ResamplePolyLine

VTKExamples/Cxx/PolyData/ResamplePolyLine

Description¶

This example resamples a polyline with a vtkCardinalSpline. The resampled line will have 10 times the number of points contained in the original polyline. If no XML file is provided, a random polyline is generated.

Question

Code¶

ResamplePolyLine.cxx

#include <vtkActor.h>
#include <vtkCardinalSpline.h>
#include <vtkCellArray.h>
#include <vtkGlyph3D.h>
#include <vtkMath.h>
#include <vtkPoints.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderer.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkSplineFilter.h>

int main (int argc, char *argv[])
{
vtkSmartPointer<vtkPolyData> polyData =
vtkSmartPointer<vtkPolyData>::New();
if (argc > 1)
{
}
else
{
vtkMath::RandomSeed(8775070);
unsigned int numberOfPoints = 10;
vtkSmartPointer<vtkPoints> points =
vtkSmartPointer<vtkPoints>::New();
for (unsigned int i = 0; i < numberOfPoints; ++i)
{
double x = vtkMath::Random(-1, 1);
double y = vtkMath::Random(-1, 1);
double z = vtkMath::Random(-1, 1);
points->InsertNextPoint(x, y, z);
}
vtkSmartPointer<vtkCellArray> lines =
vtkSmartPointer<vtkCellArray>::New();
lines->InsertNextCell(numberOfPoints);
for (unsigned int i = 0; i < numberOfPoints; ++i)
{
lines->InsertCellPoint(i);
}
polyData->SetPoints(points);
polyData->SetLines(lines);
}

vtkSmartPointer<vtkCardinalSpline> spline =
vtkSmartPointer<vtkCardinalSpline>::New();
spline->SetLeftConstraint(2);
spline->SetLeftValue(0.0);
spline->SetRightConstraint(2);
spline->SetRightValue(0.0);

vtkSmartPointer<vtkSplineFilter> splineFilter =
vtkSmartPointer<vtkSplineFilter>::New();
splineFilter->SetInputData(polyData);
splineFilter->SetNumberOfSubdivisions(polyData->GetNumberOfPoints() * 10);
splineFilter->SetSpline(spline);

vtkSmartPointer<vtkPolyDataMapper> splineMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
splineMapper->SetInputConnection(splineFilter->GetOutputPort());

vtkSmartPointer<vtkActor> splineActor =
vtkSmartPointer<vtkActor>::New();
splineActor->SetMapper(splineMapper);

vtkSmartPointer<vtkSphereSource> originalNodes =
vtkSmartPointer<vtkSphereSource>::New();
originalNodes->SetPhiResolution(10);
originalNodes->SetThetaResolution(10);

vtkSmartPointer<vtkGlyph3D> glyphOriginal =
vtkSmartPointer<vtkGlyph3D>::New();
glyphOriginal->SetInputData(polyData);
glyphOriginal->SetSourceConnection(originalNodes->GetOutputPort());

vtkSmartPointer<vtkSphereSource> newNodes =
vtkSmartPointer<vtkSphereSource>::New();
newNodes->SetPhiResolution(10);
newNodes->SetThetaResolution(10);

vtkSmartPointer<vtkGlyph3D> glyphNew =
vtkSmartPointer<vtkGlyph3D>::New();
glyphNew->SetInputConnection(splineFilter->GetOutputPort());
glyphNew->SetSourceConnection(newNodes->GetOutputPort());

vtkSmartPointer<vtkPolyDataMapper> originalMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
originalMapper->SetInputConnection(glyphOriginal->GetOutputPort());

vtkSmartPointer<vtkActor> originalActor =
vtkSmartPointer<vtkActor>::New();
originalActor->SetMapper(originalMapper);
originalActor->GetProperty()->SetColor(0.8900, 0.8100, 0.3400);
originalActor->GetProperty()->SetOpacity(.6);

vtkSmartPointer<vtkPolyDataMapper> newMapper =
vtkSmartPointer<vtkPolyDataMapper>::New();
newMapper->SetInputConnection(glyphNew->GetOutputPort());

vtkSmartPointer<vtkActor> newActor =
vtkSmartPointer<vtkActor>::New();
newActor->SetMapper(newMapper);
newActor->GetProperty()->SetColor(1.0000, 0.3882, 0.2784);

// A renderer and render window
vtkSmartPointer<vtkRenderer> renderer =
vtkSmartPointer<vtkRenderer>::New();
renderer->SetBackground(.1, .2, .4);

vtkSmartPointer<vtkRenderWindow> renderWindow =
vtkSmartPointer<vtkRenderWindow>::New();

// An interactor
vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetRenderWindow(renderWindow);

// Add the actors to the scene

renderWindow->Render();

renderWindowInteractor->Start();

return EXIT_SUCCESS;
}


CMakeLists.txt¶

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(ResamplePolyLine)

find_package(VTK COMPONENTS
vtkCommonComputationalGeometry
vtkCommonCore
vtkCommonDataModel
vtkFiltersCore
vtkFiltersGeneral
vtkIOXML
vtkInteractionStyle
vtkRenderingCore
vtkRenderingFreeType
vtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
message("Skipping ResamplePolyLine: ${VTK_NOT_FOUND_MESSAGE}") return () endif() message (STATUS "VTK_VERSION:${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
# old system
include(${VTK_USE_FILE}) add_executable(ResamplePolyLine MACOSX_BUNDLE ResamplePolyLine.cxx ) target_link_libraries(ResamplePolyLine PRIVATE${VTK_LIBRARIES})
else ()
# include all components
target_link_libraries(ResamplePolyLine PRIVATE ${VTK_LIBRARIES}) # vtk_module_autoinit is needed vtk_module_autoinit( TARGETS ResamplePolyLine MODULES${VTK_LIBRARIES}
)
endif ()


cd ResamplePolyLine/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:

./ResamplePolyLine


WINDOWS USERS

Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.