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GeometricObjectsDemo

vtk-examples/Cxx/GeometricObjects/GeometricObjectsDemo


Other languages

See (Python), (CSharp)

Question

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Code

GeometricObjectsDemo.cxx

#include <vtkActor.h>
#include <vtkActor2D.h>
#include <vtkArrowSource.h>
#include <vtkConeSource.h>
#include <vtkCubeSource.h>
#include <vtkCylinderSource.h>
#include <vtkDiskSource.h>
#include <vtkLineSource.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRegularPolygonSource.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkTextMapper.h>
#include <vtkTextProperty.h>

#include <array>
#include <vector>
#include <vtkCamera.h>

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

  // Set the background color.
  std::array<unsigned char, 4> bkg{{51, 77, 102, 255}};
  colors->SetColor("BkgColor", bkg.data());

  // Create container to hold the 3D object generators (sources)
  std::vector<vtkSmartPointer<vtkPolyDataAlgorithm>> geometricObjectSources;

  // Populate the container with the various object sources to be demonstrated
  geometricObjectSources.push_back(vtkSmartPointer<vtkArrowSource>::New());
  geometricObjectSources.push_back(vtkSmartPointer<vtkConeSource>::New());
  geometricObjectSources.push_back(vtkSmartPointer<vtkCubeSource>::New());
  geometricObjectSources.push_back(vtkSmartPointer<vtkCylinderSource>::New());
  geometricObjectSources.push_back(vtkSmartPointer<vtkDiskSource>::New());
  geometricObjectSources.push_back(vtkSmartPointer<vtkLineSource>::New());
  geometricObjectSources.push_back(
      vtkSmartPointer<vtkRegularPolygonSource>::New());
  geometricObjectSources.push_back(vtkSmartPointer<vtkSphereSource>::New());

  // Create containers for the remaining nodes of each pipeline
  std::vector<vtkSmartPointer<vtkPolyDataMapper>> mappers;
  std::vector<vtkSmartPointer<vtkActor>> actors;
  std::vector<vtkSmartPointer<vtkTextMapper>> textmappers;
  std::vector<vtkSmartPointer<vtkActor2D>> textactors;

  // Create a common text property.
  vtkNew<vtkTextProperty> textProperty;
  textProperty->SetFontSize(16);
  textProperty->SetJustificationToCentered();
  textProperty->SetColor(colors->GetColor3d("LightGoldenrodYellow").GetData());

  // Create a mapper and actor for each object and the corresponding text label
  for (unsigned int i = 0; i < geometricObjectSources.size(); i++)
  {
    geometricObjectSources[i]->Update();

    mappers.push_back(vtkSmartPointer<vtkPolyDataMapper>::New());
    mappers[i]->SetInputConnection(geometricObjectSources[i]->GetOutputPort());

    actors.push_back(vtkSmartPointer<vtkActor>::New());
    actors[i]->SetMapper(mappers[i]);
    actors[i]->GetProperty()->SetColor(
        colors->GetColor3d("PeachPuff").GetData());

    textmappers.push_back(vtkSmartPointer<vtkTextMapper>::New());
    textmappers[i]->SetInput(
        geometricObjectSources[i]->GetClassName()); // set text label to the
                                                    // name of the object source
    textmappers[i]->SetTextProperty(textProperty);

    textactors.push_back(vtkSmartPointer<vtkActor2D>::New());
    textactors[i]->SetMapper(textmappers[i]);
    textactors[i]->SetPosition(120, 16); // Note: the position of an Actor2D is
                                         // specified in display coordinates
  }

  // Define size of the grid that will hold the objects
  int gridCols = 3;
  int gridRows = 3;
  // Define side length (in pixels) of each renderer square
  int rendererSize = 300;

  vtkNew<vtkRenderWindow> renderWindow;
  renderWindow->SetWindowName("GeometricObjectsDemo");
  renderWindow->SetSize(rendererSize * gridCols, rendererSize * gridRows);

  // Set up a grid of viewports for each renderer
  for (double row = 0; row < gridRows; row++)
  {
    for (double col = 0; col < gridCols; col++)
    {
      double index = row * gridCols + col;

      // Create a renderer for this grid cell
      vtkSmartPointer<vtkRenderer> renderer =
          vtkSmartPointer<vtkRenderer>::New();
      renderer->SetBackground(colors->GetColor3d("BkgColor").GetData());

      // Set the renderer's viewport dimensions (xmin, ymin, xmax, ymax) within
      // the render window. Note that for the Y values, we need to subtract the
      // row index from gridRows because the viewport Y axis points upwards, but
      // we want to draw the grid from top to down
      double viewport[4] = {static_cast<double>(col) / gridCols,
                            static_cast<double>(gridRows - row - 1) / gridRows,
                            static_cast<double>(col + 1) / gridCols,
                            static_cast<double>(gridRows - row) / gridRows};
      renderer->SetViewport(viewport);

      // Add the corresponding actor and label for this grid cell, if they exist
      if (index < geometricObjectSources.size())
      {
        renderer->AddActor(actors[index]);
        renderer->AddActor(textactors[index]);
        renderer->ResetCameraClippingRange();
      }

      renderWindow->AddRenderer(renderer);
    }
  }

  vtkNew<vtkRenderWindowInteractor> interactor;
  interactor->SetRenderWindow(renderWindow);

  renderWindow->Render();
  interactor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(GeometricObjectsDemo)

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

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

Download and Build GeometricObjectsDemo

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

cd GeometricObjectsDemo/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:

./GeometricObjectsDemo

WINDOWS USERS

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