BillboardTextActor3D

VTKEx/Cxx/Visualization/BillboardTextActor3D

Question

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Code

BillboardTextActor3D.cxx

#include <vtkSmartPointer.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkPolyData.h>
#include <vtkSphereSource.h>
#include <vtkBillboardTextActor3D.h>
#include <vtkTextProperty.h>
#include <vtkCallbackCommand.h>
#include <vtkMath.h>
#include <sstream>

void ActorCallback( vtkObject* caller,
                      long unsigned int vtkNotUsed(eventId),
                      void* clientData,
                      void* vtkNotUsed(callData) )
{
  vtkSmartPointer<vtkBillboardTextActor3D> textActor = 
    static_cast<vtkBillboardTextActor3D *>(clientData);
  vtkSmartPointer<vtkActor> actor = 
    static_cast<vtkActor *>(caller);
  std::ostringstream label;
  label << std::setprecision(3)
        << actor->GetPosition()[0] << ", "
       << actor->GetPosition()[1] << ", "
       << actor->GetPosition()[2] << std::endl;
  textActor->SetPosition(actor->GetPosition());
  textActor->SetInput(label.str().c_str());
}

int main(int, char *[])
{
  // For testing
  vtkMath::RandomSeed(8775070);

  // Create a sphere
  vtkSmartPointer<vtkSphereSource> sphereSource = 
    vtkSmartPointer<vtkSphereSource>::New();
  sphereSource->SetCenter ( 0.0, 0.0, 0.0 );
  sphereSource->SetRadius ( 1.0 );

  // Create an actor
  vtkSmartPointer<vtkPolyDataMapper> mapper2 = 
    vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper2->SetInputConnection ( sphereSource->GetOutputPort() );
  vtkSmartPointer<vtkActor> actor2 = 
    vtkSmartPointer<vtkActor>::New();
  actor2->SetMapper ( mapper2 );
  actor2->SetPosition(0, 0, 0);
  actor2->GetProperty()->SetColor(1.0, .4, .4);

  // Create a renderer
  vtkSmartPointer<vtkRenderer> renderer = 
    vtkSmartPointer<vtkRenderer>::New();
  renderer->SetBackground ( .6, .4, .2);
  renderer->AddActor ( actor2 );

  // Create a render window
  vtkSmartPointer<vtkRenderWindow> renderWindow = 
    vtkSmartPointer<vtkRenderWindow>::New();
  renderWindow->AddRenderer ( renderer );

  // Create an interactor
  vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = 
    vtkSmartPointer<vtkRenderWindowInteractor>::New();
  renderWindowInteractor->SetRenderWindow ( renderWindow );

  for (int i = 0; i < 10; ++i)
  {
    // Create a mapper
    vtkSmartPointer<vtkPolyDataMapper> mapper = 
      vtkSmartPointer<vtkPolyDataMapper>::New();
    mapper->SetInputConnection ( sphereSource->GetOutputPort() );

    // Create an actor
    vtkSmartPointer<vtkActor> actor = 
      vtkSmartPointer<vtkActor>::New();
    actor->SetMapper ( mapper );
    actor->SetPosition(0, 0, 0);

    // Setup the text and add it to the renderer
    vtkSmartPointer<vtkBillboardTextActor3D> textActor = 
      vtkSmartPointer<vtkBillboardTextActor3D>::New();
    textActor->SetInput ("");
    textActor->SetPosition (actor->GetPosition());
    textActor->GetTextProperty()->SetFontSize ( 12 );
    textActor->GetTextProperty()->SetColor ( 1.0, 1.0, .4 );
    textActor->GetTextProperty()->SetJustificationToCentered();

    renderer->AddActor ( actor );
    renderer->AddActor ( textActor );

    vtkSmartPointer<vtkCallbackCommand> actorCallback =
      vtkSmartPointer<vtkCallbackCommand>::New();
    actorCallback->SetCallback (ActorCallback);
    actorCallback->SetClientData(textActor);
    actor->AddObserver(vtkCommand::ModifiedEvent,actorCallback);
    actor->SetPosition(vtkMath::Random(-10.0, 10.0),
                       vtkMath::Random(-10.0, 10.0),
                       vtkMath::Random(-10.0, 10.0));
  }
  renderWindow->Render();
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(BillboardTextActor3D)

find_package(VTK COMPONENTS 
  vtkvtkCommonCore
  vtkvtkCommonDataModel
  vtkvtkFiltersSources
  vtkvtkInteractionStyle
  vtkvtkRenderingContextOpenGL2
  vtkvtkRenderingCore
  vtkvtkRenderingFreeType
  vtkvtkRenderingGL2PSOpenGL2
  vtkvtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
  message("Skipping BillboardTextActor3D: ${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(BillboardTextActor3D MACOSX_BUNDLE BillboardTextActor3D.cxx )
  target_link_libraries(BillboardTextActor3D PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(BillboardTextActor3D MACOSX_BUNDLE BillboardTextActor3D.cxx )
  target_link_libraries(BillboardTextActor3D PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS BillboardTextActor3D
    MODULES ${VTK_LIBRARIES}
    )
endif ()

Download and Build BillboardTextActor3D

Click here to download BillboardTextActor3D and its CMakeLists.txt file. Once the tarball BillboardTextActor3D.tar has been downloaded and extracted,

cd BillboardTextActor3D/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:

./BillboardTextActor3D

WINDOWS USERS

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