CompassWidget

VTKExamples/Cxx/Geovis/CompassWidget

Description¶

This example creates a compass in the top right corner of the window.

Other Languages

Code¶

CompassWidget.cxx

#include <vtkPolyDataMapper.h>
#include <vtkActor.h>
#include <vtkRenderWindow.h>
#include <vtkRenderer.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkPolyData.h>
#include <vtkSmartPointer.h>
#include <vtkSphereSource.h>
#include <vtkCompassWidget.h>
#include <vtkCompassRepresentation.h>
#include <vtkInteractorStyleTrackballCamera.h>
#include <vtkInteractorStyleTrackball.h>

int main (int, char *[])
{

  //sphere 1
  vtkSmartPointer<vtkSphereSource> sphereSource = 
    vtkSmartPointer<vtkSphereSource>::New();
  sphereSource->SetCenter(0.0, 0.0, 0.0);
  sphereSource->SetRadius(4.0);

  vtkSmartPointer<vtkPolyDataMapper> mapper = 
    vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper->SetInputConnection(sphereSource->GetOutputPort());

  vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();
  actor->SetMapper(mapper);

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

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

  // Create the widget and its representation
  vtkSmartPointer<vtkCompassRepresentation> compassRepresentation = vtkSmartPointer<vtkCompassRepresentation>::New();

  vtkSmartPointer<vtkCompassWidget> compassWidget = 
    vtkSmartPointer<vtkCompassWidget>::New();
  compassWidget->SetInteractor(renderWindowInteractor);
  compassWidget->SetRepresentation(compassRepresentation);

  // add the actors to the scene
  renderer->AddActor(actor);
  renderer->SetBackground(1,1,1); // Background color white
  renderWindow->Render();
  compassWidget->EnabledOn();

  vtkSmartPointer<vtkInteractorStyleTrackballCamera> style = 
      vtkSmartPointer<vtkInteractorStyleTrackballCamera>::New();   
  renderWindowInteractor->SetInteractorStyle( style );

  // begin interaction
  renderWindowInteractor->Start();

  return EXIT_SUCCESS;
}

CMakeLists.txt¶

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(CompassWidget)

find_package(VTK COMPONENTS 
  vtkCommonCore
  vtkCommonDataModel
  vtkFiltersSources
  vtkGeovisCore
  vtkInteractionStyle
  vtkRenderingCore
  vtkRenderingFreeType
  vtkRenderingOpenGL2 QUIET)
if (NOT VTK_FOUND)
  message("Skipping CompassWidget: ${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(CompassWidget MACOSX_BUNDLE CompassWidget.cxx )
  target_link_libraries(CompassWidget PRIVATE ${VTK_LIBRARIES})
else ()
  # include all components
  add_executable(CompassWidget MACOSX_BUNDLE CompassWidget.cxx )
  target_link_libraries(CompassWidget PRIVATE ${VTK_LIBRARIES})
  # vtk_module_autoinit is needed
  vtk_module_autoinit(
    TARGETS CompassWidget
    MODULES ${VTK_LIBRARIES}
    )
endif ()

Download and Build CompassWidget¶

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

cd CompassWidget/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:

./CompassWidget

WINDOWS USERS

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