c++ - 程序在短暂渲染后立即自动停止

Question

我在使用 VTK 时遇到了一个小问题。当我启动我的程序时，它开始渲染然后自动停止，而实际上它应该继续渲染。我看不出那个错误可能来自哪里。我为完全相同的渲染编写了另一段代码，效果很好。

所以这是我的类的构造函数:

Drawing::Drawing(void)
{
    translation = vtkSmartPointer<vtkTransform>::New();
    ctxView = vtkContextView::New();
    win = ctxView->GetRenderWindow();
    ren = ctxView->GetRenderer();
    cam = ren->GetActiveCamera();

    ren->SetBackground(.0,.0,.0);
}

这是一段不起作用的代码:

void Drawing::read(){

    std::string filename = BUNNY;
    // Read all the data from the file
    vtkSmartPointer<vtkXMLPolyDataReader> reader =vtkSmartPointer<vtkXMLPolyDataReader>::New();
    reader->SetFileName(filename.c_str());
    reader->Update();

    cout << "File Found and Loaded : " << filename << endl ;

    vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
    mapper->SetInputConnection(reader->GetOutputPort());

    mainActor = vtkSmartPointer<vtkActor>::New();
    mainActor->SetMapper(mapper);

    ren->AddActor(mainActor);

    win->PolygonSmoothingOn();
    win->Render();
    win->Start();
}

下面是一段有效的代码:

void otherRead(){
    std::string filename = BUNNY;
    // Read all the data from the file
    vtkSmartPointer<vtkXMLPolyDataReader> reader =vtkSmartPointer<vtkXMLPolyDataReader>::New();
    reader->SetFileName(filename.c_str());
    reader->Update();

    cout << "File Found and Loaded : " << filename << endl ;

    // Visualize
    vtkSmartPointer<vtkPolyDataMapper> mapper = vtkSmartPointer<vtkPolyDataMapper>::New();
    mapper->SetInputConnection(reader->GetOutputPort());

    mainActor = vtkSmartPointer<vtkActor>::New();
    mainActor->SetMapper(mapper);

    vtkSmartPointer<vtkRenderer> renderer = vtkSmartPointer<vtkRenderer>::New();
    vtkSmartPointer<vtkRenderWindow> renderWindow = vtkSmartPointer<vtkRenderWindow>::New();
    renderWindow->AddRenderer(renderer);
    vtkSmartPointer<vtkRenderWindowInteractor> renderWindowInteractor = vtkSmartPointer<vtkRenderWindowInteractor>::New();
    renderWindowInteractor->SetRenderWindow(renderWindow);

    vtkRenderWindowInteractor *iren = vtkRenderWindowInteractor::New();
    iren->SetRenderWindow(renderWindow);

    vtkInteractorStyleMultiTouchCamera *style =
    vtkInteractorStyleMultiTouchCamera::New();
    iren->SetInteractorStyle(style);

    renderer->AddActor(mainActor);
    renderer->SetBackground(0,0,0); // Background color green

    renderWindow->PolygonSmoothingOn();
    renderWindow->Render();
    renderWindowInteractor->Start();
}

我不知道这实际上是 vtk 还是 c++ 的问题。不工作的代码段的输出只是几毫秒的窗口，然后程序存在，而 otherRead() 在不退出程序的情况下提供正常呈现。

在此先感谢您的帮助

Answer 1

所以确实是vtk的问题。有些人可能会说一个非常基本的东西，但当您开始使用 vtk 时仍然不是那么容易理解。我发布了答案，关于 vtk 的文档并不多，所以它可能会帮助其他新手。所以实际上，必须启动窗口的事件循环。这可以通过以下几行来完成:

vtkRenderWindowInteractor *iren = vtkRenderWindowInteractor::New();
iren->SetRenderWindow(win);
vtkInteractorStyleMultiTouchCamera *style =
vtkInteractorStyleMultiTouchCamera::New();
iren->SetInteractorStyle(style);

//Start the event loop
iren->Initialize();
iren->Start();

希望这有帮助:)