gig-line/Docs/odbl-review.md

ODbL review — OpenStreetMap-derived data in the shipped build

Status: decision recorded 2026-11-08 (closes the TODO "Review ODbL obligations" item).

1. What OSM data the project touches

Use	Where it lives	In the shipped build?
Raw OSM extract (Hollywood block, 2026-11-06)	Geo/raw/osm-api-map-2026-11-06.osm (+2 building ways .json), committed	No — dev data only, not packed
Blosm blockout geometry (streets, building footprints, sidewalks)	Crates/site meshes derived from the extract, imported to Unreal	Yes — the walkable block geometry derives from OSM layout
USGS 3DEP DEM elevation	Geo/raw/dem-3dep-1m-26911-2026-11-06.tif	Yes — but public domain (US Government work), independent of ODbL

So the shipped build contains buildings, streets and sidewalks whose footprints come from OSM data (layout geometry). That geometry is a derivative database/knowledge extract under the ODbL framing.

2. ODbL obligations (Open Database Licence 1.0)

ODbL = Open Database Licence (Open Data Commons, version 1.0). The OSM community contract uses it for the OpenStreetMap database.

Key obligations when you redistribute or produce a derivative database:

1. Attribution — credit the database, with a notice visible to users, and provide a link to the licence.
2. Share-alike — a derivative database (including a "Produced Work" from it) must be offered under ODbL, and changes must be made available.
3. Keep the data open — do not add technical or legal restrictions that prevent others from using the database under ODbL.
4. No database right / extraction limits — substantial extraction/use must follow the licence's "extraction and reuse" terms.

Important nuance: ODbL governs the database (the OSM data as a collection and the knowledge it encodes). Separate creative content — art, code, models authored by the project — is not a "database" and does not carry the share-alike obligation. The game's own code and artist-authored geometry are project-owned (CC0 per LICENSE).

3. Where the project stands

Obligation	Held by	Evidence
Attribution in the game	Yes — on-screen credit every frame	AGigLineHUD draws "© OpenStreetMap contributors" and "Data © OpenStreetMap contributors, ODbL 1.0 — openstreetmap.org/copyright" bottom-left (GigLineHUD.h lines 29/33)
Attribution in the repo	Yes — provenance + licence recorded	THIRD_PARTY_NOTICES.md Geographic data table; Geo/manifests/2026-11-06-osm-api-map.md
Licence text available	Yes — link + notice	HUD link to openstreetmap.org/copyright (ODbL); THIRD_PARTY_NOTICES points at ODbL 1.0
Source data available (share-alike enabler)	Yes — the exact extract is committed, with bbox/date/hash	Geo/raw/osm-api-map-2026-11-06.osm + manifest
Derivative database offered under ODbL	Recorded as a decision — see §4	This document

4. Decision: posture for the derived geometry

The OSM-derived block geometry (streets, footprints, sidewalks) is treated as a Produced Work / derivative database of the OpenStreetMap database.

• The share-alike obligation is accepted for the data layer only. The release must carry: (a) the on-screen attribution (implemented), (b) the ODbL link (implemented), and (c) an offer of the OSM source for the geometry — satisfied by the committed raw extract plus its manifest.
• Project creative work (code, shaders, artist-authored façades, textures) is NOT under ODbL. It remains project-owned CC0 (see LICENSE) and carries no share-alike obligation. Only geometry that can be argued to encode OSM database facts (streets, building footprints, sidewalk layouts) is in scope.
• No new obligation is created by the DEM: 3DEP is US Government public domain and is independent of ODbL.
• Do not import OSM imagery/panoramas as textures (OSM map tiles or aerial imagery are separately licensed); the project already treats OSM as layout only (Docs/licensing.md rule 3).

Release checklist items this lands:

• In-game attribution shown (HUD).
• ODbL notice + link (HUD + THIRD_PARTY_NOTICES).
• Source OSM data committed with provenance (manifest: date, bbox, SHA-256).
• Posture recorded here for the release gate.

5. Remaining (tracked separately)

• Blosm add-on licence is still pending in THIRD_PARTY_NOTICES (tool-only, not distributed — must be checked once, not a release blocker for ODbL).
• Façade signage/trademarks: separate rights from the photograph, own the geometry; not an ODbL question (see THIRD_PARTY_NOTICES "Reference photography" rules).

6. Sources checked

• ODbL text: https://opendatacommons.org/licenses/odbl/1-0/
• OSM licence summary: https://www.openstreetmap.org/copyright
• ISPRS/ODbL practice notes on derived game geometry from OSM footprints (objective standard: attribution + produced-work offer, share-alike limited to the data layer).

Not reviewed here (out of scope for this item): engine redistribution terms (Epic), MPFB asset terms, street-prop reuse terms — all tracked in THIRD_PARTY_NOTICES.md.