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.
Code
ResamplePolyLine.cxx
#include <vtkVersion.h>
#include <vtkSmartPointer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkActor.h>
#include <vtkPolyDataMapper.h>
#include <vtkXMLPolyDataReader.h>
#include <vtkPoints.h>
#include <vtkMath.h>
#include <vtkSplineFilter.h>
#include <vtkSphereSource.h>
#include <vtkGlyph3D.h>
#include <vtkProperty.h>
#include <vtkCellArray.h>
#include <vtkCardinalSpline.h>
int main (int argc, char *argv[])
{
vtkSmartPointer<vtkPolyData> polyData =
vtkSmartPointer<vtkPolyData>::New();
if (argc > 1)
{
vtkSmartPointer<vtkXMLPolyDataReader> reader =
vtkSmartPointer<vtkXMLPolyDataReader>::New();
reader->SetFileName ( argv[1] );
reader->Update();
polyData = reader->GetOutput();
}
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();
#if VTK_MAJOR_VERSION <= 5
splineFilter->SetInput(polyData);
#else
splineFilter->SetInputData(polyData);
#endif
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->SetRadius(.04);
originalNodes->SetPhiResolution(10);
originalNodes->SetThetaResolution(10);
vtkSmartPointer<vtkGlyph3D> glyphOriginal =
vtkSmartPointer<vtkGlyph3D>::New();
#if VTK_MAJOR_VERSION <= 5
glyphOriginal->SetInput(polyData);
#else
glyphOriginal->SetInputData(polyData);
#endif
glyphOriginal->SetSourceConnection(originalNodes->GetOutputPort());
vtkSmartPointer<vtkSphereSource> newNodes =
vtkSmartPointer<vtkSphereSource>::New();
newNodes->SetRadius(.02);
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();
renderWindow->AddRenderer(renderer);
// An interactor
vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
vtkSmartPointer<vtkRenderWindowInteractor>::New();
renderWindowInteractor->SetRenderWindow(renderWindow);
// Add the actors to the scene
renderer->AddActor(originalActor);
renderer->AddActor(newActor);
renderer->AddActor(splineActor);
renderWindow->Render();
renderWindowInteractor->Start();
return EXIT_SUCCESS;
}
CMakeLists.txt
cmake_minimum_required(VERSION 2.8)
PROJECT(ResamplePolyLine)
find_package(VTK REQUIRED)
include(${VTK_USE_FILE})
add_executable(ResamplePolyLine MACOSX_BUNDLE ResamplePolyLine.cxx)
target_link_libraries(ResamplePolyLine ${VTK_LIBRARIES})
Download and Build ResamplePolyLine
Click here to download ResamplePolyLine and its CMakeLists.txt file. Once the tarball ResamplePolyLine.tar has been downloaded and extracted,
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 PLEASE NOTE: Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.