Isochrone

Third-party notices

This project redistributes the third-party assets and data listed below. Each entry states what is redistributed, under which licence, and what the licence requires us to carry.

Material Symbols (icon font)

• What: web/fonts/material-symbols-subset.woff2 — the transport-mode icons in the Options panel (directions_walk, directions_bike, directions_car, directions_boat, directions_bus) and the menu glyph on the Options button itself.
• Copyright: © Google LLC
• Licence: Apache License 2.0 — full text in web/fonts/LICENSE-Apache-2.0.txt
• Source: https://github.com/google/material-design-icons / https://fonts.google.com/icons
• Modifications: The upstream font has been subset to only the six glyphs listed above (obtained via the Google Fonts CSS API’s icon_names subsetting, reducing ~4 MB to ~2 KB). No glyph outlines were altered. This note satisfies the Apache-2.0 §4(b) requirement to state that the files were changed.

The font is self-hosted rather than loaded from Google’s CDN, so viewing the app sends no request to Google.

Because the file holds only those six glyphs, adding an icon to the UI means regenerating the subset first - otherwise the new ligature renders as its own literal text (menu, directions_train, …). Ask the CSS API for the full list, then download the src URL it returns:

curl -A "Mozilla/5.0" "https://fonts.googleapis.com/css2?family=Material+Symbols+Outlined&icon_names=directions_bike,directions_boat,directions_bus,directions_car,directions_walk,menu"

Update the glyph list above, and the count in the @font-face comment in web/src/styles.css, to match.

OpenStreetMap data

• What: the routing graph and the district/coastline/forest/water/airport basemap layers, built by data_pipeline/ into data_pipeline/output/.
• Copyright: © OpenStreetMap contributors
• Licence: Open Database License (ODbL) — https://www.openstreetmap.org/copyright

Attribution is shown in the app footer and embedded in every exported SVG.

Public transit data (per region)

GTFS stop and connection tables, folded into the routing graph of the region they belong to. Each feed is licensed on condition of attribution, so each is credited separately.

Berlin

• Copyright: © VBB (Verkehrsverbund Berlin-Brandenburg)
• Licence: Creative Commons Attribution 4.0 (CC BY 4.0) — http://www.vbb.de/vbbgtfs
• Note: fetched via the vbb-gtfs.jannisr.de mirror because VBB’s own gtfs.zip has a reproducibly corrupted stop_times.txt entry. VBB remains the licence holder to credit; the mirror is a technical detail.

Adelaide

• Copyright: © Adelaide Metro — Department for Infrastructure and Transport, South Australia
• Licence: Creative Commons Attribution 4.0 (CC BY 4.0) — https://data.sa.gov.au/data/dataset/https-gtfs-adelaidemetro-com-au
• Note: licence confirmed 2026-08-17 against the publisher’s own CKAN API (license_id=cc-by). The feed covers South Australia state-wide; the build clips it to the region extent.

Attribution is shown in the app footer, and in exported SVGs and printed output, whenever a region with transit data is loaded. The operator, licence name and link travel with the region in the locations manifest rather than being hardcoded, so adding a feed cannot ship uncredited data — a pipeline test fails if a configured feed has no attribution block.