Sources and licences

Jetvolta recreates nine of its ten cities from open map data: Tokyo, New York, Istanbul, Frankfurt, Los Angeles, Rio de Janeiro, Mexico City, Sydney and Marrakesh. Harbor Bay is fictional and uses no third-party map data. This page lists the sources, their licences, what we changed, and where the derived database can be downloaded.

Naming a source does not mean that the source or its publisher supports or endorses Jetvolta.

1. OpenStreetMap (ODbL)

© OpenStreetMap contributors. The streets, building outlines, water, green areas, railways, district boundaries and other data of the cities come from OpenStreetMap and are available under the Open Database License (ODbL) 1.0. More: openstreetmap.org/copyright.

What we changed. For each city we cut an area a few kilometres wide out of the OSM data and simplified the geometry (outlines and lines in map metres, district zones simplified to 2 metres, building heights added from other sources). The data is stored in our own format designed for the game (gzip-compressed JSON), which is not the format OpenStreetMap uses.

Derived database for download. The files below are a derived database in the sense of the ODbL. We offer them here permanently and free of charge under the ODbL 1.0. Each checksum (SHA-256) belongs to the file of exactly the size shown. If you cannot find a file, write to kontakt@jetvolta.com.

Download address: https://jetvolta.com/quellen/daten/<file name> – every file is linked in the tables.

Main files (one per city):

Related files (heights, zones, ground zones, additions, corrections). They contain OSM identifiers or OSM values and are available under the same licence; they also contain data from the sources in sections 2 to 7, whose licences apply to that data:

2. Copernicus DEM (terrain heights Istanbul, Rio de Janeiro, Mexico City, Marrakesh)

The terrain heights of these four cities come from the Copernicus DEM GLO-30 (“Licence for the use of the Copernicus WorldDEM-30”, licence text). We resampled the heights to a 30-metre grid in map metres (adapted). As the licence requires:

produced using Copernicus WorldDEM-30 © DLR e.V. 2010-2014 and © Airbus Defence and Space GmbH 2014-2018 provided under COPERNICUS by the European Union and ESA; all rights reserved.

The organisations in charge of the Copernicus programme by law or by delegation do not incur any liability for any use of the Copernicus WorldDEM-30.

Airbus, the European Union, ESA and the Copernicus programme do not support or endorse our use.

3. NSW Spatial Services (terrain heights Sydney)

Terrain heights Sydney: NSW Foundation Spatial Data Framework – Elevation and Depth – Digital Elevation Model (5 m), licensed under CC BY 4.0, adapted. Attribution as requested by Spatial Services (spatial.nsw.gov.au/copyright):

© State of New South Wales (Spatial Services, a business unit of the Department of Customer Service NSW). For current information go to spatial.nsw.gov.au.

We averaged the 5-metre heights to a 30-metre grid in map metres and set the harbour water to 0 metres. Spatial Services does not endorse Jetvolta.

4. Hessian Administration for Land Management and Geoinformation (building heights Frankfurt)

Building heights Frankfurt: 3D-Gebäudemodell LoD2 Hessen © Hessische Verwaltung für Bodenmanagement und Geoinformation (HVBG), gds.hessen.de, adapted. Licence according to the metadata: Datenlizenz Deutschland – Namensnennung – Version 2.0; under § 18 of the Hessian surveying act (HVGG) any use is permitted without conditions, changes must be indicated. We matched the building heights to the OpenStreetMap outlines – the data has been changed.

5. Project PLATEAU / Tokyo 3D Digital Map (building heights Tokyo)

Building heights Tokyo: 東京都3Dデジタルマップ / Tokyo 3D Digital Map, Project PLATEAU (Tokyo Metropolitan Government, 2025), CC BY 4.0, adapted. Licence: Creative Commons Attribution 4.0 (terms of use of the Ministry of Land, Infrastructure, Transport and Tourism: mlit.go.jp/plateau/site-policy). We matched the building heights to the OpenStreetMap outlines and processed them with our own rules. Source statement in the form required by the PLATEAU terms of use:

出典：3D都市モデル（Project PLATEAU）東京都23区（2025年度）（国土交通省）（https://www.geospatial.jp/ckan/dataset/plateau）を加工して作成

(Source: 3D City Model (Project PLATEAU), Tokyo 23 wards, FY2025, Ministry of Land, Infrastructure, Transport and Tourism, processed by Jetvolta.) LOD2 parts (Takanawa, Toranomon): 国土交通省 / Ministry of Land, Infrastructure, Transport and Tourism (MLIT), 2023 – the Tokyo data contain LOD2 building models built by the MLIT in FY2023 for Takanawa (高輪周辺地区) and Toranomon; two towers in the game take their height from such roof surfaces. The copyright in the 3D city models belongs to the respective municipality. The ministry did not create the adapted data and does not support Jetvolta.

6. NYC Open Data (building heights New York)

Building heights New York: NYC Open Data, Building Footprints (NYC OTI), adapted (dataset 5zhs-2jue, as of 21 September 2026). We converted the heights from feet to metres and matched them to the OpenStreetMap buildings. The City of New York does not guarantee the accuracy or completeness of this data; the data has been modified for this game. The City’s notice for applications using its data, verbatim:

The City of New York can not vouch for the accuracy or completeness of data provided by this web site or application or for the usefulness or integrity of the web site or application. This site provides applications using data that has been modified for use from its original source, NYC.gov, the official web site of the City of New York.

7. Further sources

• Los Angeles: Building height corrections: County of Los Angeles, LARIAC6 Buildings 2020 (Countywide Building Outlines), adapted. Terrain heights: U.S. Geological Survey, 3D Elevation Program (3DEP), Bare-Earth-DEM (The National Map), adapted.
• Rio de Janeiro: Building heights: Instituto Pereira Passos, Prefeitura da Cidade do Rio de Janeiro, Edificações (2013), CC BY 4.0, adapted.
• Mexico City: Building heights: Google Open Buildings 2.5D Temporal (Google Research; Sirko et al. 2023, arXiv:2310.11622), CC BY 4.0, adapted. Tower heights: Wikidata (CC0).
• Marrakesh: Building heights (zones): European Commission, Joint Research Centre, GHS-BUILT-H R2023A (Pesaresi & Politis 2023), © European Union 2023, doi:10.2905/85005901-3A49-48DD-9D19-6261354F56FE, CC BY 4.0, adapted.
• Fonts: Open Sans SemiBold (© 2020 The Open Sans Project Authors, designed by Steve Matteson, part of the Godot Engine), Noto Sans Arabic (© 2022 The Noto Project Authors), Noto Sans CJK (© 2014–2021 Adobe) and Exo 2 (Copyright 2013 The Exo 2 Project Authors, designed by Natanael Gama; title font of the menus), all under the SIL Open Font License 1.1; Noto Sans Arabic, Noto Sans CJK and Exo 2 as subsets with the characters the game uses (assets/fonts/LIZENZEN.md).

8. Music

Music and jingles come from free sources. Only “Deadly Contracts” requires attribution:

“Deadly Contracts” from “Retro Synthwave Loops” © Tomasz Kucza (Magnesus), licensed under CC BY 4.0. Converted to Ogg Vorbis, otherwise unchanged.

All files were retrieved on 13 September 2026; the pieces are not cut, only converted to Ogg Vorbis (quality 5, 44.1 kHz).

9. Game engine

Jetvolta is made with Godot Engine 4.7.2 and uses Jolt Physics, both under the MIT license. Godot Engine © 2014-present Godot Engine contributors, © 2007-2014 Juan Linietsky, Ariel Manzur. Jolt Physics © 2021 Jorrit Rouwe. Sources: godotengine.org/license, github.com/jrouwe/JoltPhysics.

Godot includes components from other projects, each under its own licence. Their full copyright notices and licence texts, as the engine itself lists them: licences of the engine components. Among them: Portions of this software are copyright © 2025 The FreeType Project (https://freetype.org). All rights reserved.

MIT License

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

10. The source lines per city

The credits in the game (menu “Contributors”, section “Map data”) read as follows for each city. The line “© OpenStreetMap contributors (ODbL)” applies to each of the nine cities; Harbor Bay has no third-party data. The lines are shown in the wording used in the game. (The Copernicus line is shortened here; the full wording is in section 2.)

Listed once for all cities as well: “Abgeleitete Datenbank zum Download (ODbL): jetvolta.com/quellen.html”, the two Copernicus sentences from section 2 (in English, verbatim) and “CC BY 4.0: creativecommons.org/licenses/by/4.0”.

11. Contact

Questions about sources, licences and the downloads: kontakt@jetvolta.com.