c++ - 可视化工具包-如何读取和渲染多个对象？

我正在尝试使用vtk读取和呈现目录中的多个文件(当它们组合在一起形成一个对象时)。但是到目前为止，我收到以下错误:

ERROR: In D:\VTK\VTK-src\IO\XML\vtkXMLReader.cxx, line 283
vtkXMLPolyDataReader (00D1B560): Error opening file D:\3d models\Dist\.

ERROR: In D:\VTK\VTK-src\Common\ExecutionModel\vtkExecutive.cxx, line 782
vtkCompositeDataPipeline (00CC2078): Algorithm
vtkXMLPolyDataReader(00D1B560) returned failure for request: vtkInformation
(00D20688)
  Debug: Off
  Modified Time: 8721
  Reference Count: 1
  Registered Events: (none)
  Request: REQUEST_DATA
  FORWARD_DIRECTION: 0
  ALGORITHM_AFTER_FORWARD: 1
  FROM_OUTPUT_PORT: 0

到目前为止，我尝试的是仅读取1个文件而不是多个文件，但是我仍然遇到上面提到的错误。

这是我正在处理的编码:

int main(int argc, char *argv[])
{
  std::string directoryName = "D:\\3d models\\Dist\\" ;

  vtkSmartPointer<vtkDirectory> directory = vtkSmartPointer<vtkDirectory>::New();
  int opened = directory->Open(directoryName.c_str());

  if(!opened)
  {
    std::cout << "No es posible abrir este directorio!" << std::endl;
    return EXIT_FAILURE;
  }

  int numberOfFiles = directory->GetNumberOfFiles();
  std::cout << "NUmero de archivos: " << numberOfFiles << std::endl;

  for (int i = 0; i < numberOfFiles; i++)
  {
    std::string fileString = directoryName;
    ////fileString += "/";
    fileString += directory->GetFile(i);

    std::string ext = vtksys::SystemTools::GetFilenameLastExtension(fileString);
    std::cout << fileString.c_str() << " extension: " << ext << std::endl;

    std::string name = vtksys::SystemTools::GetFilenameWithoutLastExtension(fileString);
    std::cout << "nombre: " << name << std::endl;

    const char*cstr = fileString.c_str();
    std::cout << cstr << endl;

        vtkSmartPointer<vtkXMLPolyDataReader> reader =
            vtkSmartPointer<vtkXMLPolyDataReader>::New();
        reader->SetFileName(cstr);
        reader->Update();
        reader->GetOutput();

        vtkSmartPointer<vtkTransform> transform =
            vtkSmartPointer<vtkTransform>::New();
        transform->Scale(.005, .005, .005);

        vtkSmartPointer<vtkTransformFilter> transformFilter =
            vtkSmartPointer<vtkTransformFilter>::New();
        transformFilter->SetInputConnection(reader->GetOutputPort());
        transformFilter->SetTransform(transform);

        // Visualizar
        vtkSmartPointer<vtkPolyDataMapper> mapper =
            vtkSmartPointer<vtkPolyDataMapper>::New();
        mapper->SetInputConnection(transformFilter->GetOutputPort());

        vtkSmartPointer<vtkActor> actor =
            vtkSmartPointer<vtkActor>::New();
        actor->SetPosition(1.1, .5, .1);
        actor->SetMapper(mapper);

        vtkSmartPointer<vtkOpenVRRenderer> renderer =
            vtkSmartPointer<vtkOpenVRRenderer>::New();
        vtkSmartPointer<vtkOpenVRRenderWindow> renderWindow =
            vtkSmartPointer<vtkOpenVRRenderWindow>::New();
        renderWindow->AddRenderer(renderer);
        vtkSmartPointer<vtkOpenVRRenderWindowInteractor> renderWindowInteractor =
            vtkSmartPointer<vtkOpenVRRenderWindowInteractor>::New();
        renderWindowInteractor->SetRenderWindow(renderWindow);

        vtkNew<vtkOpenVRCamera> cam;
        renderer->SetActiveCamera(cam);

        renderer->AddActor(actor);
        renderer->SetBackground(.2, .3, .4);

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

  }

  return EXIT_SUCCESS;
}

我想念什么？我尝试使用不同类型的文件，但仍无法使用此方法读取和呈现任何内容。

最佳答案

当您列出文件夹中的文件时，它看起来像第一个条目是“。”。 (这是正常的)，因此您尝试打开的文件的路径为“D:\ 3d模型\ Dist \”。它不是vtkXMLPolyDataReader的有效文件。

您只应尝试打开用vtkXMLPolyDataWriter编写的vtk文件。
例如，通过检查扩展名为“.vtp”(或用于保存包含vtkPolyData模型的文件的任何扩展名)。

在循环的第一部分中检查扩展名:

for (int i = 0; i < numberOfFiles; i++)
  {
    std::string fileString = directoryName;
    ////fileString += "/";
    fileString += directory->GetFile(i);

    std::string ext = vtksys::SystemTools::GetFilenameLastExtension(fileString);
    std::cout << fileString.c_str() << " extension: " << ext << std::endl;

    // add this line here to skip "." and "..", also fix the extension if not .xml
    if (ext.find(".vtp") == std::string::npos) continue;

    (...)

我还怀疑您在尝试使用vtkXMLPolyDataReader时尝试使用vtkXMLPolyDataReader(这实际上取决于用来生成文件的编写器)。 vtkXMLPolyDataReader是.vtp文件的标准阅读器。

最后，您要在循环内部创建一个渲染器，一个渲染窗口和一个摄像头:这意味着每个对象一个窗口。这很罕见，是您想要的吗？

长话短说:您至少需要一个渲染器和一个窗口来显示一个或多个模型。您的模型分别由一个actor表示:窗口是渲染器绘制(一个或多个)actor的地方。渲染器是一个渲染过程:当然，每个 Actor 可以有一个渲染过程，但是除非您确定需要，否则就不需要。

这是您的代码，就像我在您的位置所做的那样进行了修改:

int main(int argc, char *argv[])
{
    std::string directoryName = "D:\\3d models\\Dist\\" ;

    vtkSmartPointer<vtkOpenVRRenderer> renderer =
        vtkSmartPointer<vtkOpenVRRenderer>::New();
    vtkSmartPointer<vtkOpenVRRenderWindow> renderWindow =
            vtkSmartPointer<vtkOpenVRRenderWindow>::New();
    renderWindow->AddRenderer(renderer);
    vtkSmartPointer<vtkOpenVRRenderWindowInteractor> renderWindowInteractor =
            vtkSmartPointer<vtkOpenVRRenderWindowInteractor>::New();
    renderWindowInteractor->SetRenderWindow(renderWindow);
    vtkNew<vtkOpenVRCamera> cam;
    renderer->SetActiveCamera(cam);
    renderer->SetBackground(.2, .3, .4);

    vtkSmartPointer<vtkDirectory> directory = vtkSmartPointer<vtkDirectory>::New();
    int opened = directory->Open(directoryName.c_str());

    if(!opened)
    {
        std::cout << "No es posible abrir este directorio!" << std::endl;
        return EXIT_FAILURE;
    }

    int numberOfFiles = directory->GetNumberOfFiles();
    std::cout << "NUmero de archivos: " << numberOfFiles << std::endl;

    for (int i = 0; i < numberOfFiles; i++)
    {
        std::string fileString = directoryName;
        ////fileString += "/";
        fileString += directory->GetFile(i);

        std::string ext = vtksys::SystemTools::GetFilenameLastExtension(fileString);
        std::cout << fileString.c_str() << " extension: " << ext << std::endl;

        if (ext.find(".vtp") == std::string::npos) continue;

        std::string name = vtksys::SystemTools::GetFilenameWithoutLastExtension(fileString);
        std::cout << "nombre: " << name << std::endl;

        const char*cstr = fileString.c_str();
        std::cout << cstr << endl;

        vtkSmartPointer<vtkXMLPolyDataReader> reader =
                vtkSmartPointer<vtkXMLPolyDataReader>::New();
        reader->SetFileName(cstr);
        reader->Update();
        reader->GetOutput();

        vtkSmartPointer<vtkTransform> transform =
                vtkSmartPointer<vtkTransform>::New();
        transform->Scale(.005, .005, .005);

        vtkSmartPointer<vtkTransformFilter> transformFilter =
                vtkSmartPointer<vtkTransformFilter>::New();
        transformFilter->SetInputConnection(reader->GetOutputPort());
        transformFilter->SetTransform(transform);

        // Visualizar
        vtkSmartPointer<vtkPolyDataMapper> mapper =
                vtkSmartPointer<vtkPolyDataMapper>::New();
        mapper->SetInputConnection(transformFilter->GetOutputPort());

        vtkSmartPointer<vtkActor> actor =
                vtkSmartPointer<vtkActor>::New();
        actor->SetPosition(1.1, .5, .1);
        actor->SetMapper(mapper);

        renderer->AddActor(actor);
    }

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

    return EXIT_SUCCESS;
}

关于c++ - 可视化工具包-如何读取和渲染多个对象？，我们在Stack Overflow上找到一个类似的问题：https://stackoverflow.com/questions/55364293/