tera/README.md

Tera

The map view of Lumbridge Simulate — cities from above, in three.js. Its other half, Spaces, is the offices you walk into: one engine and one asset library, seen from outside and from inside.

Apache 2.0. Runs at tera.lumbridgecorp.com.

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What it is

An engine plus data packs. The engine renders terrain, coastline, a built city on real street grids, bridges, roads, markers and air traffic. A city pack is pure data — coastlines, hills, districts, landmarks, camera chapters — so adding a city is a data contribution anyone can review, not a fork.

San Francisco ships today. Los Angeles / Orange County / Riverside is next; New York after that.

A plan view sits top right: the board drawn flat, with the footprint of the camera's own frustum on it, so you can see where you are looking from outside the shot. Click or drag it to move the camera; scroll it to dolly. It is a 2D canvas rather than a second WebGL context, drawn from the same city pack, and it follows the sun into the night along with everything else.

Who sees what

Three tiers, resolved once at boot by src/access.ts:

	anonymous	signed in	admin
the map, the plan view, the named chapters	✅	✅	✅
observed weather and live aircraft	✅	✅	✅
the office	public depth — shell, furniture, viewpoints, nobody home	full depth, with presence	full depth
the marker feed	per TERA_MARKERS_ACCESS	✅	✅
the godmode panel (G) — date, season, weather override, counters, pose editor	—	—	✅

The sky is public on purpose. Cloud cover over San Francisco is a government sensor reading, and the aircraft are broadcasting their positions unencrypted to anyone with a receiver; neither is something an account can grant you access to. Gating them cost the only moment that makes this project land — real fog rolling off the Pacific onto a city you recognise, at the real time of day, on a first visit.

The markers are the one feed that can carry something private, so the server decides. TERA_MARKERS_ACCESS is members by default and an operator has to say public out loud, which /api/v1/health then announces in degraded[]. The default is the safe answer rather than the common one, because the failure mode is silent: nothing errors, nothing looks broken, the data is just readable by the internet.

These are drawing decisions, not a security boundary, and src/access.ts says so at length. Live data and office presence are withheld by the API, from a caller it does not recognise; the client tier stops the app asking for something it will not get. Admin is granted only by TERA_ADMIN_SUBJECTS on the server — never inferred in the browser, and never from an API that failed to answer. A deployment with no API at all is open, because "clone it and it works" is the promise; it is not "clone it and you are an administrator".

Quick start

npm install
npm run dev

Using the engine

import { createScene } from "@lumbridge/tera/engine/scene.ts";
import { createStage } from "@lumbridge/tera/engine/stage.ts";
import SAN_FRANCISCO from "@lumbridge/tera/cities/sf.ts";

// One stage per canvas, for the life of the page. Cities are put on it and
// taken off again; a renderer per city leaks its shadow map on every switch.
const stage = createStage(canvas);

const scene = await createScene(stage, {
  city: SAN_FRANCISCO,
  markerPalette: { hiring: 0x4ade80, closed: 0xef4444 },
});

scene?.setMarkers([
  { id: "1", lat: 37.7765, lng: -122.4241, label: "Somewhere", colorKey: "hiring" },
]);

createScene is async because the heightfield is built in a Worker — half a million samples, about 730 ms on the Bay Area, and not on the main thread. It resolves to null if the build was abandoned through options.signal, which is what makes switching city mid-build cheap.

The engine renders Marker[] and looks colours up by colorKey in a palette you supply. It does not know what your markers mean — that mapping lives in your adapter. This is what lets one renderer serve a private map coloured by one scheme and a public map coloured by another, without either being a fork.

Adding a city

Write src/cities/<id>.ts exporting a City. Trace the coastline and parks by hand, place hills as radial peaks, and give each district its street bearing.

Two rules, and they are not stylistic:

• Do not import geometry from OpenStreetMap. OSM and Nominatim output is ODbL — share-alike, and incompatible with this repo's licence.
• Do not commit logos or brand assets. They are trademarks, not code.

See ARCHITECTURE.md §3 for the full reasoning, and NOTICE for the attribution and data-provenance statement.

Aircraft

The engine takes a FlightSource. Two ship here: SimulatedFlights (original, flies real approach and departure corridors) and AdsbFlights (open community ADS-B feeds such as adsb.lol).

FlightRadar24 is deliberately absent — their terms forbid scraping and forbid redistributing their data, so a client for it cannot live in an Apache-2.0 repository. Commercial sources belong in private deployments. The best long-term answer is an RTL-SDR receiver: first-party data with nothing to comply with.

Layout

src/engine/    renderer — terrain, blocks, structures, markers, flights, scene, minimap
src/cities/    data packs — pure geography, no code
src/adapters/  where outside data plugs in
src/tools/     instruments — god-only, dynamically imported, never statically

engine never imports cities; neither imports adapters.

Nothing under src/tools/ may be reached by a static import from the app. It is loaded by one await import() behind access.can.debug, so a visitor who is not an admin does not download the code at all — which is the strongest available reading of "nothing here runs for a non-god visitor": not a hidden panel, not a disabled panel, no panel. src/tools/index.ts states the rule and what silently undoes it.

Licence

Apache License 2.0 — see LICENSE and NOTICE.