VTK/Examples/Cxx/PolyData/DownsamplePointCloud

#include <vtkSmartPointer.h>
#include <vtkPointSource.h>
#include <vtkPolyData.h>
#include <vtkCleanPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
 
int main(int, char *[])
{
  vtkSmartPointer<vtkPointSource> pointSource =
    vtkSmartPointer<vtkPointSource>::New();
  pointSource->SetNumberOfPoints(1000);
  pointSource->SetRadius(1.0);
  pointSource->Update();
 
  vtkSmartPointer<vtkCleanPolyData> cleanPolyData =
    vtkSmartPointer<vtkCleanPolyData>::New();
  cleanPolyData->SetInputConnection(pointSource->GetOutputPort());
  cleanPolyData->SetTolerance(0.1);
  cleanPolyData->Update();
 
  vtkSmartPointer<vtkPolyDataMapper> inputMapper =
    vtkSmartPointer<vtkPolyDataMapper>::New();
  inputMapper->SetInputConnection(pointSource->GetOutputPort());
  vtkSmartPointer<vtkActor> inputActor =
    vtkSmartPointer<vtkActor>::New();
  inputActor->SetMapper(inputMapper);
 
  vtkSmartPointer<vtkPolyDataMapper> cleanedMapper =
    vtkSmartPointer<vtkPolyDataMapper>::New();
  cleanedMapper->SetInputConnection(cleanPolyData->GetOutputPort());
  vtkSmartPointer<vtkActor> cleanedActor =
    vtkSmartPointer<vtkActor>::New();
  cleanedActor->SetMapper(cleanedMapper);
 
   // There will be one render window
  vtkSmartPointer<vtkRenderWindow> renderWindow =
    vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->SetSize(600, 300);
 
  // And one interactor
  vtkSmartPointer<vtkRenderWindowInteractor> interactor =
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  interactor->SetRenderWindow(renderWindow);
 
  // Define viewport ranges
  // (xmin, ymin, xmax, ymax)
  double leftViewport[4] = {0.0, 0.0, 0.5, 1.0};
  double rightViewport[4] = {0.5, 0.0, 1.0, 1.0};
 
  // Setup both renderers
  vtkSmartPointer<vtkRenderer> leftRenderer =
    vtkSmartPointer<vtkRenderer>::New();
  renderWindow->AddRenderer(leftRenderer);
  leftRenderer->SetViewport(leftViewport);
  leftRenderer->SetBackground(.6, .5, .4);
 
  vtkSmartPointer<vtkRenderer> rightRenderer =
    vtkSmartPointer<vtkRenderer>::New();
  renderWindow->AddRenderer(rightRenderer);
  rightRenderer->SetViewport(rightViewport);
  rightRenderer->SetBackground(.4, .5, .6);
 
  leftRenderer->AddActor(inputActor);
  rightRenderer->AddActor(cleanedActor);
 
  leftRenderer->ResetCamera();
  rightRenderer->ResetCamera();
 
  renderWindow->Render();
  interactor->Start();
 
  return EXIT_SUCCESS;
}