VTK: Enable split screen in the render window

Question

I am new to ITK/VTK and in learning process, in VTK how do we call multiple Visualization output windows at a time (splitter screen with different functionality for different output window). i tried implementing the above using multiple threads but i am not able to achieve the above desired..

// output window function 1
std::string inputFilename="E:\\DICOM_work\\CE53E85F";
vtkSmartPointer<vtkDICOMImageReader> reader =vtkSmartPointer<vtkDICOMImageReader>::New();
reader->SetFileName(inputFilename.c_str());
reader->Update();

// Visualize
vtkSmartPointer<vtkImageViewer2> imageViewer = vtkSmartPointer<vtkImageViewer2>::New();
imageViewer->SetInputConnection(reader->GetOutputPort());
vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor =  vtkSmartPointer<vtkRenderWindowInteractor>::New();
imageViewer->SetupInteractor(renderWindowInteractor);
imageViewer->Render();
imageViewer->GetRenderer()->ResetCamera();
imageViewer->Render();
renderWindowInteractor->Start();
} 
  // output window function 2 
void display1(void *)
{
std::string inputFilename="E:\\DICOM_work\\CE53E85Fg2";
vtkSmartPointer<vtkDICOMImageReader> reader1 = vtkSmartPointer<vtkDICOMImageReader>::New();
 reader1->SetFileName(inputFilename.c_str());
 reader1->Update();

// Visualize
vtkSmartPointer<vtkImageViewer2> imageViewer2 = vtkSmartPointer<vtkImageViewer2>::New();
imageViewer2->SetInputConnection(reader1->GetOutputPort());
 vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor1 = vtkSmartPointer<vtkRenderWindowInteractor>::New();
imageViewer2->SetupInteractor(renderWindowInteractor1);
imageViewer2->Render();
imageViewer2->GetRenderer()->ResetCamera();
imageViewer2->Render();
renderWindowInteractor1->Start();
 }

when ever i try to execute it.. the code executes till...
renderWindowInteractor->Start();

then the code exits with out executing the other function. Kindly help!

Answer 1

In the VTK official wiki, there is an example of an application that opens multiple vtkRenderWindows. Did you have a look at it? Basically, that program creates a vector of vtkRenderWindowInteractor:

std::vector<vtkSmartPointer<vtkRenderWindowInteractor> > interactors;

and, at the end, it calls the Start() method on the last element of it:

interactors[3]->Start();

('3' because it opens 4 windows). Maybe you can adapt that logic to the application of yours...

Just as a final note, consider that - if you like - you can also have a single vtkRenderWindow with multiple viewports.