CityJSON

CityJSON is a data format designed for the effective encoding and exchange of 3D city models. It is based on the JSON (JavaScript Object Notation) format, making it human-readable and easy to process with standard web technologies. CityJSON aims to facilitate interoperability among diverse applications involved in urban planning, simulation, visualization, and geospatial analysis.

The format supports the representation of various city features such as buildings, roads, vegetation, water bodies, and other infrastructural elements. Its schema enables the encoding of geometric, thematic, and topological information in a structured manner, allowing for detailed 3D modeling that can include multiple levels of detail (LOD). CityJSON extends the CityGML standard but simplifies it by using JSON, which often results in more compact and easier-to-handle files.

Key features of CityJSON include the use of lightweight syntax, compact encoding, and the ability to embed metadata and semantic information. It also supports features like object grouping, appearance attributes, and consistency checks, which promote data quality and usability.

Since its inception, CityJSON has been adopted by various organizations and open-source communities aiming to enhance the accessibility and exchange of urban spatial data. Its design promotes easier data sharing and integration across different software tools and platforms, fostering collaboration in urban planning, disaster management, and environmental analysis.

Overall, CityJSON represents a streamlined, versatile format for 3D city model data, promoting open standards and interoperability within the geospatial and urban modeling communities.