[Insight-users] Problem in obtaining world position with vtkSeedWidget

[Xiaopeng Yang]

I am trying to visualize a series of 2D DICOM images. After I change the vtkPointHandleRepresentation from 2D to 3D, no matter whether I move to another slice of image and select one seed point, the z value did not change.

The following is my code in main part:

  imageViewer21->SetInput(reader->GetOutput()); 
  this->ui->qvtkWidget->SetRenderWindow(imageViewer21->GetRenderWindow());
  imageViewer21->SetupInteractor(iren);
  imageViewer21->SetColorLevel(127);
  imageViewer21->SetColorWindow(255);
 
  vtkSliderRepresentation2D *SliderRepres = vtkSliderRepresentation2D::New();
  int min = imageViewer21->GetSliceMin();
  int max = imageViewer21->GetSliceMax();
  SliderRepres->SetMinimumValue(min);
  SliderRepres->SetMaximumValue(max);
  SliderRepres->SetValue(static_cast<int>((min + max) / 2));
  
  SliderRepres->GetPoint1Coordinate()->SetCoordinateSystemToNormalizedDisplay();
  SliderRepres->GetPoint1Coordinate()->SetValue(0.95, 0.9);
  SliderRepres->GetPoint2Coordinate()->SetCoordinateSystemToNormalizedDisplay();
  SliderRepres->GetPoint2Coordinate()->SetValue(0.95, 0.1);
  SliderRepres->SetSliderLength(0.02);
  SliderRepres->SetSliderWidth(0.03);
  SliderRepres->SetEndCapLength(0.01);
  SliderRepres->SetEndCapWidth(0.03);
  SliderRepres->SetTubeWidth(0.005);
  SliderRepres->SetLabelFormat("%3.0lf");
  SliderRepres->SetTitleHeight(0.05);
  SliderRepres->SetLabelHeight(0.055);

  vtkSliderWidget *SliderWidget = vtkSliderWidget::New();
  SliderWidget->SetInteractor(iren);
  SliderWidget->SetRepresentation(SliderRepres);
  SliderWidget->KeyPressActivationOff();
  SliderWidget->SetAnimationModeToAnimate();
  SliderWidget->SetEnabled(true);
  
  vtkSliderCallback2 *SliderCb = vtkSliderCallback2::New();
  SliderCb->SetImageViewer(imageViewer21);
  SliderWidget->AddObserver(vtkCommand::InteractionEvent, SliderCb);  

  imageViewer21->SetSlice(static_cast<int>(SliderRepres->GetValue()));
  imageViewer21->SetSliceOrientationToXY();

  // Create the representation
  vtkSmartPointer<vtkPointHandleRepresentation3D> handle = 
    vtkSmartPointer<vtkPointHandleRepresentation3D>::New();
  handle->GetProperty()->SetColor(0,0,0);
  handle->GetProperty()->SetOpacity(0);
  vtkSmartPointer<vtkSeedRepresentation> rep = 
    vtkSmartPointer<vtkSeedRepresentation>::New();
  rep->SetHandleRepresentation(handle);
 
  // Seed widget
  vtkSmartPointer<vtkSeedWidget> seedWidget = 
    vtkSmartPointer<vtkSeedWidget>::New();
  seedWidget->SetInteractor(iren);
  seedWidget->SetRepresentation(rep);
 
  vtkSmartPointer<vtkSeedCallback> seedCallback = 
  vtkSmartPointer<vtkSeedCallback>::New();
  seedCallback->SetRepresentation(rep);
  seedWidget->AddObserver(vtkCommand::PlacePointEvent,seedCallback);
  seedWidget->AddObserver(vtkCommand::InteractionEvent,seedCallback);
  seedWidget->On();

  imageViewer21->Render(); 
  imageViewer21->GetRenderer()->ResetCamera();

-----邮件原件-----
发件人: Karthik Krishnan [mailto:karthik.krishnan at kitware.com] 
发送时间: 2011년 1월 12일 수요일 오후 3:04
收件人: Xiaopeng Yang
抄送: vtk; insight-users at itk.org
主题: Re: [Insight-users] Problem in obtaining world position with vtkSeedWidget

The default representation for the individual handles created by
vtkSeedRepresentation is a 2D rep (vtkPointHandleRepresentation2D). It
does not have a notion of Z coordinate since its rendered on the
overlay plane. If you want 3D seeds, change the default handle
representation to an instance of  vtkPointHandleRepresentation3Dvia :
vtkSeedRepresentation::SetHandleRepresentation

On 1/11/11, Xiaopeng Yang <yxp233 at postech.ac.kr> wrote:
> Dear Users,
>
>
>
> I am trying to get world position by
> SeedRepresentation->GetSeedWorldPosition(I, pos). But comparing with other
> software, I got the wrong value in z coordinate. The values of x and y
> coordinates are correct. I would appreciate if anyone can point me in the
> right direction.
>
>
>
> Thanks,
>
> Yang
>
>
>
> class vtkSeedCallback : public vtkCommand
>
> {
>
>   public:
>
>     static vtkSeedCallback *New()
>
>     {
>
>       return new vtkSeedCallback;
>
>     }
>
>     vtkSeedCallback() {}
>
>     virtual void Execute(vtkObject*, unsigned long event, void *calldata)
>
>     {
>
>       if(event == vtkCommand::PlacePointEvent)
>
>       {
>
>         std::cout << "Point placed, total of: "
>
>             << this->SeedRepresentation->GetNumberOfSeeds() << std::endl;
>
>       }
>
>       if(event == vtkCommand::InteractionEvent)
>
>       {
>
>         if(calldata)
>
>         {
>
>           std::cout << "Interacting with seed : "
>
>               << *(static_cast< int * >(calldata)) << std::endl;
>
>         }
>
>       }
>
>
>
>       std::cout << "List of seeds (Display coordinates):" << std::endl;
>
>
>
>       for(vtkIdType i = 0; i < this->SeedRepresentation->GetNumberOfSeeds();
> i++)
>
>         {
>
>         double pos[3];
>
>         this->SeedRepresentation->GetSeedWorldPosition(i, pos);
>
>         std::cout << "(" << pos[0] << " " << pos[1] << " " << pos[2] << ")"
> << std::endl;
>
>         }
>
>
>
>      }
>
>
>
>     void SetRepresentation(vtkSmartPointer<vtkSeedRepresentation> rep)
> {this->SeedRepresentation = rep;}
>
>     private:
>
>     vtkSmartPointer<vtkSeedRepresentation> SeedRepresentation;
>
> };
>
>