GraphAlgorithmSource
VTKExamples/Cxx/Developers/GraphAlgorithmSource
Description¶
This example produces a vtkGraph as output.
Question
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Code¶
GraphAlgorithmSource.cxx
#include <vtkSmartPointer.h> #include <vtkGraph.h> #include <vtkMutableUndirectedGraph.h> #include "vtkTestGraphAlgorithmSource.h" int main (int, char *[]) { vtkSmartPointer<vtkTestGraphAlgorithmSource> source = vtkSmartPointer<vtkTestGraphAlgorithmSource>::New(); source->Update(); vtkGraph* outputGraph = source->GetOutput(); std::cout << "Output number of vertices: " << outputGraph->GetNumberOfVertices() << std::endl; return EXIT_SUCCESS; }
vtkTestGraphAlgorithmSource.h
#ifndef __vtkTestGraphAlgorithmSource_h #define __vtkTestGraphAlgorithmSource_h #include <vtkGraphAlgorithm.h> class vtkTestGraphAlgorithmSource : public vtkGraphAlgorithm { public: static vtkTestGraphAlgorithmSource *New(); vtkTypeMacro(vtkTestGraphAlgorithmSource,vtkGraphAlgorithm); void PrintSelf(ostream& os, vtkIndent indent) override; protected: vtkTestGraphAlgorithmSource(); ~vtkTestGraphAlgorithmSource(); int RequestData(vtkInformation *, vtkInformationVector **, vtkInformationVector *) override; int RequestDataObject(vtkInformation *, vtkInformationVector **, vtkInformationVector *) override; private: vtkTestGraphAlgorithmSource(const vtkTestGraphAlgorithmSource&); // Not implemented. void operator=(const vtkTestGraphAlgorithmSource&); // Not implemented. }; #endif
vtkTestGraphAlgorithmSource.cxx
#include "vtkTestGraphAlgorithmSource.h" #include <vtkObjectFactory.h> #include <vtkStreamingDemandDrivenPipeline.h> #include <vtkInformationVector.h> #include <vtkInformation.h> #include <vtkDataObject.h> #include <vtkSmartPointer.h> #include <vtkMutableUndirectedGraph.h> #include <vtkUndirectedGraph.h> #include <vtkGraph.h> vtkStandardNewMacro(vtkTestGraphAlgorithmSource); vtkTestGraphAlgorithmSource::vtkTestGraphAlgorithmSource() { this->SetNumberOfInputPorts(0); this->SetNumberOfOutputPorts(1); } vtkTestGraphAlgorithmSource::~vtkTestGraphAlgorithmSource() { } int vtkTestGraphAlgorithmSource::RequestData( vtkInformation *vtkNotUsed(request), vtkInformationVector **vtkNotUsed(inputVector), vtkInformationVector *outputVector) { vtkInformation *outInfo = outputVector->GetInformationObject(0); vtkGraph *output = dynamic_cast<vtkGraph*>( outInfo->Get(vtkDataObject::DATA_OBJECT())); vtkSmartPointer<vtkMutableUndirectedGraph> NewGraph = vtkSmartPointer<vtkMutableUndirectedGraph>::New(); //add 3 vertices NewGraph->AddVertex(); NewGraph->AddVertex(); NewGraph->AddVertex(); output->ShallowCopy(NewGraph); return 1; } int vtkTestGraphAlgorithmSource::RequestDataObject( vtkInformation*, vtkInformationVector**, vtkInformationVector* ) { vtkSmartPointer<vtkUndirectedGraph> output = vtkSmartPointer<vtkUndirectedGraph>::New(); this->GetExecutive()->SetOutputData(0, output); return 1; } //---------------------------------------------------------------------------- void vtkTestGraphAlgorithmSource::PrintSelf(ostream& os, vtkIndent indent) { this->Superclass::PrintSelf(os,indent); }
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR) project(GraphAlgorithmSource) find_package(VTK COMPONENTS vtkCommonCore vtkCommonDataModel QUIET) if (NOT VTK_FOUND) message("Skipping GraphAlgorithmSource: ${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(GraphAlgorithmSource MACOSX_BUNDLE GraphAlgorithmSource.cxx ) target_link_libraries(GraphAlgorithmSource PRIVATE ${VTK_LIBRARIES}) else () # include all components add_executable(GraphAlgorithmSource MACOSX_BUNDLE GraphAlgorithmSource.cxx ) target_link_libraries(GraphAlgorithmSource PRIVATE ${VTK_LIBRARIES}) # vtk_module_autoinit is needed vtk_module_autoinit( TARGETS GraphAlgorithmSource MODULES ${VTK_LIBRARIES} ) endif ()
Download and Build GraphAlgorithmSource¶
Click here to download GraphAlgorithmSource and its CMakeLists.txt file. Once the tarball GraphAlgorithmSource.tar has been downloaded and extracted,
cd GraphAlgorithmSource/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:
./GraphAlgorithmSource
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.