# Innovative System for BIM/GIS Integration in the Context of Urban Sustainability
## 5 Discussion  
Using Autodesk Infrawworks still has some disadvantages, caused by the depth of the information and the limitations of the software itself. In fact, despite its advanced features, Infrawworks still fails to fully handle all characteristics of BIM and GIS data. Therefore, a valid alternative could be the use of a virtual/augmented/mixed reality app, which allows for immediate visualization of the issues related to city planning and the potential of interacting with the model both in situ and on site. The app provides flexibility and convenience when visualizing interventions directly on site, enabling stakeholders to immediately assess and interact with the 3D models in real time. This pragmatic viewpoint is essential for making well-informed decisions during the project's execution phase, enabling modifications and enhancements as necessary. However, combining a software module with Cesium libraries provides a more customizable and reliable solution that goes beyond simple visualization. It creates an all-inclusive, freely accessible system that can be tailored and expanded in accordance with the particular project necessities. Undoubtedly, the proposed experimental approach with Cesium ion represents a future direction in this field: the creation of a platform that integrates 3D-4D data within a three-dimensional geospatial environment. The advanced customization of the layers present in the library would make it possible to obtain increasingly detailed information at the building level, thus guaranteeing true integration of the potential of both software programs. The developers could therefore implement increasingly complex and complete scripts to be inserted within the Cesium open-source platform, viewable on any device.  
In the literature, many contributions highlight similar approaches. [PERSON] et al. (2024) [PERSON] et al. (2024) proposed data transformation methods involving mapping. They converted IFC data into CityGML and subsequently into PWL/RDF, visualizing the results on the Cesium ion platform. [PERSON] et al. (2024) proposed an interesting methodology for integrating open data related to solar radiation with in situ measurements to develop a GIS-based digital twin and create maps useful for urban planners and farmers. However, they highlight the necessity of combining mapped data with a database based on available energy and lighting. In the same field, [PERSON] and [PERSON] (2020) focused their research on calculating solar incident radiation using remote sensing data for the creation of an urban digital twin. Simultaneously, [PERSON] et al. (2020) used a module called \"Sandbox\" to create a platform with Unreal Engine for visualization in virtual/augmented reality. Overall, the issue of integrating BIM and GIS is well presented by [PERSON] et al., (2020) who discuss data conversion and emerging technologies like virtual and augmented reality. Referring to the contemporary literature cited above, this work proposes a solution for the correct georeferencing of buildings (IFC data) in Cesium ion in a GIS environment, an issue that is still complex. Moreover, the innovative aspect lies in its ability to provide information in the 4D domain (a real new characteristic in this field), and to present a case study demonstrating the use of the entire system for planning building renovation interventions and potentially realizing a digital twin starting from a point cloud. Obviously, all the potential problems relating to the loss of detailed information that occur during the conversion of files from a source format to a target format could remain, which are currently subject to further investigation.