Transform coordinates between various coordinate systems used in Bulgaria.
- Info
- Install
- Ellipsoids
- Projections
- Examples
- Transform between geographic coordinates and projected in Lambert projection
- Transform between geographic coordinates and projected in UTM
- Transform between geographic coordinates and projected in Gauss–Krüger
- Transform between geographic coordinates and projected in Web Mercator
- Transform between geographic and geocentric coordinates
- Transform between BGS coordinates
- Format decimal degrees from/to degrees, minutes and seconds
- Dependencies
- Tests
- License
This project is based on Transformations.NET library.
The project can be used for transforming coordinates between various coordinate systems:
- BGS 1930
- BGS 1950
- BGS Sofia
- BGS 1970 (there can be no control points near by if the point is close to the zone's border)
- BGS 2005
Following projections are available:
- Lambert Conformal Conic with 2SP
- Universal Transverse Mercator
- Gauss–Krüger
- Spherical Web Mercator
You can transform between:
- Geographic coordinates
- Projected coordinates
- Geocentric coordinates
Transformations between BGS coordinate systems are done by calculating transformation parameters using TPS or Affine transformation based on predefined control points (ControlPoints namespace). You can control what type of transformation is used by passing useTPS
boolean parameter to BGSCoordinates.transform()
. All other transformations are done directly as the transformation parameters are known. Precision is arround 10cm
.
You can install it with NPM (npm install transformations
) or Yarn (yarn add transformations
) and then import a desired transformation function:
import { transformGeographicToUTM } from 'transformations';
const input = [42.450682, 24.749747];
const result = transformGeographicToUTM(input);
import { ellipsoids } from 'transformations';
- GRS80 - GRS 1980
- BESSEL_1841 - Bessel 1841
- CLARKE_1866 - Clarke 1866
- EVEREST - Everest (Sabah and Sarawak)
- HELMERT - Helmert 1906
- HAYFORD - Hayford
- KRASSOVSKY - Krassovsky, 1942
- WALBECK - Walbeck
- WGS72 - WGS 1972
- WGS84 - WGS 1984
- SPHERE - Normal Sphere (R=6378137)
import { projections } from 'transformations';
- BGS_SOFIA - BGS Sofia. Local projection based on BGS 1950
- BGS_1930_24 - Gauss–Krüger projection based on Hayford ellipsoid
- BGS_1930_27 - Gauss–Krüger projection based on Hayford ellipsoid
- BGS_1950_3_24 - Gauss–Krüger projection based on Krassovsky ellipsoid
- BGS_1950_3_27 - Gauss–Krüger projection based on Krassovsky ellipsoid
- BGS_1950_6_21 - Gauss–Krüger projection based on Krassovsky ellipsoid
- BGS_1950_6_27 - Gauss–Krüger projection based on Krassovsky ellipsoid
- BGS_1970_K3 - ~ Northewest Bulgaria
- BGS_1970_K5 - ~ Southeast Bulgaria
- BGS_1970_K7 - ~ Northeast Bulgaria
- BGS_1970_K9 - ~ Southwest Bulgaria
- BGS_2005_KK - Lambert Conformal Conic with 2SP used by Cadastral Agency
- UTM34N - Universal Transverse Mercator zone 34 North
- UTM35N - Universal Transverse Mercator zone 35 North
import { transformGeographicToLambert, transformLambertToGeographic } from 'transformations';
let input = [42.7589996, 25.3799991];
let result = transformGeographicToLambert(input);
// result is: 4735953.342, 490177.508
let input = [4735953.349, 490177.508;
let result = transformLambertToGeographic(input);
// result is: 42.7589997, 25.3799991
import { transformGeographicToUTM, transformUTMToGeographic } from 'transformations';
let input = [42.450682, 24.749747];
let result = transformGeographicToUTM(input);
// result is: 4702270.178, 314955.869
let input = [4702270.179, 314955.869];
let result = transformUTMToGeographic(input);
// result is: 42.450682, 24.749747
import { transformGeographicToGauss, transformGaussToGeographic } from 'transformations';
let input = [42.7602978166667, 25.3824052611111];
let result = transformGeographicToGauss(input);
// result is: 4736629.503, 8613154.606
let input = [4736629.503, 8613154.607);
let result = transformGaussToGeographic(input);
// result is: 42.7602978, 25.38240528
import { transformGeographicToWebMercator, transformWebMercatorToGeographic } from 'transformations';
let input = [42.450682, 24.749747];
let result = transformGeographicToWebMercator(input);
// result is: 2755129.233, 5228730.328
let input = [2755129.23, 5228730.33];
let result = transformWebMercatorToGeographic(input);
// result is: 42.4506820, 24.7497470
import { transformGeographicToGeocentric, transformGeocentricToGeographic } from 'transformations';
let input = [42.450682, 24.749747];
let result = transformGeographicToGeocentric(input);
// result is: X: 4280410.654, 1973273.422, 4282674.061
let input = [4280410.654, 1973273.422, 4282674.061];
let result = transformGeocentricToGeographic(input);
// result is: 42.450682, 24.749747
- BGS 1930
import { BGSCoordinates } from 'transformations';
const bgs = new BGSCoordinates();
let input = [4728966.163, 8607005.227];
let result = bgs.transform(input, projections.BGS_1930_24, projections.BGS_2005_KK);
// result is: 4728401.432, 483893.508
let input = [4728401.432, 483893.508];
let result = bgs.transform(input, projections.BGS_2005_KK, projections.BGS_1930_24);
// result is: 4728966.153, 8607005.214
- BGS 1950
import { BGSCoordinates } from 'transformations';
const bgs = new BGSCoordinates();
let input = [4729331.175, 8606933.614];
let result = bgs.transform(input, projections.BGS_1950_3_24, projections.BGS_2005_KK);
// result is: 4728401.442, 483893.521
let input = [4728401.432, 483893.508];
let result = tr.transform(input, projections.BGS_2005_KK, projections.BGS_1950_3_24);
// result is: 4729331.165, 8606933.601
- BGS Sofia
import { BGSCoordinates } from 'transformations';
const bgs = new BGSCoordinates();
let input = [48276.705, 45420.988];
let result = bgs.transform(input, projections.BGS_SOFIA, projections.BGS_2005_KK);
// result is: 4730215.221, 322402.929
let input = [4730215.229, 322402.935];
let result = bgs.transform(input, projections.BGS_2005_KK, projections.BGS_SOFIA);
// result is: 48276.713, 45420.993
- BGS 1970
import { BGSCoordinates } from 'transformations';
const bgs = new BGSCoordinates();
let input = [4725270.684, 8515734.475];
let result = bgs.transform(input, projections.BGS_1970_K3, projections.BGS_2005_KK);
// result is: 4816275.688, 332535.346
let input = [4816275.68, 332535.401];
let result = bgs.transform(input, projections.BGS_2005_KK, projections.BGS_1970_K3);
// result is: 4725270.677, 8515734.530
let input = [4613479.192, 9493233.633];
let result = bgs.transform(input, projections.BGS_1970_K5, projections.BGS_2005_KK);
// result is: 4679669.824, 569554.912
let input = [4679669.825, 569554.918];
let result = bgs.transform(input, projections.BGS_2005_KK, projections.BGS_1970_K5);
// result is: 4613479.193, 9493233.639
let input = [4708089.898, 9570974.988];
let result = bgs.transform(input, projections.BGS_1970_K7, projections.BGS_2005_KK);
// result is: 4810276.410, 626498.618
let input = [4810276.431, 626498.611];
let result = bgs.transform(input, projections.BGS_2005_KK, projections.BGS_1970_K7);
// result is: 4708089.919, 9570974.981
let input = [4547844.976, 8508858.179];
let result = bgs.transform(input, projections.BGS_1970_K9, projections.BGS_2005_KK);
// result is: 4675440.859, 330568.410
let input = [4675440.847, 330568.434];
let result = bgs.transform(input, projections.BGS_2005_KK, projections.BGS_1970_K9);
// result is: 4547844.965, 8508858.203
Use this method to calculate transformation parameters once and apply them to all input points.
You can either pass an extent, for which the transformation parameters will be calculated:
let extent = [4515891.16322039, 8471284.82458501, 4565579.62520789, 8551929.53794741];
let result = bgs.transformArray([...], projections.BGS_1970_K9, projections.BGS_2005_KK, true, extent);
or just pass the points and use the bounding extent:
let result = bgs.transformArray([...], projections.BGS_1970_K9, projections.BGS_2005_KK, true);
*Use TPS transformation as it gives better accuracy.
import { convertDecimalDegreesToDMS, convertDMStoDecimalDegrees } from 'transformations';
let latitude = 42.336542;
let dms = convertDecimalDegreesToDMS(latitude);
// dms is: "422011.5512000000052"
let dms = '422011.5512000000052';
let result = convertDMStoDecimalDegrees(dms);
// result is: 42.336542
Check tests for more examples.
transformations is MIT License @ bojko108