VTK/Examples/Cxx/PolyData/ExtractPolyLinesFromPolyData

#include <vtkSmartPointer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkActor.h>
#include <vtkProperty.h>
#include <vtkPolyDataMapper.h>
#include <vtkStripper.h>
#include <vtkCutter.h>
#include <vtkPlane.h>
#include <vtkSphereSource.h>
#include <vtkPoints.h>
#include <vtkCellArray.h>
 
int main (int, char *[])
{
  vtkSmartPointer<vtkSphereSource> modelSource =
    vtkSmartPointer<vtkSphereSource>::New();
 
  vtkSmartPointer<vtkPlane> plane =
    vtkSmartPointer<vtkPlane>::New();
 
  vtkSmartPointer<vtkCutter> cutter =
    vtkSmartPointer<vtkCutter>::New();
  cutter->SetInputConnection(modelSource->GetOutputPort());
  cutter->SetCutFunction(plane);
  cutter->GenerateValues(10, -.5, .5);
 
  vtkSmartPointer<vtkPolyDataMapper> modelMapper =
    vtkSmartPointer<vtkPolyDataMapper>::New();
  modelMapper->SetInputConnection(modelSource->GetOutputPort());
 
  vtkSmartPointer<vtkActor> model =
    vtkSmartPointer<vtkActor>::New();
  model->SetMapper(modelMapper);
 
  vtkSmartPointer<vtkStripper> stripper =
    vtkSmartPointer<vtkStripper>::New();
  stripper->SetInputConnection(cutter->GetOutputPort());
 
  vtkSmartPointer<vtkPolyDataMapper> linesMapper =
    vtkSmartPointer<vtkPolyDataMapper>::New();
  linesMapper->SetInputConnection(stripper->GetOutputPort());
 
  vtkSmartPointer<vtkActor> lines =
    vtkSmartPointer<vtkActor>::New();
  lines->SetMapper(linesMapper);
  lines->GetProperty()->SetDiffuseColor(.2, .2, .2);
 
  vtkSmartPointer<vtkRenderer> ren =
    vtkSmartPointer<vtkRenderer>::New();
  vtkSmartPointer<vtkRenderWindow> renWin =
    vtkSmartPointer<vtkRenderWindow>::New();
 
  renWin->AddRenderer(ren);
 
  vtkSmartPointer<vtkRenderWindowInteractor> iren =
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  iren->SetRenderWindow(renWin);
 
  // Add the actors to the renderer
  ren->AddActor(model);
  ren->AddActor(lines);
  ren->SetBackground(0.1, 0.2, 0.4);
 
  // This starts the event loop and as a side effect causes an initial
  // render.
  renWin->Render();
  iren->Start();
 
 
  // Extract the lines from the polydata
  vtkIdType numberOfLines = cutter->GetOutput()->GetNumberOfLines();
 
 
  std::cout << "-----------Lines without using vtkStripper" << std::endl;
  std::cout << "There are "
            << numberOfLines
            << " lines in the polydata" << std::endl;
 
  numberOfLines = stripper->GetOutput()->GetNumberOfLines();
  vtkPoints *points = stripper->GetOutput()->GetPoints();
  vtkCellArray *cells = stripper->GetOutput()->GetLines();
 
  std::cout << "-----------Lines using vtkStripper" << std::endl;
  std::cout << "There are "
            << numberOfLines
            << " lines in the polydata" << std::endl;
 
  vtkIdType *indices;
  vtkIdType numberOfPoints;
  unsigned int lineCount = 0;
  for (cells->InitTraversal();
       cells->GetNextCell(numberOfPoints, indices);
       lineCount++)
    {
    std::cout << "Line " << lineCount << ": " << std::endl;
    for (vtkIdType i = 0; i < numberOfPoints; i++)
      {
      double point[3];
      points->GetPoint(indices[i], point);
      std::cout << "\t("
                << point[0] << ", "
                << point[1] << ", "
                << point[2] << ")" << std::endl;
      }
    }
  return EXIT_SUCCESS;
}