0016 – Places of a datadisk lie where history puts them

Status:

Accepted by the project owner and implemented in the working trees (not yet released)

Date:

2026-10-13

Context

A place could be put only near another, at a distance within a range and in a random direction, and inside the radius of its parent. The Cedar Forest of the Epic of Gilgamesh was 1 to 5 km from Uruk, and a temple of Uruk stood wherever the generator found room. The planet is as large as the Earth, so a story that happens in real places can put them where they were: the cedars grew in the mountains of Lebanon, 950 km from Uruk.

Decision

  • A place may carry locate: from (another place), bearing_deg (0 up the map, north, 90 east), distance_m and tolerance_m (default a twentieth of the distance, at least 30 m). The site is on the great circle distance_m from from in that direction; the bearing is read in the frame of the map of ``from``, the frame of its landscape patch and buildings, because the orientation of a generated planet is arbitrary and the map of a place must agree with the geography around it. See datadisk.schema.json.

  • The planet is not the Earth, so its coasts, mountains and seas lie elsewhere. The server takes the nearest site that satisfies the requires of the place: it tries points that spread out from the historical one, within tolerance_m first, then within four times and sixteen times as much, and logs how far from the historical point the place had to go. Placement fails, as before, only when there is no fit at all. locate cannot be combined with at.

  • A located place may still have a parent (so that it does not push its siblings away).

Consequences

  • Gilgamesh: Uruk is the place that the generator finds; the Cedar Forest lies 953 km to the west-north-west (292°), Mount Mashu 68 km south-east of it, Babylon 177 km north-west (320°), the head of the Gulf 333 km south-east and Dilmun 756 km south-east (139°). Inside Uruk the Eanna precinct and the Anu ziggurat stand where the excavations put them (217 m at 43° and 244 m at 34° from the middle of the site), the White Temple on the ziggurat, and new players appear just inside the Ishtar Gate (1254 m at 178°).

  • Journeys of the story are as long as they were: 950 km to the Cedar Forest is some 65 hours of walking. Faster travel (ships, portals, caravans) is a separate decision.

  • A different planet may put a place further from its historical point. Disks should therefore keep the requires of a located place loose.