Function world2LatLng

src/lib/index.js:18–27

({ x, y })

}

function world2LatLng({ x, y }) {
  const n = Math.PI - 2 * Math.PI * y;

  // TODO test that this is faster
  // 360 * Math.atan(Math.exp((180 - y * 360) * Math.PI / 180)) / Math.PI - 90;
  return {
    lat: (180 / Math.PI) * Math.atan(0.5 * (Math.exp(n) - Math.exp(-n))),
    lng: x * 360 - 180,
  };
}

// Thank you wiki https://en.wikipedia.org/wiki/Geographic_coordinate_system
function latLng2MetersPerDegree({ lat }) {