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DrawShapes

vtk-examples/Cxx/Images/DrawShapes


Question

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Code

DrawShapes.cxx

#include <vtkImageCanvasSource2D.h>
#include <vtkImageData.h>
#include <vtkImageViewer2.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>

#include <array>

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

  std::array<double, 3> drawColor1{0, 0, 0};
  auto color1 = colors->GetColor3ub("DimGray").GetData();
  std::array<double, 3> drawColor2{0, 0, 0};
  auto color2 = colors->GetColor3ub("HotPink").GetData();
  for (auto i = 0; i < 3; ++i)
  {
    drawColor1[i] = color1[i];
    drawColor2[i] = color2[i];
  }

  // Create a blank, colored image
  vtkNew<vtkImageCanvasSource2D> drawing;
  drawing->SetScalarTypeToUnsignedChar();
  drawing->SetNumberOfScalarComponents(3);
  drawing->SetExtent(0, 20, 0, 50, 0, 0);
  // Comment out or set color1 to "Black" if you want a black image
  drawing->SetDrawColor(drawColor1.data());
  drawing->FillBox(0, 20, 0, 50);

  // Draw a red circle of radius 5 centered at (9,10)
  drawing->SetDrawColor(drawColor2.data());
  drawing->DrawCircle(9, 10, 5);
  drawing->Update();

  // View the result
  vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
  vtkNew<vtkImageViewer2> imageViewer;
  imageViewer->SetInputConnection(drawing->GetOutputPort());
  imageViewer->SetupInteractor(renderWindowInteractor);
  imageViewer->GetRenderer()->GradientBackgroundOn();
  imageViewer->GetRenderer()->SetBackground(
      colors->GetColor3d("SkyBlue").GetData());
  imageViewer->GetRenderer()->SetBackground2(
      colors->GetColor3d("MidnightBlue").GetData());
  imageViewer->GetRenderer()->ResetCamera();
  imageViewer->GetRenderWindow()->SetWindowName("DrawShapes");
  imageViewer->GetRenderWindow()->Render();
  renderWindowInteractor->Initialize();
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(DrawShapes)

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

if (NOT VTK_FOUND)
  message("Skipping DrawShapes: ${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(DrawShapes MACOSX_BUNDLE DrawShapes.cxx )
  target_link_libraries(DrawShapes PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(DrawShapes MACOSX_BUNDLE DrawShapes.cxx )
  target_link_libraries(DrawShapes PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS DrawShapes
    MODULES ${VTK_LIBRARIES}
    )
endif ()

Download and Build DrawShapes

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

cd DrawShapes/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:

./DrawShapes

WINDOWS USERS

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