SplitPolyData
VTKExamples/Cxx/Meshes/SplitPolyData
Description¶
The vtkOBBDicer filter breaks up an input mesh into a number of pieces. The resulting mesh contains scalar point data that can be used to extract the individual pieces with a filter like vtkThresholdFilter. This example stores each piece into a .vtp file.
Code¶
SplitPolyData.cxx
#include <vtkVersion.h> #include <vtkSmartPointer.h> #include <vtkOBBDicer.h> #include <vtkSphereSource.h> #include <vtkXMLPolyDataReader.h> #include <vtkXMLPolyDataWriter.h> #include <vtkThreshold.h> #include <vtkGeometryFilter.h> #include <vtksys/SystemTools.hxx> #include <sstream> int main(int argc, char *argv[]) { std::string filename; std::string extension; vtkSmartPointer<vtkPolyData> inputPolyData; if(argc > 1) { filename = vtksys::SystemTools::GetFilenameWithoutExtension(std::string(argv[1])); extension = vtksys::SystemTools::GetFilenameExtension(std::string(argv[1])); vtkSmartPointer<vtkXMLPolyDataReader> reader = vtkSmartPointer<vtkXMLPolyDataReader>::New(); reader->SetFileName(argv[1]); reader->Update(); inputPolyData = reader->GetOutput(); } else { filename = "sphere"; extension = ".vtp"; vtkSmartPointer<vtkSphereSource> sphereSource = vtkSmartPointer<vtkSphereSource>::New(); sphereSource->SetThetaResolution(30); sphereSource->SetPhiResolution(15); sphereSource->Update(); inputPolyData = sphereSource->GetOutput(); } // Create pipeline vtkSmartPointer<vtkOBBDicer> dicer = vtkSmartPointer<vtkOBBDicer>::New(); #if VTK_MAJOR_VERSION <= 5 dicer->SetInput(inputPolyData); #else dicer->SetInputData(inputPolyData); #endif dicer->SetNumberOfPieces(4); dicer->SetDiceModeToSpecifiedNumberOfPieces(); dicer->Update(); vtkSmartPointer<vtkThreshold> selector = vtkSmartPointer<vtkThreshold>::New(); selector->SetInputArrayToProcess(0, 0, 0, 0, "vtkOBBDicer_GroupIds"); selector->SetInputConnection(dicer->GetOutputPort()); selector->AllScalarsOff(); vtkSmartPointer<vtkGeometryFilter> geometry = vtkSmartPointer<vtkGeometryFilter>::New(); geometry->SetInputConnection(selector->GetOutputPort()); vtkSmartPointer<vtkXMLPolyDataWriter> writer = vtkSmartPointer<vtkXMLPolyDataWriter>::New(); writer->SetInputConnection(geometry->GetOutputPort()); for (int i = 0; i < dicer->GetNumberOfActualPieces(); ++i) { std::stringstream pieceName; pieceName << filename << "_" << i + 1 << extension; selector->ThresholdBetween(i, i); writer->SetFileName(pieceName.str().c_str()); writer->Write(); } return EXIT_SUCCESS; }
CMakeLists.txt¶
cmake_minimum_required(VERSION 2.8) PROJECT(SplitPolyData) find_package(VTK REQUIRED) include(${VTK_USE_FILE}) add_executable(SplitPolyData MACOSX_BUNDLE SplitPolyData.cxx) target_link_libraries(SplitPolyData ${VTK_LIBRARIES})
Download and Build SplitPolyData¶
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 SplitPolyData and its CMakeLists.txt file. Once the tarball SplitPolyData.tar has been downloaded and extracted,
cd SplitPolyData/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:
./SplitPolyData
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.