# Kongsgård / Stavanger map sources

Map data © OpenStreetMap contributors, available under the [Open Database License (ODbL) 1.0](https://opendatacommons.org/licenses/odbl/1-0/). The derived local-coordinate map dataset is also provided under ODbL 1.0. Display attribution linking to [OpenStreetMap copyright](https://www.openstreetmap.org/copyright) wherever this map is shown.

The saved Overpass responses were obtained from `https://overpass-api.de/api/interpreter` on 12 September 2026. The primary response records OSM base timestamp `2026-09-12T22:16:49Z`.

- `stavanger-osm-source.json`: buildings, building parts, highway ways, natural/land-use/park features, schools, mapped trees and amenity nodes.
- `stavanger-overpass-query.txt`: the exact primary query.
- `stavanger-osm-relations.json`: full multipolygon members and geometry, including Breiavatnet, Byparken, Torget and Domkirkeplassen. Query: `[out:json][timeout:35];relation[type=multipolygon](58.9660,5.7264,58.9720,5.7380);out body geom;`
- `stavanger-osm-furniture-rail.json`: streetlamp points, station point and railway lines. Query: `[out:json][timeout:20];(node[highway=street_lamp](58.9660,5.7264,58.9720,5.7380);node[railway=station](58.9660,5.7264,58.9720,5.7380);way[railway](58.9660,5.7264,58.9720,5.7380););out tags geom;`

The derived [local-coordinate dataset is downloadable here](stavanger-map.json) under ODbL 1.0. The game imports the same dataset from `src/stavanger-map.json` through `src/stavanger-data.js`. Original OSM IDs and tags are retained. Latitude/longitude coordinates are transformed from WGS84 ECEF into the local tangent plane at latitude 58.969, longitude 5.732: x points east, z points south, units are metres. Projected coordinates are stored to 0.0001 metre; that storage precision does not imply survey-grade source accuracy.

Way vertices are not simplified. Multipolygon member ways are stitched by shared endpoints; inner rings remain holes. Features with multiple outer rings are split while retaining their original OSM relation ID. Roads and building footprints crossing the requested map boundary remain complete. The Vågen water polygon follows the three mapped coastline ways and is closed at the northern map boundary solely to define the rendered extent.

Ground-floor building collision should normally exclude features marked `isUnderground` or `isOpenCanopy`. `buildingParts` is separate to prevent duplicate base-footprint collision. Mapped road widths appear only when tagged; untagged widths are null. Footways and roads retain access/tunnel/covered tags. Building height tags are retained where available; untagged heights, facades and inferred road widths are visual reconstructions. Elevation comes from the separate measured Kartverket terrain dataset described below.

School functional labels were cross-referenced to Rogaland fylkeskommune’s 2023 *Stavanger katedralskole — Areal- og funksjonsanalyse*, section 3.1, and the [school’s official premises description](https://www.stavanger-katedralskole.vgs.no/hovedmeny/skolen-var/om-skolen/skolens-lokaler/). Original OSM names remain separate from display labels. Gameplay markers are existing mapped pedestrian-way vertices with clear space around them; they identify nearby destinations and are not claims about official entrances.

## Measured terrain and reconstructed architecture

Terrain is from Kartverket DTM1, sampled at 5m spacing. See [terrain-README.md](terrain-README.md) for CC BY 4.0 attribution, the vertical datum, original API responses, water levels, and explicit interpolation limits. School and cathedral facade details use official exterior photographs as references; the game does not distribute those photographs. Building heights without source tags, facade details, stair dimensions, and street furnishings remain visual reconstructions.

## Street-level detail pass, September 2026

- [Street stairs](street-stairs-README.md): above-ground OSM stair centerlines now have solid treads and landings, with handrails where tagged. Torgtrappene uses its entire mapped plaza polygon and its mapped 20 steps. One-metre DTM1 profiles, estimated widths/counts, and unresolved source conflicts are documented separately.
- Courtyard and building details use the [official Kongsgård panorama tour](https://stavkat.no/kongsgaard/) (courtyard photography dated 2 March 2021), municipal cathedral restoration photos from 2024, and the school's exterior photographs. Photographs are references, not textures shipped in the game.
- Atlantic Hotel and Romsøegården have distinct reconstructed facade grids, entrances, glazing and source-readable signs. Their exact facade measurements and upper-volume divisions are not surveyed. The townhall uses the municipality's refurbishment-design images, with its opening planned for autumn 2026; these are not a completed-building survey.
- Zebra crossings appear only on OSM paths explicitly tagged as zebra crossings. Tactile guidance lines follow paths tagged tactile_line=yes. Stripe dimensions and tactile rib spacing are visual estimates.
- Photographic surface scans are downloaded locally from [Poly Haven](https://polyhaven.com/). See [texture licenses and source records](/textures/polyhaven/LICENSE.md). These CC0 scans represent suitable material types, not scans of these particular Stavanger buildings.

The result preserves mapped horizontal layout and measured terrain, while many facade, furnishing and stair measurements remain reconstructed. A current, complete exterior survey or licensed textured 3D scan would be needed to call the area an exact digital replica.