HideActor

VTKExamples/Cxx/Visualization/HideActor

Description

Display two spheres, then hide one, then hide both.

Question

If you have a simple question about this example contact us at VTKExamplesProject If your question is more complex and may require extended discussion, please use the VTK Discourse Forum

Code

HideActor.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 <vtkPropCollection.h>
#include <vtkInteractorStyleTrackballCamera.h>
#include <vtkInteractorStyleTrackball.h>

int main (int, char *[])
{
  // Sphere 1
  vtkSmartPointer<vtkSphereSource> sphereSource1 =
    vtkSmartPointer<vtkSphereSource>::New();
  sphereSource1->SetCenter(0.0, 0.0, 0.0);
  sphereSource1->SetRadius(4.0);
  sphereSource1->Update();

  vtkSmartPointer<vtkPolyDataMapper> mapper1 =
    vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper1->SetInputConnection(sphereSource1->GetOutputPort());

  vtkSmartPointer<vtkActor> actor1 =
    vtkSmartPointer<vtkActor>::New();
  actor1->SetMapper(mapper1);

  // Sphere 2
  vtkSmartPointer<vtkSphereSource> sphereSource2 =
    vtkSmartPointer<vtkSphereSource>::New();
  sphereSource2->SetCenter(10.0, 0.0, 0.0);
  sphereSource2->SetRadius(3.0);
  sphereSource2->Update();

  // Create a mapper
  vtkSmartPointer<vtkPolyDataMapper> mapper2 =
    vtkSmartPointer<vtkPolyDataMapper>::New();
  mapper2->SetInputConnection(sphereSource2->GetOutputPort());

  // Create an actor
  vtkSmartPointer<vtkActor> actor2 =
    vtkSmartPointer<vtkActor>::New();
  actor2->SetMapper(mapper2);

  // 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);

  // Add the actors to the scene
  renderer->AddActor(actor1);
  renderer->AddActor(actor2);
  renderer->SetBackground(1,1,1); // Background color white

  // Render an image (lights and cameras are created automatically)
  renderWindow->Render();

  vtkSmartPointer<vtkInteractorStyleTrackballCamera> style =
    vtkSmartPointer<vtkInteractorStyleTrackballCamera>::New(); //like paraview

  renderWindowInteractor->SetInteractorStyle( style );

  renderWindowInteractor->Start();

  // Set the background to red so we know we are done with the original two sphere display
  renderer->SetBackground(1,0,0);

  // Hide one actor at a time
  vtkPropCollection* props = renderer->GetViewProps(); //iterate through and set each visibility to 0
  props->InitTraversal();
  for(int i = 0; i < props->GetNumberOfItems(); i++)
  {
    props->GetNextProp()->VisibilityOff();

    renderer->ResetCamera();
    renderWindow->Render();

    renderWindowInteractor->Start();
  }

  return EXIT_SUCCESS;
}

CMakeLists.txt

cmake_minimum_required(VERSION 3.3 FATAL_ERROR)

project(HideActor)

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

Download and Build HideActor

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

cd HideActor/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:

./HideActor

WINDOWS USERS

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