# MultipleRenderWindows

VTKExamples/Cxx/Visualization/MultipleRenderWindows

### Description

This example creates 4 render windows. When you close one, the next one opens? Or do they all open simultaneously?

### Code

MultipleRenderWindows.cxx

    #include <vtkSmartPointer.h>

    #include <vtkActor.h>
    #include <vtkPolyData.h>
    #include <vtkPolyDataMapper.h>
    #include <vtkProperty.h>
    #include <vtkRenderWindow.h>
    #include <vtkRenderWindowInteractor.h>
    #include <vtkRenderer.h>
    #include <vtkSphereSource.h>

    #include <sstream>
    #include <vector>

    int main(int, char *[])
    {
      std::vector<vtkSmartPointer<vtkRenderWindowInteractor> > interactors;

      for(unsigned int i = 0; i < 4; i++)
      {
        vtkSmartPointer<vtkRenderWindow> renderWindow =
          vtkSmartPointer<vtkRenderWindow>::New();

        vtkSmartPointer<vtkRenderer> renderer =
          vtkSmartPointer<vtkRenderer>::New();

        renderWindow->AddRenderer(renderer);

        vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =
          vtkSmartPointer<vtkRenderWindowInteractor>::New();

        interactors.push_back(renderWindowInteractor);

        renderWindowInteractor->SetRenderWindow(renderWindow);
        renderWindow->Render();
        std::stringstream ss;
        ss << "Window " << i;
        renderWindow->SetWindowName(ss.str().c_str());
        renderWindow->SetPosition(i*300,0);

        //create a sphere
        vtkSmartPointer<vtkSphereSource> sphereSource =
          vtkSmartPointer<vtkSphereSource>::New();
        sphereSource->SetCenter(0.0, 0.0, 0.0);
        sphereSource->SetRadius(5.0);
        sphereSource->Update();

        //Create a mapper and actor
        vtkSmartPointer<vtkPolyDataMapper> mapper =
          vtkSmartPointer<vtkPolyDataMapper>::New();
        mapper->SetInputConnection(sphereSource->GetOutputPort());

        vtkSmartPointer<vtkActor> actor =
          vtkSmartPointer<vtkActor>::New();
        actor->SetMapper(mapper);
        renderer->AddActor(actor);
        renderer->ResetCamera();
      }

      interactors[3]->Start();

      return EXIT_SUCCESS;
    }

### CMakeLists.txt

    cmake_minimum_required(VERSION 2.8)

    PROJECT(MultipleRenderWindows)

    find_package(VTK REQUIRED)
    include(${VTK_USE_FILE})

    add_executable(MultipleRenderWindows MACOSX_BUNDLE MultipleRenderWindows.cxx )

    target_link_libraries(MultipleRenderWindows ${VTK_LIBRARIES})

### Download and Build MultipleRenderWindows

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

    cd MultipleRenderWindows/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:

    ./MultipleRenderWindows

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