cityjson / website

Source code for https://cityjson.org

CityJSON

This repository is where the specifications and the schemas of CityJSON are kept. All previous versions are kept in tags in the commits.

For all the details, see the official CityJSON website: https://cityjson.org.

What is CityJSON?

CityJSON is a JSON-based encoding for a subset of the OGC CityGML data model (version 3.0.0), which is an open standardised data model and exchange format (in GML) to store digital 3D models of cities and landscapes.

The aim of CityJSON is to offer an alternative to the GML encoding of CityGML, which can be verbose and complex (and thus rather frustrating to work with). CityJSON aims at being easy-to-use, both for reading datasets, and for creating them. It was designed with programmers in mind, so that tools and APIs supporting it can be quickly built, and several software have been created already.

Contributing to the project

We invite anyone to contribute to the development and improvement of CityJSON, all discussions, issues, and developments are open to everyone.

If you use CityJSON in an academic context, please cite this article

Ledoux H, Arroyo Ohori K, Kumar K, Dukai B, Labetski A, Vitalis S (2019). CityJSON: A compact and easy-to-use encoding of the CityGML data model. Open Geospatial Data, Software and Standards, 4:4 (DOI) (PDF)

website's Issues

Section 3 (Geometry) of specs should mention GeometryInstances

Currently, the Geometry section of the specification doesn't list GeometryInstances as one type of geometries. This is misleading as someone that doesn't read the whole document might be confused about what has to be done in order to support all possible geometry types.

I think just a simple warning in section 3 that references section 6 as an exception would solve the issue.

Link to a section of 'latest' specs

I would like to use permanent link to a specific section of latest version of the specs:

For example: https://www.cityjson.org/specs/latest/#transform-object

But this redirects me to the root: https://www.cityjson.org/specs/1.0.0

While using a specific version works as expected: https://www.cityjson.org/specs/1.0.0/#transform-object

Invalid texture data in twobuildings.city.json

I think texture data is invalid in the example twobuildings.city.json.
"geometry" has "texture" member, but "appearance" object is missed

Datasets with errors

I know we provide several datasets for download that were converted from CityGML datasets that had errors, therefore the CityJSON datasets have errors too. I know it's not our job to fix this but we should flag it. As a newbie I would be studying the datasets intensely and errors would confuse me a lot.

Faulty link in getting started guide

Tiny mistake here:
https://www.cityjson.org/help/users/getting-started/#visualise-it

The "list of viewers" link is wrong, should be
https://www.cityjson.org/software/#viewers