Skip to content

TrackballActor

vtk-examples/Cxx/Interaction/TrackballActor


Description

This example shows how to visualize data in "trackball" mode. That is, click and drag actors is the way to interact.

Contrast this with TrackballCamera.

Other languages

See (Java)

Question

If you have a question about this example, please use the VTK Discourse Forum

Code

TrackballActor.cxx

#include <vtkActor.h>
#include <vtkConeSource.h>
#include <vtkInteractorStyleTrackballActor.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyData.h>
#include <vtkPolyDataMapper.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSphereSource.h>

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

  // Create a sphere
  vtkNew<vtkSphereSource> sphereSource;
  sphereSource->SetCenter(1.0, 0.0, 0.0);
  sphereSource->Update();

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

  vtkNew<vtkActor> sphereActor;
  sphereActor->SetMapper(sphereMapper);
  sphereActor->GetProperty()->SetColor(
      colors->GetColor3d("MistyRose").GetData());

  // Create a cone
  vtkNew<vtkConeSource> coneSource;

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

  vtkNew<vtkActor> coneActor;
  coneActor->SetMapper(coneMapper);
  coneActor->GetProperty()->SetColor(
      colors->GetColor3d("LightGoldenrodYellow").GetData());

  // A renderer and render window
  vtkNew<vtkRenderer> renderer;
  vtkNew<vtkRenderWindow> renderWindow;
  renderWindow->AddRenderer(renderer);
  renderWindow->SetWindowName("TrackballActor");

  // An interactor
  vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
  renderWindowInteractor->SetRenderWindow(renderWindow);

  // Add the actors to the scene
  renderer->AddActor(sphereActor);
  renderer->AddActor(coneActor);
  renderer->SetBackground(colors->GetColor3d("SlateGray").GetData());

  // Render
  renderWindow->Render();

  vtkNew<vtkInteractorStyleTrackballActor> style;

  renderWindowInteractor->SetInteractorStyle(style);

  // Begin mouse interaction
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(TrackballActor)

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

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

Download and Build TrackballActor

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

cd TrackballActor/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:

./TrackballActor

WINDOWS USERS

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