@basemaps/geo

Utility functions to work with QuadKeys, Tiles and Projections.

Bounds and intersections

import { Bounds } from '@basemaps/geo';

const bounds = new Bounds(128, 128, 256, 256);
const boundsB = new Bounds(0, 0, 256, 256);

bounds.intersects(boundsB); // true

bounds.intersection(boundsB); // { x: 128, y: 128, width: 128, height: 128}

Typing for generic point and sizes

import { Point, Size, BoundingBox } from '@basemaps/geo';

const p: Point = { x: 5, y: 5 };
const s: Size = { width: 200, height: 500 };
const box: BoundingBox = { ...p, ...s };

QuadKey utilities

import {QuadKey} from '@basemaps/geo';


QuadKey.children('3') // ['30', '31', '32', '33']

QuadKey.fromTile({ x: 3, y: 2, z: 2 } // '31'

Tile Matrix Sets

import { GoogleTms } from '@basemaps/geo/build/tms/google';

/** Convert tile offsets into pixel coordinates */
GoogleTms.tileToPixels(1, 1); // { x: 256, y: 256 }

/** Convert a tile into the upper left point in Google  */
GoogleTms.tileToSource({ x: 0, y: 0, z: 0 }); // { x: -20037508.3427892, y: 20037508.3427892 }

Epsg Helpers

import { Epsg } from '@basemaps/geo';

Epsg.Google.toEpsgCode(); // `EPSG:3857`
Epsg.Google.toUrn(); // `urn:ogc:def:crs:EPSG:3857`
Epsg.parse('3857'); // Epsg.Google
Epsg.get(3857); // Epsg.Google