The quadbin-js
is a TypeScript library for working with the Quadbin spatial index.
npm install quadbin
import {cellToParent, getResolution, hexToBigInt} from 'quadbin';
cellToParent(5210915457518796799n) // => 5206425052030959615n
getResolution(hexToBigInt('4830ffffffffffff')) // => 3
A Quadbin index is a 64-bit integer. This library uses BigInt as a data type to represent quadbin indices, both as parameters and return values for functions.
When working with quadbin indices in other contexts (e.g. passing as a parameter in a URL or serializing as JSON), it is more appropriate to encode the index as a hexidecimal string. The library provides the bigIntToHex()
& hexToBigInt()
to facilitate this conversion.
function bigIntToHex(index: bigint): string
Encodes an index into a string, suitable for use in JSON.
function hexToBigInt(hex: string): bigint
Decodes an string into an index. Inverse of bigIntToHex()
.
function getResolution(quadbin: bigint): bigint
Calculates the resolution of a quadbin cell.
function cellToParent(quadbin: bigint): bigint
Calculates the parent cell.
function tileToCell(tile: {x: number, y: number, z: number}): bigint
Converts a xyz tile into a quadbin cell.
function cellToTile(quadbin: bigint): Tile
Converts quadbin cell into a xyz tile.
function geometryToCells(geometry: GeoJSONGeometry, resolution: bigint): bigint
Returns a list of cells covering a GeoJSON geometry at a given resolution