global-mercator

Global Mercator

A set of tools geospatial tools to help with TMS, Google (XYZ) Tiles.

This library is insipered by GDAL2Tiles, Google Summer of Code 2007 & 2008

Installation

Using npm:

$ npm install --save global-mercator

In Node.js:

import * as mercator from 'global-mercator'

import { latLngToMeters } from 'global-mercator'

lngLatToMeters

Converts LngLat coordinates to Meters coordinates.

Parameters

• lnglat LngLat LngLat [lng, lat, zoom]
• lng number Longitude (Meridians) in decimal degrees
• lat number Latitude (Parallels) in decimal degrees
• zoom number Zoom level

Examples

const meters = lngLatToMeters([37, 126, 13])
//=meters

Returns Meters Meters coordinates

metersToLngLat

Converts Meters coordinates to LngLat coordinates.

Parameters

• meters Meters Meters [x, y, zoom]
• x number Longitudes (Meridians) in meters
• y number Latitudes (Parallels) in decimal degrees
• zoom number Zoom level

Examples

const lnglat = metersToLngLat([14026255, 4439106, 13])
//=lnglat

Returns LngLat LngLat coordinates

metersToPixels

Converts Meters coordinates to Pixels coordinates.

Parameters

• meters Meters Meters [x, y, zoom]
• x number Longitudes (Meridians) in meters
• y number Latitudes (Parallels) in decimal degrees
• zoom number Zoom level

Examples

const pixels = metersToPixels([14026255, 4439106, 13])
//=pixels

Returns Pixels Pixels coordinates

lngLatToTile

Converts LngLat coordinates to TMS Tile.

Parameters

• lnglat LngLat LngLat [lng, lat, zoom]
• lng number Longitude (Meridians) in decimal degrees
• lat number Latitude (Parallels) in decimal degrees
• zoom number Zoom level

Examples

const tile = lngLatToTile([37, 126, 13])
//=tile

Returns Tile TMS Tile

lngLatToGoogle

Converts LngLat coordinates to Google (XYZ) Tile.

Parameters

• lnglat LngLat LngLat [lng, lat, zoom]
• lng number Longitude (Meridians) in decimal degrees
• lat number Latitude (Parallels) in decimal degrees
• zoom number Zoom level

Examples

const google = lngLatToGoogle({lat: 37, lng: 126, zoom: 13 })
//=google

Returns Google Google (XYZ) Tile

metersToTile

Converts Meters coordinates to TMS Tile.

Parameters

• meters Meters Meters [x, y, zoom]
• x number Longitudes (Meridians) in meters
• y number Latitudes (Parallels) in decimal degrees
• zoom number Zoom level

Examples

const tile = metersToTile([14026255, 4439106, 13])
//=tile

Returns Tile TMS Tile

pixelsToMeters

Converts Pixels coordinates to Meters coordinates.

Parameters

• pixels Pixels Pixels [x, y, zoom]
• x number Pixels X
• y number Pixels Y
• zoom number Zoom level

Examples

const meters = pixelsToMeters([1782579, 1280877, 13])
//=meters

Returns Meters Meters coordinates

pixelsToTile

Converts Pixels coordinates to TMS Tile.

Parameters

• pixels Pixels Pixels [x, y, zoom]
• px number Pixels X
• py number Pixels Y
• zoom number Zoom level

Examples

const tile = pixelsToTile([1782579, 1280877, 13])
//=tile

Returns Tile TMS Tile

tileToBBoxMeters

Converts TMS Tile to bbox in Meters coordinates.

Parameters

• tile Tile Tile [x, y, zoom]
• x number TMS Tile X
• y number TMS Tile Y
• zoom number Zoom level

Examples

const bbox = tileToBBoxMeters([6963, 5003, 13])
//=bbox

Returns BBox bbox extent in [minX, minY, maxX, maxY] order

tileToBBox

Converts TMS Tile to bbox in LngLat coordinates.

Parameters

• tile Tile Tile [x, y, zoom]
• x number TMS Tile X
• y number TMS Tile Y
• zoom number Zoom level

Examples

const bbox = tileToBBox([6963, 5003, 13])
//=bbox

Returns BBox bbox extent in [minX, minY, maxX, maxY] order

googleToBBoxMeters

Converts Google (XYZ) Tile to bbox in Meters coordinates.

Parameters

• google Google Google [x, y, zoom]
• x number Google (XYZ) Tile X
• y number Google (XYZ) Tile Y
• zoom number Zoom level

Examples

const bbox = googleToBBoxMeters([6963, 3188, 13])
//=bbox

Returns BBox bbox extent in [minX, minY, maxX, maxY] order

googleToBBox

Converts Google (XYZ) Tile to bbox in LngLat coordinates.

Parameters

• google Google Google [x, y, zoom]
• x number Google (XYZ) Tile X
• y number Google (XYZ) Tile Y
• zoom number Zoom level

Examples

const bbox = googleToBBox([6963, 3188, 13])
//=bbox

Returns BBox bbox extent in [minX, minY, maxX, maxY] order

tileToGoogle

Converts TMS Tile to Google (XYZ) Tile.

Parameters

• tile Tile Tile [x, y, zoom]
• tx number TMS Tile X
• ty number TMS Tile Y
• zoom number Zoom level

Examples

const google = tileToGoogle([6963, 5003, 13])
//=google

Returns Google Google (XYZ) Tile

googleToTile

Converts Google (XYZ) Tile to TMS Tile.

Parameters

• google Google Google [x, y, zoom]
• x number Google (XYZ) Tile X
• y number Google (XYZ) Tile Y
• zoom number Zoom level

Examples

const tile = googleToTile([6963, 3188, 13])
//=tile

Returns Tile TMS Tile

googleToQuadkey

Converts Google (XYZ) Tile to Quadkey.

Parameters

• google Google Google [x, y, zoom]
• x number Google (XYZ) Tile X
• y number Google (XYZ) Tile Y
• zoom number Zoom level

Examples

const quadkey = googleToQuadkey([6963, 3188, 13])
//=quadkey

Returns string Microsoft's Quadkey schema

tileToQuadkey

Converts TMS Tile to QuadKey.

Parameters

• tile Tile Tile [x, y, zoom]
• tx number TMS Tile X
• ty number TMS Tile Y
• zoom number Zoom level

Examples

const quadkey = tileToQuadkey([6963, 5003, 13])
//=quadkey

Returns string Microsoft's Quadkey schema

quadkeyToTile

Converts Quadkey to TMS Tile.

Parameters

• quadkey string Microsoft's Quadkey schema

Examples

const tile = quadkeyToTile('1321102330211')
//=tile

Returns Tile TMS Tile

quadkeyToGoogle

Converts Quadkey to Google (XYZ) Tile.

Parameters

• quadkey string Microsoft's Quadkey schema

Examples

const google = quadkeyToGoogle('1321102330211')
//=google

Returns Google Google (XYZ) Tile

bboxToMeters

Converts BBox from LngLat coordinates to Meters coordinates

Parameters

• bbox BBox extent in [minX, minY, maxX, maxY] order

Examples

const meters = bboxToMeters([ 125, 35, 127, 37 ])
//=meters

Returns BBox bbox extent in [minX, minY, maxX, maxY] order

resolution

Retrieve resolution based on zoom level

Parameters

• zoom number zoom level

Examples

const res = resolution(13)
//=res

Returns number resolution

validateTile

Validates TMS Tile.

Parameters

• tile Tile Tile [x, y, zoom]
• x number TMS Tile X
• y number TMS Tile Y
• zoom number Zoom level

Examples

validateTile([60, 80, 5])
validateTile([60, -43, 5])
//= Error: Tile <y> must not be less than 0

• Throws Error Will throw an error if TMS Tile is not valid.

Returns Tile TMS Tile

validateZoom

Validates Zoom level.

Parameters

• zoom number Zoom level

Examples

validateZoom(12)
validateZoom(-4)
//= Error: <zoom> cannot be less than 0
validateZoom(32)
//= Error: <zoom> cannot be greater than 30

• Throws Error Will throw an error if zoom is not valid.

Returns number zoom Zoom level

validatePixels

Validates Pixels coordinates.

Parameters

• pixels Pixels Pixels [x, y, zoom]
• x number Pixels X
• y number Pixels Y
• zoom [number] Zoom level

Examples

validatePixels([-115, 44])
//= [-115, 44]

• Throws Error Will throw an error if Pixels is not valid.

Returns Pixels Pixels coordinates

validateMeters

Validates Meters coordinates.

Parameters

• meters Meters Meters [x, y, zoom]
• x number Longitudes (Meridians) in meters
• y number Latitudes (Parallels) in decimal degrees
• zoom [number] Zoom level

Examples

validateMeters([-115, 44])
//= [-115, 44]

• Throws Error Will throw an error if Meters is not valid.

Returns Meters Meters coordinates

validateLngLat

Validates LngLat coordinates.

Parameters

• lnglat LngLat LngLat [lng, lat, zoom]
• lng number Longitude (Meridians) in decimal degrees
• lat number Latitude (Parallels) in decimal degrees
• zoom [number] Zoom level

Examples

validateLngLat([-115, 44])
//= [-115, 44]
validateLngLat([-225, 44])
//= Error: LngLat [lng] must be within -180 to 180 degrees

• Throws Error Will throw an error if LngLat is not valid.

Returns LngLat LngLat coordinates

range

Generate an integer Array containing an arithmetic progression. A port of the native Python range() function. See the Python documentation.

Parameters

• start [number] Start (optional, default 0)
• stop number Stop
• step [number] Step (optional, default 1)

Examples

range(20)
range(10, 20)
range(20, 10, -1)

Returns Array<number> range

Changelog

1.0.0 - 2016-10-01

First Stable release was created