Method WriteToStream

IO/Export/vtkGLTFExporter.cxx:543–683

}

void vtkGLTFExporter::WriteToStream(ostream& output)
{
  nlohmann::json cameras;
  nlohmann::json bufferViews;
  nlohmann::json buffers;
  nlohmann::json accessors;
  nlohmann::json nodes;
  nlohmann::json meshes;
  nlohmann::json textures;
  nlohmann::json images;
  nlohmann::json samplers;
  nlohmann::json materials;

  std::vector<size_t> topNodes;

  // support sharing texture maps
  std::map<vtkUnsignedCharArray*, size_t> textureMap;

  for (auto ren : vtk::Range(this->RenderWindow->GetRenderers()))
  {
    if (this->ActiveRenderer && ren != this->ActiveRenderer)
    {
      // If ActiveRenderer is specified then ignore all other renderers
      continue;
    }
    if (!ren->GetDraw())
    {
      continue;
    }

    // setup the camera data in case we need to use it later
    // the glTF "nodes" list stores global transformations for objects in the
    // scene, so we need to invert the ModelViewTransformMatrix of the camera
    // (by a copy, to avoid mutating the renderer's camera)
    nlohmann::json anode;
    anode["camera"] = cameras.size(); // camera node
    vtkMatrix4x4* mat = ren->GetActiveCamera()->GetModelViewTransformMatrix();
    vtkNew<vtkMatrix4x4> inv;
    inv->DeepCopy(mat);
    inv->Invert();
    for (int i = 0; i < 4; ++i)
    {
      for (int j = 0; j < 4; ++j)
      {
        anode["matrix"].emplace_back(inv->GetElement(j, i));
      }
    }
    anode["name"] = "Camera Node";

    // setup renderer group node
    nlohmann::json rendererNode;
    rendererNode["name"] = "Renderer Node";

    vtkPropCollection* pc;
    vtkProp* aProp;
    pc = ren->GetViewProps();
    vtkCollectionSimpleIterator pit;
    bool foundVisibleProp = false;