Method LoadScene

Modules/SceneSerialization/src/mitkSceneJsonReader.cpp:436–1003

mitk::SceneJsonReader::~SceneJsonReader() = default;

bool mitk::SceneJsonReader::LoadScene(const std::string &sceneSourcePath, DataStorage *storage, bool clearStorageFirst)
{
  if (storage == nullptr)
  {
    mitkThrow() << "SceneJsonReader::LoadScene called with null DataStorage.";
  }

  // ---- 1. read and parse -------------------------------------------------

  std::ifstream in(sceneSourcePath);
  if (!in.good())
  {
    mitkThrow() << "Could not open scene file '" << sceneSourcePath << "' for reading.";
  }

  json document;
  try
  {
    in >> document;
  }
  catch (const json::exception &e)
  {
    mitkThrow() << "Scene file '" << sceneSourcePath << "' is not valid JSON: " << e.what();
  }

  // ---- 2. validate root --------------------------------------------------

  if (!document.is_object())
  {
    mitkThrow() << "Scene file '" << sceneSourcePath << "' root must be a JSON object.";
  }

  const auto typeIt = document.find(FIELD_TYPE);
  if (typeIt == document.end() || !typeIt->is_string() || typeIt->get<std::string>() != SCENE_TYPE)
  {
    mitkThrow() << "Scene file '" << sceneSourcePath << "' has missing or wrong 'type' field (expected '"
                << SCENE_TYPE << "').";
  }

  const auto versionIt = document.find(FIELD_VERSION);
  if (versionIt == document.end() || !versionIt->is_number_integer())
  {
    mitkThrow() << "Scene file '" << sceneSourcePath << "' has missing or non-integer 'version' field.";
  }
  const int version = versionIt->get<int>();
  if (version != SUPPORTED_VERSION)
  {
    mitkThrow() << "Scene file '" << sceneSourcePath << "' has unsupported version " << version
                << " (supported: " << SUPPORTED_VERSION << ").";
  }

  WarnUnknownKeys(document, ROOT_KNOWN_KEYS, "root");

  const auto metadataIt = document.find(FIELD_METADATA);
  if (metadataIt != document.end() && metadataIt->is_object())
  {
    WarnUnknownKeys(*metadataIt, METADATA_KNOWN_KEYS, "metadata");
  }