BreadthFirstDistance
VTKExamples/Cxx/Graphs/BreadthFirstDistance
Description¶
This example shows how to get the distance from a vertex to the root vertex.
Code¶
BreadthFirstDistance.cxx
#include <vtkSmartPointer.h> #include <vtkBoostBreadthFirstSearch.h> #include <vtkDataSetAttributes.h> #include <vtkDoubleArray.h> #include <vtkIntArray.h> #include <vtkMutableUndirectedGraph.h> #include <vtkTree.h> int main(int, char *[]) { vtkSmartPointer<vtkMutableUndirectedGraph> g = vtkSmartPointer<vtkMutableUndirectedGraph>::New(); // Create 3 vertices vtkIdType v1 = g->AddVertex(); vtkIdType v2 = g->AddVertex(); vtkIdType v3 = g->AddVertex(); vtkIdType v4 = g->AddVertex(); // Create a graph g->AddEdge(v1, v2); g->AddEdge(v1, v3); g->AddEdge(v2, v4); vtkSmartPointer<vtkBoostBreadthFirstSearch> BFS = vtkSmartPointer<vtkBoostBreadthFirstSearch>::New(); BFS->SetOriginVertex(v1); BFS->SetInput(g); BFS->Update(); vtkIntArray* level = vtkIntArray::SafeDownCast( BFS->GetOutput()->GetVertexData()->GetArray("BFS")); for(vtkIdType i = 0; i < level->GetNumberOfTuples(); i++) { std::cout << "id " << i << " : " << level->GetValue(i) << std::endl; } return EXIT_SUCCESS; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 2.8) PROJECT(BreadthFirstDistance) find_package(VTK REQUIRED) include(${VTK_USE_FILE}) add_executable(BreadthFirstDistance MACOSX_BUNDLE BreadthFirstDistance.cxx) target_link_libraries(BreadthFirstDistance ${VTK_LIBRARIES})
Download and Build BreadthFirstDistance¶
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 Some tarballs may be missing or out-of-date.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 BreadthFirstDistance and its CMakeLists.txt file. Once the tarball BreadthFirstDistance.tar has been downloaded and extracted,
cd BreadthFirstDistance/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:
./BreadthFirstDistance
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.