UNPKG

node-red-contrib-tak-registration

Version:

A Node-RED node to register to TAK and to help wrap files as datapackages to send to TAK

55 lines 1.74 kB
// index.ts import { coordEach } from "@turf/meta"; import { isNumber } from "@turf/helpers"; import { clone } from "@turf/clone"; function toMercator(geojson, options = {}) { return convert(geojson, "mercator", options); } function toWgs84(geojson, options = {}) { return convert(geojson, "wgs84", options); } function convert(geojson, projection, options = {}) { options = options || {}; var mutate = options.mutate; if (!geojson) throw new Error("geojson is required"); if (Array.isArray(geojson) && isNumber(geojson[0])) geojson = projection === "mercator" ? convertToMercator(geojson) : convertToWgs84(geojson); else { if (mutate !== true) geojson = clone(geojson); coordEach(geojson, function(coord) { var newCoord = projection === "mercator" ? convertToMercator(coord) : convertToWgs84(coord); coord[0] = newCoord[0]; coord[1] = newCoord[1]; }); } return geojson; } function convertToMercator(lonLat) { var D2R = Math.PI / 180, A = 6378137, MAXEXTENT = 20037508342789244e-9; var adjusted = Math.abs(lonLat[0]) <= 180 ? lonLat[0] : lonLat[0] - sign(lonLat[0]) * 360; var xy = [ A * adjusted * D2R, A * Math.log(Math.tan(Math.PI * 0.25 + 0.5 * lonLat[1] * D2R)) ]; if (xy[0] > MAXEXTENT) xy[0] = MAXEXTENT; if (xy[0] < -MAXEXTENT) xy[0] = -MAXEXTENT; if (xy[1] > MAXEXTENT) xy[1] = MAXEXTENT; if (xy[1] < -MAXEXTENT) xy[1] = -MAXEXTENT; return xy; } function convertToWgs84(xy) { var R2D = 180 / Math.PI; var A = 6378137; return [ xy[0] * R2D / A, (Math.PI * 0.5 - 2 * Math.atan(Math.exp(-xy[1] / A))) * R2D ]; } function sign(x) { return x < 0 ? -1 : x > 0 ? 1 : 0; } export { toMercator, toWgs84 }; //# sourceMappingURL=index.js.map