Method Initialize

Rendering/UI/vtkXRenderWindowInteractor.cxx:372–433

------------------------------------------------------------------------------ Initializes the event handlers without an XtAppContext. This is good for when you don't have a user interface, but you still want to have mouse interaction.

// good for when you don't have a user interface, but you still
// want to have mouse interaction.
void vtkXRenderWindowInteractor::Initialize()
{
  if (this->Initialized)
  {
    return;
  }

  vtkRenderWindow* ren;
  int* size;

  // make sure we have a RenderWindow and camera
  if (!this->RenderWindow)
  {
    vtkErrorMacro(<< "No renderer defined!");
    return;
  }

  this->Initialized = 1;
  ren = this->RenderWindow;

  ren->EnsureDisplay();
  this->DisplayId = static_cast<Display*>(ren->GetGenericDisplayId());

  vtkXRenderWindowInteractorInternals::Instances.insert(this);

  size = ren->GetActualSize();
  size[0] = ((size[0] > 0) ? size[0] : 300);
  size[1] = ((size[1] > 0) ? size[1] : 300);
  if (this->DisplayId)
  {
    this->Internal->DisplayConnection = ConnectionNumber(this->DisplayId);
    vtkXSync(this->DisplayId, False);
  }

  ren->Start();
  ren->End();

  this->WindowId = reinterpret_cast<Window>(ren->GetGenericWindowId());

  if (this->DisplayId && this->WindowId)
  {
    XWindowAttributes attribs;
    //  Find the current window size
    auto* previousHandler = vtkXSetErrorHandler([](Display*, XErrorEvent*) { return 0; });
    if (vtkXGetWindowAttributes(this->DisplayId, this->WindowId, &attribs))
    {
      size[0] = attribs.width;
      size[1] = attribs.height;
    }
    else
    {
      // window does not exist. `ren` is not an X11 render window.
      this->WindowId = 0;
    }
    vtkXSetErrorHandler(previousHandler);
  }
  ren->SetSize(size[0], size[1]);