VertexConnectivity
VTKExamples/Cxx/PolyData/VertexConnectivity
Description¶
The input must be only edges (i.e. vtkExtractEdges must be run).
Question
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Code¶
VertexConnectivity.cxx
#include <vtkSmartPointer.h> #include <vtkIdList.h> #include <vtkPolyData.h> #include <vtkCellData.h> #include <vtkDoubleArray.h> #include <vtkDataSet.h> #include <vtkSphereSource.h> #include <vtkTriangleFilter.h> #include <vtkExtractEdges.h> #include <vtkDataSetMapper.h> #include <vtkActor.h> #include <vtkRenderWindow.h> #include <vtkRenderer.h> #include <vtkRenderWindowInteractor.h> #include <vtkIdTypeArray.h> #include <vtkSelectionNode.h> #include <vtkSelection.h> #include <vtkExtractSelection.h> #include <vtkProperty.h> #include <vtkVertexGlyphFilter.h> vtkSmartPointer<vtkIdList> GetConnectedVertices(vtkSmartPointer<vtkPolyData> mesh, int id); int main(int, char *[]) { vtkSmartPointer<vtkSphereSource> sphereSource = vtkSmartPointer<vtkSphereSource>::New(); sphereSource->Update(); vtkSmartPointer<vtkTriangleFilter> triangleFilter = vtkSmartPointer<vtkTriangleFilter>::New(); triangleFilter->SetInputConnection(sphereSource->GetOutputPort()); triangleFilter->Update(); vtkSmartPointer<vtkExtractEdges> extractEdges = vtkSmartPointer<vtkExtractEdges>::New(); extractEdges->SetInputConnection(triangleFilter->GetOutputPort()); extractEdges->Update(); vtkSmartPointer<vtkPolyData> mesh = extractEdges->GetOutput(); vtkSmartPointer<vtkIdList> connectedVertices = GetConnectedVertices(mesh, 0); vtkSmartPointer<vtkIdTypeArray> ids = vtkSmartPointer<vtkIdTypeArray>::New(); ids->SetNumberOfComponents(1); std::cout << "Connected vertices: "; for(vtkIdType i = 0; i < connectedVertices->GetNumberOfIds(); i++) { std::cout << connectedVertices->GetId(i) << " "; ids->InsertNextValue(connectedVertices->GetId(i)); } std::cout << std::endl; vtkSmartPointer<vtkDataSetMapper> connectedVertexMapper = vtkSmartPointer<vtkDataSetMapper>::New(); { 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, extractEdges->GetOutputPort()); extractSelection->SetInputData(1, selection); extractSelection->Update(); vtkSmartPointer<vtkVertexGlyphFilter> glyphFilter = vtkSmartPointer<vtkVertexGlyphFilter>::New(); glyphFilter->SetInputConnection(extractSelection->GetOutputPort()); glyphFilter->Update(); connectedVertexMapper->SetInputConnection(glyphFilter->GetOutputPort()); } vtkSmartPointer<vtkActor> connectedVertexActor = vtkSmartPointer<vtkActor>::New(); connectedVertexActor->SetMapper(connectedVertexMapper); connectedVertexActor->GetProperty()->SetColor(1,0,0); connectedVertexActor->GetProperty()->SetPointSize(5); vtkSmartPointer<vtkDataSetMapper> queryVertexMapper = vtkSmartPointer<vtkDataSetMapper>::New(); { vtkSmartPointer<vtkIdTypeArray> ids2 = vtkSmartPointer<vtkIdTypeArray>::New(); ids2->SetNumberOfComponents(1); ids2->InsertNextValue(0); vtkSmartPointer<vtkSelectionNode> selectionNode = vtkSmartPointer<vtkSelectionNode>::New(); selectionNode->SetFieldType(vtkSelectionNode::POINT); selectionNode->SetContentType(vtkSelectionNode::INDICES); selectionNode->SetSelectionList(ids2); vtkSmartPointer<vtkSelection> selection = vtkSmartPointer<vtkSelection>::New(); selection->AddNode(selectionNode); vtkSmartPointer<vtkExtractSelection> extractSelection = vtkSmartPointer<vtkExtractSelection>::New(); extractSelection->SetInputConnection(0, extractEdges->GetOutputPort()); extractSelection->SetInputData(1, selection); extractSelection->Update(); vtkSmartPointer<vtkVertexGlyphFilter> glyphFilter = vtkSmartPointer<vtkVertexGlyphFilter>::New(); glyphFilter->SetInputConnection(extractSelection->GetOutputPort()); glyphFilter->Update(); queryVertexMapper->SetInputConnection(glyphFilter->GetOutputPort()); } vtkSmartPointer<vtkActor> queryVertexActor = vtkSmartPointer<vtkActor>::New(); queryVertexActor->SetMapper(queryVertexMapper); queryVertexActor->GetProperty()->SetColor(0,1,0); queryVertexActor->GetProperty()->SetPointSize(5); vtkSmartPointer<vtkDataSetMapper> sphereMapper = vtkSmartPointer<vtkDataSetMapper>::New(); sphereMapper->SetInputConnection(extractEdges->GetOutputPort()); vtkSmartPointer<vtkActor> sphereActor = vtkSmartPointer<vtkActor>::New(); sphereActor->SetMapper(sphereMapper); //Create a renderer, render window, and interactor vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New(); vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New(); renderWindow->AddRenderer(renderer); vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = vtkSmartPointer<vtkRenderWindowInteractor>::New(); renderWindowInteractor->SetRenderWindow(renderWindow); //Add the actors to the scene renderer->AddActor(sphereActor); renderer->AddActor(queryVertexActor); renderer->AddActor(connectedVertexActor); renderer->SetBackground(.3, .2, .1); // Background color dark red //Render and interact renderWindow->Render(); renderWindowInteractor->Start(); return EXIT_SUCCESS; } vtkSmartPointer<vtkIdList> GetConnectedVertices(vtkSmartPointer<vtkPolyData> mesh, int id) { vtkSmartPointer<vtkIdList> connectedVertices = vtkSmartPointer<vtkIdList>::New(); //get all cells that vertex 'id' is a part of vtkSmartPointer<vtkIdList> cellIdList = vtkSmartPointer<vtkIdList>::New(); mesh->GetPointCells(id, cellIdList); /* cout << "Vertex 0 is used in cells "; for(vtkIdType i = 0; i < cellIdList->GetNumberOfIds(); i++) { cout << cellIdList->GetId(i) << ", "; } cout << endl; */ for(vtkIdType i = 0; i < cellIdList->GetNumberOfIds(); i++) { //cout << "id " << i << " : " << cellIdList->GetId(i) << endl; vtkSmartPointer<vtkIdList> pointIdList = vtkSmartPointer<vtkIdList>::New(); mesh->GetCellPoints(cellIdList->GetId(i), pointIdList); //cout << "End points are " << pointIdList->GetId(0) << " and " << pointIdList->GetId(1) << endl; if(pointIdList->GetId(0) != id) { //cout << "Connected to " << pointIdList->GetId(0) << endl; connectedVertices->InsertNextId(pointIdList->GetId(0)); } else { //cout << "Connected to " << pointIdList->GetId(1) << endl; connectedVertices->InsertNextId(pointIdList->GetId(1)); } } return connectedVertices; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR) project(VertexConnectivity) find_package(VTK COMPONENTS vtkCommonCore vtkCommonDataModel vtkFiltersCore vtkFiltersExtraction vtkFiltersGeneral vtkFiltersSources vtkInteractionStyle vtkRenderingCore vtkRenderingFreeType vtkRenderingOpenGL2 QUIET) if (NOT VTK_FOUND) message("Skipping VertexConnectivity: ${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(VertexConnectivity MACOSX_BUNDLE VertexConnectivity.cxx ) target_link_libraries(VertexConnectivity PRIVATE ${VTK_LIBRARIES}) else () # include all components add_executable(VertexConnectivity MACOSX_BUNDLE VertexConnectivity.cxx ) target_link_libraries(VertexConnectivity PRIVATE ${VTK_LIBRARIES}) # vtk_module_autoinit is needed vtk_module_autoinit( TARGETS VertexConnectivity MODULES ${VTK_LIBRARIES} ) endif ()
Download and Build VertexConnectivity¶
Click here to download VertexConnectivity and its CMakeLists.txt file. Once the tarball VertexConnectivity.tar has been downloaded and extracted,
cd VertexConnectivity/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:
./VertexConnectivity
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.