#include <vtkSphereSource.h>
#include <vtkProperty.h>
#include <vtkPolyData.h>
#include <vtkSmartPointer.h>
#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>

int main(int, char *[])
{
  vtkSmartPointer<vtkRenderWindow> renderWindow =
    vtkSmartPointer<vtkRenderWindow>::New();

  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
    vtkSmartPointer<vtkRenderWindowInteractor>::New();

  renderWindowInteractor->SetRenderWindow(renderWindow);

  // Define viewport ranges
  double xmins[4] = {0,.5,0,.5};
  double xmaxs[4] = {0.5,1,0.5,1};
  double ymins[4] = {0,0,.5,.5};
  double ymaxs[4]= {0.5,0.5,1,1};
  for(unsigned i = 0; i < 4; i++)
  {
    vtkSmartPointer<vtkRenderer> renderer =
      vtkSmartPointer<vtkRenderer>::New();

    renderWindow->AddRenderer(renderer);
    renderer->SetViewport(xmins[i],ymins[i],xmaxs[i],ymaxs[i]);

    // Create a sphere
    vtkSmartPointer<vtkSphereSource> sphereSource =
      vtkSmartPointer<vtkSphereSource>::New();
    sphereSource->SetCenter(0.0, 0.0, 0.0);
    sphereSource->SetRadius(5);
    sphereSource->Update();

    // Create a mapper and actor
    vtkSmartPointer<vtkPolyDataMapper> mapper =
      vtkSmartPointer<vtkPolyDataMapper>::New();
    mapper->SetInputConnection(sphereSource->GetOutputPort());
    vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();
    actor->SetMapper(mapper);
    renderer->AddActor(actor);
    renderer->ResetCamera();

    renderWindow->Render();
    renderWindow->SetWindowName("Multiple ViewPorts");
  }

  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}
