GetCellCenter
VTKExamples/Cxx/ImageData/GetCellCenter
Description¶
Unfortunately this function is not built in directly, but rather quite convoluted to call. This is an easy to use wrapper.
Code¶
GetCellCenter.cxx
#include <vtkSmartPointer.h> #include <vtkCell.h> #include <vtkImageData.h> static void GetCellCenter(vtkImageData* imageData, const unsigned int cellId, double center[3]); int main(int, char *[]) { // Create an image data vtkSmartPointer<vtkImageData> imageData = vtkSmartPointer<vtkImageData>::New(); // Specify the size of the image data imageData->SetDimensions(3,3,2); // This will cause 18 points and 4 cells imageData->SetSpacing(1.0, 1.0, 1.0); imageData->SetOrigin(0.0, 0.0, 0.0); std::cout << "Number of points: " << imageData->GetNumberOfPoints() << std::endl; std::cout << "Number of cells: " << imageData->GetNumberOfCells() << std::endl; double center[3] = {0,0,0}; for(vtkIdType cellId = 0; cellId < imageData->GetNumberOfCells(); ++cellId) { GetCellCenter(imageData, cellId, center); std::cout << "Cell " << cellId << " center: " << center[0] << " " << center[1] << " " << center[2] << std::endl; } return EXIT_SUCCESS; } void GetCellCenter(vtkImageData* imageData, const unsigned int cellId, double center[3]) { double pcoords[3] = {0,0,0}; double *weights = new double [imageData->GetMaxCellSize()]; vtkCell* cell = imageData->GetCell(cellId); int subId = cell->GetParametricCenter(pcoords); cell->EvaluateLocation(subId, pcoords, center, weights); }
CMakeLists.txt¶
cmake_minimum_required(VERSION 2.8) PROJECT(GetCellCenter) find_package(VTK REQUIRED) include(${VTK_USE_FILE}) add_executable(GetCellCenter MACOSX_BUNDLE GetCellCenter.cxx) target_link_libraries(GetCellCenter ${VTK_LIBRARIES})
Download and Build GetCellCenter¶
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 Some tarballs may be missing or out-of-date.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 GetCellCenter and its CMakeLists.txt file. Once the tarball GetCellCenter.tar has been downloaded and extracted,
cd GetCellCenter/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:
./GetCellCenter
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.