Function pointToTile

src/utils.js:26–50

(lon, lat, z, projection, order)

}

export const pointToTile = (lon, lat, z, projection, order) => {
  const z2 = Math.pow(2, z)

  let tile
  switch (projection) {
    case 'mercator':
      tile = pointToCamera(lon, lat, z, projection)
      break
    case 'equirectangular':
      let x = z2 * (lon / 360 + 0.5)
      let y = z2 * ((order[1] * -1 * lat) / 180 + 0.5)

      x = x % z2
      if (x < 0) x = x + z2
      y = Math.max(Math.min(y, z2), 0)
      tile = [x, y, z]
      break
    default:
      return
  }
  tile[0] = Math.floor(tile[0])
  tile[1] = Math.min(Math.floor(tile[1]), z2 - 1)

  return tile
}

export const pointToCamera = (lon, lat, z) => {
  const sin = Math.sin(lat * d2r)