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HideActor

vtk-examples/Cxx/Visualization/HideActor

Description

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

Question

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

Code

HideActor.cxx

#include <vtkActor.h>
#include <vtkInteractorStyleSwitch.h>
#include <vtkNamedColors.h>
#include <vtkNew.h>
#include <vtkPolyDataMapper.h>
#include <vtkPropCollection.h>
#include <vtkProperty.h>
#include <vtkRenderWindow.h>
#include <vtkRenderWindowInteractor.h>
#include <vtkRenderer.h>
#include <vtkSphereSource.h>

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

  // Sphere 1
  vtkNew<vtkSphereSource> sphereSource1;
  sphereSource1->SetCenter(0.0, 0.0, 0.0);
  sphereSource1->SetRadius(4.0);
  sphereSource1->Update();

  vtkNew<vtkPolyDataMapper> mapper1;
  mapper1->SetInputConnection(sphereSource1->GetOutputPort());

  vtkNew<vtkActor> actor1;
  actor1->SetMapper(mapper1);
  actor1->GetProperty()->SetColor(colors->GetColor3d("MistyRose").GetData());

  // Sphere 2
  vtkNew<vtkSphereSource> sphereSource2;
  sphereSource2->SetCenter(10.0, 0.0, 0.0);
  sphereSource2->SetRadius(3.0);
  sphereSource2->Update();

  // Create a mapper.
  vtkNew<vtkPolyDataMapper> mapper2;
  mapper2->SetInputConnection(sphereSource2->GetOutputPort());

  // Create an actor.
  vtkNew<vtkActor> actor2;
  actor2->SetMapper(mapper2);
  actor2->GetProperty()->SetColor(colors->GetColor3d("Honeydew").GetData());

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

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

  // Add the actors to the scene.
  renderer->AddActor(actor1);
  renderer->AddActor(actor2);
  renderer->SetBackground(colors->GetColor3d("LightSlateGray").GetData());

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

  vtkNew<vtkInteractorStyleSwitch> style;

  renderWindowInteractor->SetInteractorStyle(style);
  // renderWindowInteractor->Start();

  // Change the background color so we know we are done with the original two
  // sphere display.
  renderer->SetBackground(colors->GetColor3d("DarkSlateGray").GetData());

  // 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 3.12 FATAL_ERROR)

project(HideActor)

find_package(VTK COMPONENTS 
  CommonColor
  CommonCore
  FiltersSources
  InteractionStyle
  RenderingContextOpenGL2
  RenderingCore
  RenderingFreeType
  RenderingGL2PSOpenGL2
  RenderingOpenGL2
)

if (NOT VTK_FOUND)
  message(FATAL_ERROR "HideActor: Unable to find the VTK build folder.")
endif()

# Prevent a "command line is too long" failure in Windows.
set(CMAKE_NINJA_FORCE_RESPONSE_FILE "ON" CACHE BOOL "Force Ninja to use response files.")
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}
)

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.