GraphToPolyData
VTKExamples/Cxx/Graphs/GraphToPolyData
Description¶
This example creates a simple graph and then converts it to a polydata for visualization using Paraview.
Code¶
GraphToPolyData.cxx
#include <vtkSmartPointer.h> #include <vtkPoints.h> #include <vtkMutableUndirectedGraph.h> #include <vtkGraphToPolyData.h> #include <vtkPolyDataMapper.h> #include <vtkActor.h> #include <vtkRenderWindow.h> #include <vtkRenderer.h> #include <vtkRenderWindowInteractor.h> int main(int, char *[]) { // Create a graph vtkSmartPointer<vtkMutableUndirectedGraph> g = vtkSmartPointer<vtkMutableUndirectedGraph>::New(); // Add 4 vertices to the graph vtkIdType v1 = g->AddVertex(); vtkIdType v2 = g->AddVertex(); vtkIdType v3 = g->AddVertex(); vtkIdType v4 = g->AddVertex(); // Add 3 edges to the graph g->AddEdge ( v1, v2 ); g->AddEdge ( v1, v3 ); g->AddEdge ( v1, v4 ); // Create 4 points - one for each vertex vtkSmartPointer<vtkPoints> points = vtkSmartPointer<vtkPoints>::New(); points->InsertNextPoint(0.0, 0.0, 0.0); points->InsertNextPoint(1.0, 0.0, 0.0); points->InsertNextPoint(0.0, 1.0, 0.0); points->InsertNextPoint(0.0, 0.0, 1.0); // Add the coordinates of the points to the graph g->SetPoints(points); // Convert the graph to a polydata vtkSmartPointer<vtkGraphToPolyData> graphToPolyData = vtkSmartPointer<vtkGraphToPolyData>::New(); graphToPolyData->SetInput(g); graphToPolyData->Update(); // Create a mapper and actor vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New(); mapper->SetInputConnection(graphToPolyData->GetOutputPort()); vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New(); actor->SetMapper(mapper); // 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 actor to the scene renderer->AddActor(actor); renderer->SetBackground(.3, .6, .3); // Background color green // Render and interact renderWindow->Render(); renderWindowInteractor->Start(); return EXIT_SUCCESS; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 2.8) PROJECT(GraphToPolyData) find_package(VTK REQUIRED) include(${VTK_USE_FILE}) add_executable(GraphToPolyData MACOSX_BUNDLE GraphToPolyData.cxx) target_link_libraries(GraphToPolyData ${VTK_LIBRARIES})
Download and Build GraphToPolyData¶
Danger
The generation of tar files has not been ported to the new VTKExamples. Some tarballs may be missing or out-of-date.
Click here to download GraphToPolyData and its CMakeLists.txt file. Once the tarball GraphToPolyData.tar has been downloaded and extracted,
cd GraphToPolyData/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:
./GraphToPolyData
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.