Files
openlayers/src/ol/proj/proj4.js
2017-12-15 19:17:29 +01:00

52 lines
1.4 KiB
JavaScript

/**
* @module ol/proj/proj4
*/
import {addCoordinateTransforms, addProjection, addEquivalentProjections, get} from '../proj.js';
import {get as getTransform} from './transforms.js';
import Projection from './Projection.js';
/**
* Make projections defined in proj4 (with `proj4.defs()`) available in
* OpenLayers.
*
* This function should be called whenever changes are made to the proj4
* registry, e.g. after calling `proj4.defs()`. Existing transforms will not be
* modified by this function.
*
* @param {?} proj4 Proj4.
* @api
*/
export function register(proj4) {
var projCodes = Object.keys(proj4.defs);
var len = projCodes.length;
var i, j;
for (i = 0; i < len; ++i) {
var code = projCodes[i];
if (!get(code)) {
var def = proj4.defs(code);
addProjection(new Projection({
code: code,
axisOrientation: def.axis,
metersPerUnit: def.to_meter,
units: def.units
}));
}
}
for (i = 0; i < len; ++i) {
var code1 = projCodes[i];
var proj1 = get(code1);
for (j = 0; j < len; ++j) {
var code2 = projCodes[j];
var proj2 = get(code2);
if (!getTransform(code1, code2)) {
if (proj4.defs[code1] === proj4.defs[code2]) {
addEquivalentProjections([proj1, proj2]);
} else {
var transform = proj4(code1, code2);
addCoordinateTransforms(proj1, proj2, transform.forward, transform.inverse);
}
}
}
}
}