[Tokyo Digital Twin Project」 https://info.tokyo-digitaltwin.metro.tokyo.lg.jp/
Created and released a Japanese version manual of the CityGML to CityJSON converter at Tokyo Metropolitan Government
https://github.com/tokyo-digitaltwin/citygml-tools
■ CityGML is widely used internationally as the data format for 3D city models, but there is also CityJSON, which is JSON-based, easy for developers to use, and smaller file size of about only 1/6 of CityGML.
■ As one of the activities of the "Tokyo Digital Twin Project," the Tokyo Metropolitan Government has created a Japanese version manual of the English version converter (citygml-tools) from CityGML to CityJSON and released it on GitHub "tokyo-digitaltwin" to promote the utilization of 3D city models and to make CityJSON widely used in the Japanese developer community.
[citygml-tools] https://github.com/citygml4j/citygml-tools
■ In addition to how to use the converter, the Japanese version manual also organizes know-how on how to convert Japanese data and how to deal with common errors that occur during conversion.