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ImageDataGeometryFilter

vtk-examples/Cxx/ImageData/ImageDataGeometryFilter


Description

Convert a vtkImageData to a vtkPolyData.

Other languages

See (Python)

Question

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Code

ImageDataGeometryFilter.cxx

#include <vtkActor.h>
#include <vtkImageCanvasSource2D.h>
#include <vtkImageData.h>
#include <vtkImageDataGeometryFilter.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSphereSource.h>

#include <array>

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

  // 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};
  for (auto i = 0; i < 4; ++i)
  {
    sourceColor1[i] = color1[i];
    sourceColor2[i] = color2[i];
  }

  // Create an image
  vtkNew<vtkImageCanvasSource2D> source1;
  source1->SetScalarTypeToUnsignedChar();
  source1->SetNumberOfScalarComponents(3);
  source1->SetExtent(0, 100, 0, 100, 0, 0);
  source1->SetDrawColor(sourceColor1.data());
  source1->FillBox(0, 100, 0, 100);
  source1->SetDrawColor(sourceColor2.data());
  source1->FillBox(10, 20, 10, 20);
  source1->FillBox(40, 50, 20, 30);
  source1->Update();

  // Convert the image to a polydata
  vtkNew<vtkImageDataGeometryFilter> imageDataGeometryFilter;
  imageDataGeometryFilter->SetInputConnection(source1->GetOutputPort());
  imageDataGeometryFilter->Update();

  // Create a mapper and actor
  vtkNew<vtkPolyDataMapper> mapper;
  mapper->SetInputConnection(imageDataGeometryFilter->GetOutputPort());

  vtkNew<vtkActor> actor;
  actor->SetMapper(mapper);

  // Visualization
  vtkNew<vtkRenderer> renderer;
  vtkNew<vtkRenderWindow> renderWindow;
  renderWindow->AddRenderer(renderer);
  vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
  renderWindowInteractor->SetRenderWindow(renderWindow);

  renderer->AddActor(actor);
  renderer->SetBackground(colors->GetColor3d("RosyBrown").GetData());

  renderWindow->SetWindowName("ImageDataGeometryFilter");
  renderWindow->Render();
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(ImageDataGeometryFilter)

find_package(VTK COMPONENTS 
  vtkCommonColor
  vtkCommonCore
  vtkCommonDataModel
  vtkFiltersGeometry
  vtkFiltersSources
  vtkImagingSources
  vtkInteractionStyle
  vtkRenderingContextOpenGL2
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingGL2PSOpenGL2
  vtkRenderingOpenGL2
  QUIET
)

if (NOT VTK_FOUND)
  message("Skipping ImageDataGeometryFilter: ${VTK_NOT_FOUND_MESSAGE}")
  return ()
endif()
message (STATUS "VTK_VERSION: ${VTK_VERSION}")
if (VTK_VERSION VERSION_LESS "8.90.0")
  # old system
  include(${VTK_USE_FILE})
  add_executable(ImageDataGeometryFilter MACOSX_BUNDLE ImageDataGeometryFilter.cxx )
  target_link_libraries(ImageDataGeometryFilter PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(ImageDataGeometryFilter MACOSX_BUNDLE ImageDataGeometryFilter.cxx )
  target_link_libraries(ImageDataGeometryFilter PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS ImageDataGeometryFilter
    MODULES ${VTK_LIBRARIES}
    )
endif ()

Download and Build ImageDataGeometryFilter

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

cd ImageDataGeometryFilter/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:

./ImageDataGeometryFilter

WINDOWS USERS

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