@affino/world-map-core

Headless world map core types and utilities for reusable Affino world map features.

This package has no UI, renderer, Vue, React, DOM, SVG, Canvas, WebGL, MapLibre, D3, topojson, or chart dependencies.

Core

import { createWorldMapCore } from "@affino/world-map-core"

const core = createWorldMapCore()
// { version: "0.1.0" }

Country Features

import type { WorldMapCountryFeature } from "@affino/world-map-core"

const feature: WorldMapCountryFeature = {
  id: "US",
  name: "United States",
  iso2: "US",
  iso3: "USA",
  geometry: {
    type: "Polygon",
    coordinates: [[
      { lon: -124.7844, lat: 24.7433 },
      { lon: -66.9514, lat: 24.7433 },
      { lon: -66.9514, lat: 49.3458 },
    ]],
  },
}

Projection

import { projectWorldMapPosition } from "@affino/world-map-core"

const point = projectWorldMapPosition(
  { lon: 0, lat: 0 },
  { viewport: { width: 360, height: 180 } },
)

// { x: 180, y: 90 }

The default projection is equirectangular.

Path Data

import { createWorldMapPath } from "@affino/world-map-core"

const pathFeature = createWorldMapPath(feature, {
  viewport: { width: 360, height: 180 },
  precision: 2,
  antimeridianStrategy: "break-lines",
})

// { id, name, iso2, iso3, path, properties }

Polygon and MultiPolygon rings are projected with the selected projection and emitted as SVG path data. Empty rings are skipped.

By default, paths use antimeridianStrategy: "break-lines" to unwrap rings that cross the antimeridian. Compact edge-crossing rings may emit shifted copies at the map edges to preserve local closure, while larger mainland rings keep the primary visible copy to avoid duplicating whole countries outside the viewport. Use antimeridianStrategy: "none" to preserve direct line commands across the antimeridian.

Non-Goals For v0.1

• No renderer components.
• No DOM, SVG, Canvas, or WebGL integration.
• No MapLibre, D3, topojson, or chart dependencies.
• No Mercator projection yet.
• No fit-to-bounds, zoom, pan, or topology processing yet.