Open VTK-9.2.6 as child window inside existing c++ Windows application

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1

I am trying to create a vtkRenderWindow as child window in existing c++ Windows Application using the VTK-9.2.6 version. As base code I used an old example from VTK/Examples/GUI/Win32/SimpleCxx/Win32Cone.cxx as written in some old VTKUsersGuide https://vtk.org/wp-content/uploads/2021/08/VTKUsersGuide.pdf. It looks as in 9.2 version the folder GUI/Win32/ doesn’t exist and I can’t find what is wrong with my code.
vtkNew renderWindow;
vtkNew renderer;
renderWindow->SetWindowName(“Sphere”);
renderWindow->AddRenderer(renderer);
renderWindow->SetParentId(hWnd);

SetParentId doesn’t create a window inside the window application. Tried to use casting window to specific vtkWin32OpenGLRenderWindow as suggested in this answer: c++ - How to add a WIN32 VTK client window inside any existing app already having a main window parent? - Stack Overflow . still the window was not created.

My code example:

LRESULT CALLBACK WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static HWND ewin;
//static myVTKApp* theVTKApp;
static UINT width;
static UINT height; switch (message)
{
case WM_CREATE:
{
WNDCLASSEX wc = {};
wc.cbSize = sizeof(WNDCLASSEX);
wc.lpfnWndProc = WndProc;
wc.hInstance = GetModuleHandle(NULL);
wc.lpszClassName = “aa”;

    if (!RegisterClassEx(&wc))
        return NULL;

    ewin = CreateWindowEx(0,
        "button", "Exit",
        WS_CHILD | WS_VISIBLE | WS_CLIPSIBLINGS ,
        20, 400, 400, 60,
        hWnd, 
        (HMENU)2,
        GetModuleHandle(NULL),
        NULL);
    
    StartVtk(hWnd);
}
break;
case WM_COMMAND:
    {
        ...
    }
    break;
case WM_PAINT:
    {
        ...
    }
    break;
case WM_DESTROY:
    PostQuitMessage(0);
    break;
default:
    return DefWindowProc(hWnd, message, wParam, lParam);
}
return 0;

}

void StartVtk(HWND hWnd)
{
vtkNew colors;

// Create a sphere
vtkNew<vtkSphereSource> sphereSource;
sphereSource->SetCenter(0.0, 0.0, 0.0);
sphereSource->SetRadius(5.0);
sphereSource->SetPhiResolution(100);
sphereSource->SetThetaResolution(100);

vtkNew<vtkPolyDataMapper> mapper;
mapper->SetInputConnection(sphereSource->GetOutputPort());

vtkNew<vtkActor> actor;
actor->SetMapper(mapper);
actor->GetProperty()->SetColor(colors->GetColor3d("Cornsilk").GetData());

vtkNew<vtkRenderer> renderer;
vtkNew<vtkRenderWindow> renderWindow;
renderWindow->SetWindowName("Sphere");
renderWindow->AddRenderer(renderer);
renderWindow->SetParentId(hWnd);
vtkRenderWindow* rp = renderWindow.GetPointer();
vtkWin32OpenGLRenderWindow* rw = nullptr;

if (static_cast<vtkOpenGLRenderWindow*>(rp)) {
    rw = static_cast<vtkWin32OpenGLRenderWindow*>(rp);
    rw->SetParentId(hWnd);
}
else {
   
}

auto a = renderWindow->GetGenericParentId();
HWND pHandle = (HWND)(void*)rw->GetGenericParentId();

vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
renderWindowInteractor->SetRenderWindow(renderWindow);

renderer->AddActor(actor);
renderer->SetBackground(0, 0.4, 1);
renderWindow->SetSize(400, 400);
renderWindow->Render();

try
{
    renderWindowInteractor->Start(); 
}
catch (...)
{
}

}

renderWindowInteractor->Start();

  • From this line code never returns. Stuck at
    void vtkWin32RenderWindowInteractor::StartEventLoop();
    as the window wasn’t created and no messages are being received
    Even without adding interactor, the vtkRenderWindow doesn’t render itself.

Thanks for help,
Elena