SelectionSource
VTKEx/Cxx/Filtering/SelectionSource
Question
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Code¶
SelectionSource.cxx
#include <vtkPointSource.h>
#include <vtkExtractSelection.h>
#include <vtkPolyData.h>
#include <vtkSelectionNode.h> // for POINT and INDICES enum values
#include <vtkSelectionSource.h>
#include <vtkSmartPointer.h>
int main(int, char *[])
{
// Note - this generates 50 points and a single poly-vertex cell.
vtkSmartPointer<vtkPointSource> pointSource =
vtkSmartPointer<vtkPointSource>::New();
pointSource->SetNumberOfPoints(50);
pointSource->Update();
std::cout << "There are " << pointSource->GetOutput()->GetNumberOfPoints() << " input points." << std::endl;
vtkSmartPointer<vtkSelectionSource> selectionSource =
vtkSmartPointer<vtkSelectionSource>::New();
selectionSource->SetFieldType(vtkSelectionNode::POINT);
selectionSource->SetContentType(vtkSelectionNode::INDICES);
// Without this line, all points are passed through because the 11 points
// we will select below are some of the points of the poly-vertex created
// by the PointSource, so the cell (by default) gets passed through since
// it contains some selected points, so therefore all of the points
// (the 50 belonging to the poly-vertex) also get passed through, which
// is not what we are trying to demonstrate.
selectionSource->SetContainingCells(false);
for (vtkIdType i = 10; i <= 20; i++)
{
selectionSource->AddID(0, i);
}
selectionSource->Update();
vtkSmartPointer<vtkExtractSelection> extractSelection =
vtkSmartPointer<vtkExtractSelection>::New();
extractSelection->SetInputConnection(0, pointSource->GetOutputPort());
extractSelection->SetInputConnection(1, selectionSource->GetOutputPort());
extractSelection->Update();
vtkDataSet* ds = dynamic_cast<vtkDataSet*> (extractSelection->GetOutput());
std::cout << "There are " << ds->GetNumberOfPoints() << " output points." << std::endl;
return EXIT_SUCCESS;
}
CMakeLists.txt¶
cmake_minimum_required(VERSION 3.3 FATAL_ERROR)
project(SelectionSource)
find_package(VTK COMPONENTS
vtkvtkCommonCore
vtkvtkCommonDataModel
vtkvtkFiltersExtraction
vtkvtkFiltersSources QUIET)
if (NOT VTK_FOUND)
message("Skipping SelectionSource: ${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(SelectionSource MACOSX_BUNDLE SelectionSource.cxx )
target_link_libraries(SelectionSource PRIVATE ${VTK_LIBRARIES})
else ()
# include all components
add_executable(SelectionSource MACOSX_BUNDLE SelectionSource.cxx )
target_link_libraries(SelectionSource PRIVATE ${VTK_LIBRARIES})
# vtk_module_autoinit is needed
vtk_module_autoinit(
TARGETS SelectionSource
MODULES ${VTK_LIBRARIES}
)
endif ()
Download and Build SelectionSource¶
Click here to download SelectionSource and its CMakeLists.txt file. Once the tarball SelectionSource.tar has been downloaded and extracted,
cd SelectionSource/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:
./SelectionSource
WINDOWS USERS
Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.