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WriteBMP

vtk-examples/Cxx/IO/WriteBMP

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Code

WriteBMP.cxx

#include <vtkBMPReader.h>
#include <vtkBMPWriter.h>
#include <vtkImageActor.h>
#include <vtkImageCanvasSource2D.h>
#include <vtkImageMapper3D.h>
#include <vtkInteractorStyleImage.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>

#include <array>

int main(int argc, char* argv[])
{
  vtkNew<vtkNamedColors> colors;

  if (argc != 2)
  {
    std::cout << "Required parameters: OutputFilename.bmp" << std::endl;
    return EXIT_FAILURE;
  }

  std::string filename = argv[1];

  // Convert our unsigned char colors to doubles.
  // Set draw color needs doubles.
  auto color1 = colors->GetColor4ub("SteelBlue").GetData();
  auto color2 = colors->GetColor4ub("PaleGoldenrod").GetData();
  std::array<double, 4> sourceColor1{0, 0, 0, 0};
  std::array<double, 4> sourceColor2{0, 0, 0, 0};
  // Leave alpha at zero.
  for (auto i = 0; i < 3; ++i)
  {
    sourceColor1[i] = color1[i];
    sourceColor2[i] = color2[i];
  }

  vtkNew<vtkImageCanvasSource2D> imageSource;
  imageSource->SetScalarTypeToUnsignedChar();
  imageSource->SetExtent(0, 9, 0, 9, 0, 0);
  imageSource->SetNumberOfScalarComponents(3);
  imageSource->SetDrawColor(sourceColor1.data());
  imageSource->FillBox(0, 9, 0, 9);
  imageSource->SetDrawColor(sourceColor2.data());
  imageSource->FillBox(5, 7, 5, 7);
  imageSource->Update();

  vtkNew<vtkBMPWriter> bmpWriter;
  bmpWriter->SetFileName(filename.c_str());
  bmpWriter->SetInputConnection(imageSource->GetOutputPort());
  bmpWriter->Write();

  // Read and display for verification.
  vtkNew<vtkBMPReader> reader;
  reader->SetFileName(filename.c_str());
  reader->Update();

  vtkNew<vtkImageActor> actor;
  actor->GetMapper()->SetInputConnection(reader->GetOutputPort());

  // Setup renderer.
  vtkNew<vtkRenderer> renderer;
  renderer->AddActor(actor);
  renderer->SetBackground(colors->GetColor3d("DarkSlateGray").GetData());
  renderer->ResetCamera();

  // Setup render window.
  vtkNew<vtkRenderWindow> renderWindow;
  renderWindow->AddRenderer(renderer);
  renderWindow->SetWindowName("WriteBMP");

  // Setup render window interactor.
  vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
  vtkNew<vtkInteractorStyleImage> style;

  renderWindowInteractor->SetInteractorStyle(style);

  // Render and start interaction.
  renderWindowInteractor->SetRenderWindow(renderWindow);
  renderWindow->Render();
  renderWindowInteractor->Initialize();

  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)

project(WriteBMP)

find_package(VTK COMPONENTS 
  CommonColor
  CommonCore
  IOImage
  ImagingSources
  InteractionStyle
  RenderingContextOpenGL2
  RenderingCore
  RenderingFreeType
  RenderingGL2PSOpenGL2
  RenderingOpenGL2
)

if (NOT VTK_FOUND)
  message(FATAL_ERROR "WriteBMP: Unable to find the VTK build folder.")
endif()

# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
add_executable(WriteBMP MACOSX_BUNDLE WriteBMP.cxx )
  target_link_libraries(WriteBMP PRIVATE ${VTK_LIBRARIES}
)
# vtk_module_autoinit is needed
vtk_module_autoinit(
  TARGETS WriteBMP
  MODULES ${VTK_LIBRARIES}
)

Download and Build WriteBMP

Click here to download WriteBMP and its CMakeLists.txt file. Once the tarball WriteBMP.tar has been downloaded and extracted,

cd WriteBMP/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:

./WriteBMP

WINDOWS USERS

Be sure to add the VTK bin directory to your path. This will resolve the VTK dll's at run time.