kea-geo/src/tileToLat.js

Collection of geo related utility

// source: https://wiki.openstreetmap.org/wiki/Slippy_map_tilenames#ECMAScript_.28JavaScript.2FActionScript.2C_etc..29

module.exports = function (y, zoom) {
  const n = Math.PI - 2 * Math.PI * y / Math.pow(2, zoom)
  return (180 / Math.PI * Math.atan(0.5 * (Math.exp(n) - Math.exp(-n))))
}