[vtkusers] Overlay slice on vtkResliceImageViewer and change slice when scrolling

[ochampao]

Hello,

Below I have attached a minimal code example of what I describe in my
initial post, i.e. overlay a slice but not being able to change it when
scrolling through the dicom volume.

===============================================
int main(int argc, char** argv)
{
    vtkNew<vtkDICOMImageReader> reader;
    vtkNew<vtkResliceImageViewer> resliceImageViewer;
    vtkNew<vtkRenderWindowInteractor> renderWindowInteractor;
    vtkNew<vtkInteractorStyleImage> style;
    vtkNew<vtkRenderWindow> renderWindow;
    vtkNew<vtkRenderer> renderer;
    vtkSmartPointer<vtkImageData> dcmImage;

    renderWindow->AddRenderer(renderer);
    renderer->SetBackground(0.0, 0.0, 0.0);
    renderWindowInteractor->SetInteractorStyle(style);

    //load dicom
    reader->SetDirectoryName("<path_to_dicom_series>");
    reader->Update();
    dcmImage = reader->GetOutput();

    resliceImageViewer->SetInputData(dcmImage);
    resliceImageViewer->SetRenderWindow(renderWindow);
    resliceImageViewer->SetupInteractor(renderWindowInteractor);
    resliceImageViewer->SetResliceModeToAxisAligned();
    resliceImageViewer->SetSlice(50);
    resliceImageViewer->SetColorLevel(-27);
    resliceImageViewer->SetColorWindow(1358);

    // Create mask volume
    vtkSmartPointer<vtkImageData> maskImage =
vtkSmartPointer<vtkImageData>::New();
    int extent[6];

    dcmImage->GetExtent(extent);
    int xDim = extent[1] - extent[0] + 1;
    int yDim = extent[3] - extent[2] + 1;
    int zDim = extent[5] - extent[4] + 1;

    maskImage->SetSpacing(dcmImage->GetSpacing());
    maskImage->SetDimensions(xDim, yDim, zDim);
    maskImage->AllocateScalars(VTK_DOUBLE, 1);

    double scalarvalue = 0.0;

    // colour mask
    for (int y = extent[2]; y < extent[3]; y++) {
        for (int x = extent[0]; x < extent[1]; x++) {
            for (int z = extent[4]; z < extent[5]; z++) {
                double* pixel =
static_cast<double*>(maskImage->GetScalarPointer(x, y, z));

                pixel[0] = scalarvalue;
                scalarvalue += 1.0;
            }
            scalarvalue = 0.0;
        }
        scalarvalue = 0.0;
    }

	// create lookup table
    vtkSmartPointer<vtkLookupTable> lookupTable =
vtkSmartPointer<vtkLookupTable>::New();
    lookupTable->SetNumberOfTableValues(zDim);
    lookupTable->SetRange(0, zDim-1);
    lookupTable->Build();
    
	// get slice axes and set pass-through point 
    vtkSmartPointer<vtkMatrix4x4> resliceAxes =
vtkSmartPointer<vtkMatrix4x4>::New();
   
resliceAxes->DeepCopy(resliceImageViewer->GetResliceCursorWidget()->GetResliceCursorRepresentation()->GetResliceAxes()->GetData());
    resliceAxes->SetElement(0, 3, 0);
    resliceAxes->SetElement(1, 3, 0);
    resliceAxes->SetElement(2, 3, 100);

	// extract slice
    vtkSmartPointer<vtkImageReslice> reslice =
vtkSmartPointer<vtkImageReslice>::New();
    reslice->SetInputData(maskImage);
    reslice->SetOutputDimensionality(2);
    reslice->SetResliceAxes(resliceAxes);
    reslice->SetInterpolationModeToLinear(); 
    reslice->SetOutputSpacing(maskImage->GetSpacing());

	// map colours
    vtkSmartPointer<vtkImageMapToColors> mapTransparency2 =
vtkSmartPointer<vtkImageMapToColors>::New();
    mapTransparency2->SetLookupTable(lookupTable);
    mapTransparency2->PassAlphaToOutputOn();
    mapTransparency2->SetInputConnection(reslice->GetOutputPort());

	// setup image actor for slice
    vtkSmartPointer<vtkImageActor> maskActor =
vtkSmartPointer<vtkImageActor>::New();
   
maskActor->GetMapper()->SetInputConnection(mapTransparency2->GetOutputPort());

    double pos[3];
    maskActor->GetPosition(pos);
    pos[2] = 55;
    maskActor->SetPosition(pos);
    maskActor->SetOpacity(0.5);
    
    resliceImageViewer->GetRenderer()->AddActor(maskActor);
    resliceImageViewer->GetRenderer()->ResetCamera(); 

    renderWindowInteractor->Start();

    return 0;

}
===============================================




--
Sent from: http://vtk.1045678.n5.nabble.com/VTK-Users-f1224199.html