text: // ----------------------------------------------------------------------------
  // -                        Open3D: www.open3d.org                            -
  // ----------------------------------------------------------------------------
  // The MIT License (MIT)
  //
  // Copyright (c) 2018 www.open3d.org
  //
  // Permission is hereby granted, free of charge, to any person obtaining a copy
  // of this software and associated documentation files (the "Software"), to deal
  // in the Software without restriction, including without limitation the rights
  // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  // copies of the Software, and to permit persons to whom the Software is
  // furnished to do so, subject to the following conditions:
  //
  // The above copyright notice and this permission notice shall be included in
  // all copies or substantial portions of the Software.
  //
  // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  // IN THE SOFTWARE.
  // ----------------------------------------------------------------------------
  
  #include "Open3D/Utility/IJsonConvertible.h"
  
  #include <json/json.h>
  
  namespace open3d {
  namespace utility {
  
  bool IJsonConvertible::EigenVector3dFromJsonArray(Eigen::Vector3d &vec,
                                                    const Json::Value &value) {
      if (value.size() != 3) {
          return false;
      } else {
          vec(0) = value[0].asDouble();
          vec(1) = value[1].asDouble();
          vec(2) = value[2].asDouble();
          return true;
      }
  }
  
  bool IJsonConvertible::EigenVector3dToJsonArray(const Eigen::Vector3d &vec,
                                                  Json::Value &value) {
      value.clear();
      value.append(vec(0));
      value.append(vec(1));
      value.append(vec(2));
      return true;
  }
  
  bool IJsonConvertible::EigenVector4dFromJsonArray(Eigen::Vector4d &vec,
                                                    const Json::Value &value) {
      if (value.size() != 4) {
          return false;
      } else {
          vec(0) = value[0].asDouble();
          vec(1) = value[1].asDouble();
          vec(2) = value[2].asDouble();
          vec(3) = value[3].asDouble();
          return true;
      }
  }
  
  bool IJsonConvertible::EigenVector4dToJsonArray(const Eigen::Vector4d &vec,
                                                  Json::Value &value) {
      value.clear();
      value.append(vec(0));
      value.append(vec(1));
      value.append(vec(2));
      value.append(vec(3));
      return true;
  }
  
  bool IJsonConvertible::EigenMatrix3dFromJsonArray(Eigen::Matrix3d &mat,
                                                    const Json::Value &value) {
      if (value.size() != 9) {
          return false;
      } else {
          for (int i = 0; i < 9; i++) {
              mat.coeffRef(i) = value[i].asDouble();
          }
          return true;
      }
  }
  
  bool IJsonConvertible::EigenMatrix3dToJsonArray(const Eigen::Matrix3d &mat,
                                                  Json::Value &value) {
      value.clear();
      for (int i = 0; i < 9; i++) {
          value.append(mat.coeffRef(i));
      }
      return true;
  }
  
  bool IJsonConvertible::EigenMatrix4dFromJsonArray(Eigen::Matrix4d &mat,
                                                    const Json::Value &value) {
      if (value.size() != 16) {
          return false;
      } else {
          for (int i = 0; i < 16; i++) {
              mat.coeffRef(i) = value[i].asDouble();
          }
          return true;
      }
  }
  
  bool IJsonConvertible::EigenMatrix4dToJsonArray(const Eigen::Matrix4d &mat,
                                                  Json::Value &value) {
      value.clear();
      for (int i = 0; i < 16; i++) {
          value.append(mat.coeffRef(i));
      }
      return true;
  }
  
  bool IJsonConvertible::EigenMatrix4dFromJsonArray(Eigen::Matrix4d_u &mat,
                                                    const Json::Value &value) {
      if (value.size() != 16) {
          return false;
      } else {
          for (int i = 0; i < 16; i++) {
              mat.coeffRef(i) = value[i].asDouble();
          }
          return true;
      }
  }
  
  bool IJsonConvertible::EigenMatrix4dToJsonArray(const Eigen::Matrix4d_u &mat,
                                                  Json::Value &value) {
      value.clear();
      for (int i = 0; i < 16; i++) {
          value.append(mat.coeffRef(i));
      }
      return true;
  }
  
  bool IJsonConvertible::EigenMatrix6dFromJsonArray(Eigen::Matrix6d &mat,
                                                    const Json::Value &value) {
      if (value.size() != 36) {
          return false;
      } else {
          for (int i = 0; i < 36; i++) {
              mat.coeffRef(i) = value[i].asDouble();
          }
          return true;
      }
  }
  
  bool IJsonConvertible::EigenMatrix6dToJsonArray(const Eigen::Matrix6d &mat,
                                                  Json::Value &value) {
      value.clear();
      for (int i = 0; i < 36; i++) {
          value.append(mat.coeffRef(i));
      }
      return true;
  }
  
  bool IJsonConvertible::EigenMatrix6dFromJsonArray(Eigen::Matrix6d_u &mat,
                                                    const Json::Value &value) {
      if (value.size() != 36) {
          return false;
      } else {
          for (int i = 0; i < 36; i++) {
              mat.coeffRef(i) = value[i].asDouble();
          }
          return true;
      }
  }
  
  bool IJsonConvertible::EigenMatrix6dToJsonArray(const Eigen::Matrix6d_u &mat,
                                                  Json::Value &value) {
      value.clear();
      for (int i = 0; i < 36; i++) {
          value.append(mat.coeffRef(i));
      }
      return true;
  }
  
  }  // namespace utility
  }  // namespace open3d
  