Hello,
I’m using vtkContourWidget to select cells on a surface/polydata and I would like to initialize the contour.
I have no issues if I use only vtkcontourwidget and vtkPolygonalSurfacePointPlacer. I have created a polydata containing points that fit on my initial surafce, and initialize the contourwidget with it (contourWidget->Initialize(polydata)).
But when adding vtkPolygonalSurfaceContourLineInterpolator I got a bug. The message indicates an nullptr error on nodeBegin and nodeEnd (into the vtkPolygonalSurfaceContourLineInterpolator class).
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int numPts = 4;
vtkSmartPointer points = vtkSmartPointer::New();
points->InsertPoint(static_cast(0), -36.604606, 3.172031, -15.775561);
points->InsertPoint(static_cast(1), 29.504172, 2.542050, -21.521465);
points->InsertPoint(static_cast(2), 13.557625, 5.584614, 17.892294);
points->InsertPoint(static_cast(3), -17.859298, 8.136532, 17.122012);
vtkIdType* vertexIndices = new vtkIdType[numPts + 1];
for (int i = 0; i < numPts; i++) { vertexIndices[i] = static_cast<vtkIdType>(i); }
vertexIndices[numPts] = 0;
vtkSmartPointer<vtkCellArray> lines = vtkSmartPointer<vtkCellArray>::New();
lines->InsertNextCell(numPts + 1, vertexIndices);
vtkSmartPointer<vtkPolyData> polydataPickedPoints = vtkSmartPointer<vtkPolyData>::New();
polydataPickedPoints->SetPoints(points);
polydataPickedPoints->SetLines(lines);
polydataPickedPoints->Modified();
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vtkSmartPointer<vtkContourWidget> contourWidget = vtkSmartPointer<vtkContourWidget>::New();
contourWidget->SetInteractor(interactor);
contourWidget->On();
vtkSmartPointer<vtkOrientedGlyphContourRepresentation> rep = vtkOrientedGlyphContourRepresentation::SafeDownCast(contourWidget->GetRepresentation());
rep->GetLinesProperty()->SetColor(1, 0.2, 0);
rep->GetLinesProperty()->SetLineWidth(3.0);
vtkSmartPointer<vtkPolygonalSurfacePointPlacer> pointPlacer = vtkSmartPointer<vtkPolygonalSurfacePointPlacer>::New();
pointPlacer->AddProp(actor);
pointPlacer->GetPolys()->AddItem(pd);
rep->SetPointPlacer(pointPlacer);
vtkSmartPointer<vtkPolygonalSurfaceContourLineInterpolator> interpolator = vtkSmartPointer<vtkPolygonalSurfaceContourLineInterpolator>::New();
interpolator->GetPolys()->AddItem(pd);
rep->SetLineInterpolator(interpolator);
contourWidget->Initialize(polydataPickedPoints);
Could you help me understand how to initialize the contourwidget in case of using it with vtkPolygonalSurfaceContourLineInterpolator ? Or how to add nodes on the contour (similar issues than Contour filter - add nodes programatically ) ?
Thanks by advance for helping me
arnaud