# Integration of BIM and GIS for the Digitization of the Built Environment
## 3 Methodology
### Closed-Source Methodology  
CSE is a type of software whose use is permitted only under certain conditions specified in the license, restricting activities such as study, modification, sharing, distribution or analysis. These restrictions are imposed by the holder of the economic rights, which may be the author himself or the assignee of the rights, through legal means such as clauses in the license agreement or restrictions on sources or patents in countries where this is permitted. Restrictions may also include technical elements, such as distributing software only in binary code without making the source code available. This practice makes it impossible to study and modify the software, which would require advanced computer skills and considerable effort to obtain information. The Free Software Foundation (FSF) employs the term \"proprietary software\" to designate software that is not free or only partially free. However, technically, the term encompasses any software that is controlled by a single entity, so it could be applied to any software that is not in the public domain [71]. Proprietary software is developed with the intention of offering a service against payment, whereas free software is developed with the objective of guaranteeing the freedom customization of software from users, without any kind of limits. The AECO sector is represented in the market by a number of large companies that are leading providers of BIM and GIS software, such as Autodesk, Graphisoft, ESRI and ACCA [72; 73; 74; 75]. [PERSON] et al. [76] propose an innovative process for transforming a motorway model based on a GIS into a well-structured BIM platform using the visual programming tool Dynamo. The developed process involves the conversion of poly-curves from the GIS model into BIM-compatible model curves, the classification of attributes into shape families, and the integration of traffic data from traffic detection and recording stations. The finalized multi-dimensional BIM platform, which extends from three to eight dimensions, incorporates essential project details and traffic data. To guarantee interoperability, an Open BIM process is employed, which involves the generation of an IFC file, enabling efficient data exchange between different software and stakeholders. The CS methodology is illustrated as follows (Figure 7), with the relevant tools and software used during the development process. The initial development phase of the CS methodology can be outlined as follows. Firstly, the GIS software environment is established, in this case ESRI's ArcGIS Pro 3.4 [77]. Esri (the Environmental System Research Institute) is one of the leading producers of GIS software systems and applications for the management of geospatial databases. ArcGIS is a geographic information system that is employed for the creation, analysis, and technical use of maps, the compilation of geographic data, and the sharing and management of geographic information within a database. This phase encompasses the definition of the standardized coordinate system to be employed, the selection of the graphical display mode of the model and the background map, and, finally, the specification of the nomenclature for the Common Data Environment (CDE) repository to be followed and the final destination of the project file [78]. The selection of the coordinate system to be used as the basis for georeferencing is a crucial step in ensuring the interoperability of the systems (Figure 8). A terrestrial coordinate system is defined by a set of parameters that enable the unique identification of objects on the Earth's surface. The WGS84 (World Geodetic System 1984, also known as EPSG:4326) has been employed as the coordinate system. This is a geodetic, worldwide, ellipsoid-based geographic coordinate system that was developed in 1984 [79]. It represents the Earth from a geometrical and gravitational perspective, and was constructed on the foundation of measurements and scientific and technological knowledge available in 1984.