This is the Unity Project that is used to develop and test https://github.com/ElmarJ/GeoJsonCityBuilder . The project contains a scene with a basic model of Amsterdam using the builtin renderer
Note that geojsoncitybuilder is here installed as a git submodule as a local Unity package.
To clone this repo:
git clone --recurse-submodules -j8 https://github.com/ElmarJ/geojsoncitybuilder.devenv.git
Enjoy!