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私はレンダリングした3D .vtkモデルを持っており、結果はvtkContourFilter（Ubuntu 16.04でvtkバージョン7.0.0を使用）を使用して輪郭を抽出します。vtk C++ contourfilterから輪郭を更新
私は異なる視点から投影したいと思いますが、カメラの位置が変わったことを確認しました（私はカメラ位置が実際に変更されていることを確認しました）。各反復で起動するインタラクティブビューアは常に最初の画像。
見つかった輪郭点（私はvtkPolyDataとして保存されています）の最初の数個の座標を出力すると、私の輪郭点セットの内容は変わらないことにも気付きました。
ContFilter->Modified();
ContFilter->Update();
と
polyData->Modified(); // This is the 3D vtkPolyData that I project
と
ContFilter->SetValue(0, 10);
ContFilter->SetValue(0, 255);
を私も追加しようとした野生の推測通り：
は、私はそのような追加などの他人のために働いていたいくつかのオンラインの提案を、試してみました：
ContourFilterを使用する前に、forループ内のが、更新されません。それで、私は、私が考えることができ、オンラインで見つけることができるすべてを試みました。
これは、関連するコードです：
// Prepare the rendering environment to project the 3D model to an image from different perspectives
vtkSmartPointer<vtkDataSetMapper> mapper = vtkSmartPointer<vtkDataSetMapper>::New();
mapper->SetInputData(polyData);
mapper->ScalarVisibilityOff();
vtkSmartPointer<vtkActor> actor = vtkSmartPointer<vtkActor>::New();
actor->SetMapper(mapper);
actor->GetProperty()->SetInterpolationToFlat();
vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
renderer->SetBackground(1,1,1);
renderer->AddActor(actor);
vtkSmartPointer<vtkCamera> camera = vtkSmartPointer<vtkCamera>::New();
vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New();
renderWindow->SetOffScreenRendering(1);
vtkSmartPointer<vtkWindowToImageFilter> windowToImageFilter = vtkSmartPointer<vtkWindowToImageFilter>::New();
vtkSmartPointer<vtkContourFilter> ContFilter = vtkSmartPointer<vtkContourFilter>::New();
vtkSmartPointer<vtkPolyData> contour = vtkSmartPointer<vtkPolyData>::New();
// Loop over the camera positions. At each iteration render/project,
// extract the contour and finally render the 3D model and the found
// contour
double * iPoint;
double * camPos;
double * contourStart;
int nContours;
for(int i=0; i<positions->GetNumberOfPoints(); i++){
// Print the camera position
iPoint = positions->GetPoint(i);
std::cout << iPoint[0] << " " << iPoint[1] << " " << iPoint[2] << std::endl;
//Move camera
camera->SetPosition(iPoint[0], iPoint[1], iPoint[2]);
camera->SetFocalPoint(focalPointOrig[0], focalPointOrig[1], focalPointOrig[2]);
camera->SetViewAngle(viewAngle);
camera->Modified();
camera->SetRoll(90);
// Does this help to update the view?
polyData->Modified();
// Remove old links and set them again
renderWindow->RemoveRenderer(renderer);
mapper->RemoveAllInputs();
renderer->SetActiveCamera(camera);
renderWindow->AddRenderer(renderer);
renderer->Modified();
renderer->ResetCameraClippingRange();
renderWindow->Modified();
// Render/project the data
mapper->SetInputData(polyData);
renderWindow->Render();
// Print camera position for debugging
camera->GetPosition(camPos);
std::cout << camPos[0] << " " << camPos[1] << " " << camPos[2] << std::endl;
// Get the image and apply a contourfilter
windowToImageFilter->SetInput(renderWindow);
windowToImageFilter->Update();
ContFilter->SetInputConnection(windowToImageFilter->GetOutputPort());
// Saw someone do this as a workaround for updating the view
ContFilter->SetValue(0, 10);
ContFilter->SetValue(0, 255);
// Does this help to update the view?
ContFilter->Modified();
//Get the contour from the contourfilter
ContFilter->Update();
contour = ContFilter->GetOutput();
// Print the first points coordinates to see if they changed
contourStart = contour->GetPoint(1);
std::cout << contourStart[0] << " " << contourStart[1] << " " << std::endl;
// Print the number of contours to see if it may be stored as an additional contour
nContours = ContFilter->GetNumberOfContours();
std::cout << nContours << std::endl;
// Render the 3D model and the found contour
actor->GetProperty()->SetColor(0.9,0.9,0.8);
// Create a mapper and actor of the silhouette
vtkSmartPointer<vtkPolyDataMapper> mapper_contour = vtkSmartPointer<vtkPolyDataMapper>::New();
mapper_contour->SetInputData(contour);
// Try this again here
polyData->Modified();
vtkSmartPointer<vtkActor> actor_contour = vtkSmartPointer<vtkActor>::New();
actor_contour->SetMapper(mapper_contour);
actor_contour->GetProperty()->SetLineWidth(2.);
// 2 renderers and a render window
vtkSmartPointer<vtkRenderer> renderer1 = vtkSmartPointer<vtkRenderer>::New();
renderer1->AddActor(actor);
vtkSmartPointer<vtkRenderer> renderer2 = vtkSmartPointer<vtkRenderer>::New();
renderer2->AddActor(actor_contour);
// Set the 3D model renderer to the same perspective but don't change the camera perspective of the contour
renderer1->SetActiveCamera(camera);
// Setup the window
vtkSmartPointer<vtkRenderWindow> renderwindow = vtkSmartPointer<vtkRenderWindow>::New();
renderwindow->SetSize(1600, 800);
renderwindow->AddRenderer(renderer1);
renderer1->SetViewport(0., 0., 0.5, 1.);
renderwindow->AddRenderer(renderer2);
renderer2->SetViewport(0.5, 0., 1., 1.);
// Setup the interactor
vtkSmartPointer<vtkInteractorStyleTrackballCamera> style = vtkSmartPointer<vtkInteractorStyleTrackballCamera>::New();
vtkSmartPointer<vtkRenderWindowInteractor> iren = vtkSmartPointer<vtkRenderWindowInteractor>::New();
iren->SetRenderWindow(renderwindow);
iren->SetInteractorStyle(style);
// Display the coordinate system axes
vtkSmartPointer<vtkAxesActor> axes = vtkSmartPointer<vtkAxesActor>::New();
vtkSmartPointer<vtkOrientationMarkerWidget> widget = vtkSmartPointer<vtkOrientationMarkerWidget>::New();
widget->SetOutlineColor(0.9300, 0.5700, 0.1300);
widget->SetOrientationMarker(axes);
widget->SetInteractor(iren);
widget->SetViewport(0.0, 0.0, 0.4, 0.4);
widget->SetEnabled(1);
widget->InteractiveOn();
// Render the 3D model and the found contour
renderwindow->Render();
iren->Start();
}