WikiExamples/SimpleOperations/SetPixels.cxx

#include "itkImage.h"

#include <itkImageToVTKImageFilter.h>

#include "vtkVersion.h"
#include "vtkImageViewer.h"
#include "vtkImageMapper3D.h"
#include "vtkRenderWindowInteractor.h"
#include "vtkSmartPointer.h"
#include "vtkImageActor.h"
#include "vtkInteractorStyleImage.h"
#include "vtkRenderer.h"

int main(int, char *[])
{
  using ImageType = itk::Image< unsigned char, 2 >;

  ImageType::RegionType region;
  ImageType::IndexType start;
  start[0] = 0;
  start[1] = 0;

  ImageType::SizeType size;
  size[0] = 200;
  size[1] = 300;

  region.SetSize(size);
  region.SetIndex(start);

  ImageType::Pointer image = ImageType::New();
  image->SetRegions(region);
  image->Allocate();

  // Set pixels in a square to one value
  for(unsigned int r = 20; r < 80; r++)
  {
      for(unsigned int c = 30; c < 100; c++)
      {
          ImageType::IndexType pixelIndex;
          pixelIndex[0] = r;
          pixelIndex[1] = c;

          image->SetPixel(pixelIndex, 255);
      }
  }

  // Set pixels in a different square to a different value
  for(unsigned int r = 100; r < 130; r++)
  {
      for(unsigned int c = 115; c < 160; c++)
      {
          ImageType::IndexType pixelIndex;
          pixelIndex[0] = r;
          pixelIndex[1] = c;

          image->SetPixel(pixelIndex, 125);
      }
  }

  using ConnectorType = itk::ImageToVTKImageFilter<ImageType>;
  ConnectorType::Pointer connector = ConnectorType::New();
  connector->SetInput(image);
  
  vtkSmartPointer<vtkImageActor> actor =
    vtkSmartPointer<vtkImageActor>::New();
#if VTK_MAJOR_VERSION <= 5
  actor->SetInput(connector->GetOutput());
#else
  connector->Update();  
  actor->GetMapper()->SetInputData(connector->GetOutput());
#endif

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

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

  vtkSmartPointer<vtkRenderer> renderer =
    vtkSmartPointer<vtkRenderer>::New();
  renderWindow->AddRenderer(renderer);

  renderer->AddActor(actor);

  renderer->ResetCamera();

  renderWindow->Render();

  vtkSmartPointer<vtkInteractorStyleImage> style =
    vtkSmartPointer<vtkInteractorStyleImage>::New();

  interactor->SetInteractorStyle(style);

  interactor->Start();

  return EXIT_SUCCESS;
}