@morphemeris/armilla-map-maplibre

The MapLibre GL JS adapter for armilla's astrocartography line model (spec §12.2): draws predicate-honoring ACG lines, glyph + designation labels, and the birthplace marker over a tiled basemap. Library choice rationale: plinth/research/map-library-survey.md.

The package is standalone at runtime — no dependency on @morphemeris/armilla-core (its MapLine types are structural mirrors, drift-pinned by compat.test.ts) and none on maplibre-gl (the overlay uses a structural MapLike subset of the map, also compat-pinned), so it hosts on any compatible map version.

Use

import { mapLines } from '@morphemeris/armilla-core';
import { AcgOverlay } from '@morphemeris/armilla-map-maplibre';

map.on('load', () => {
  const overlay = new AcgOverlay(map); // after `load`: layers need a style
  overlay.setModel(mapLines(chartInput, viewState, environment));
  overlay.setPlace({ latitude: 51.4779, longitude: 0 });
});

// View-state rules changed? Recompute — hidden lines are already omitted,
// dim/emphasize ride each line and the default styling applies them.
overlay.setModel(mapLines(chartInput, nextViewState, environment));

overlay.remove(); // removes every source, layer, element, and listener it added

Options (AcgOverlayOptions): idPrefix, scheme (light | dark palette), labels, lineStyle(line) to replace the default theme-mirroring styles, labelElement(line) to replace the default glyph + designation label. Labels are .armilla-acg-label elements and the place marker is .armilla-acg-place — style them with CSS.

Labels follow the viewport: on every map move each label re-anchors to its line's visible stretch — the MC/IC meridians pin a label just inside the top and bottom edges at the line's longitude, curves ride their center-nearest visible vertex — and a label hides only while its line is out of view. Hovering a line emphasizes it (width +1, full opacity, pointer cursor) and bolds its labels, which also gain .armilla-acg-label-hover for custom styling.

Demo

demo/index.html shows the acg fixture's 50 lines over OpenFreeMap tiles:

pnpm --filter @morphemeris/armilla-core build:wasm   # once, if the WASM artifact is stale
pnpm build && pnpm gen:demo              # dist + demo/model.json
python -m http.server 8741               # from this package directory
# open http://localhost:8741/demo/