTK_LIBRARIES}) # vtk_module_autoinit is needed vtk_module_autoinit( TARGETS ExtractSelectionOriginalId MODULES ${VTK_LIBRARIES} ) endif ()
Download and Build ExtractSelectionOriginalId¶
Click here to download ExtractSelectionOriginalId and its CMakeLists.txt file. Once the tarball ExtractSelectionOriginalId.tar has been downloaded and extracted,
cd ExtractSelectionOriginalId/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:
./ExtractSelectionOriginalId
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.