pseudomerc

const proj4 = require('proj4'); const turf = require('@turf/turf'); // from https://epsg.io/3857 const PSEUDO_MERC_DATUM = "+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +wktext +no_defs"; // from https://epsg.io/4326 const WGS84_DATUM = "+proj=longlat +datum=WGS84 +no_defs"; const xyCoordsToLatLong = (xy_pair) => { return proj4(PSEUDO_MERC_DATUM, WGS84_DATUM, xy_pair); } const latLongCoordsToXY = (latlong_pair) => { return proj4(WGS84_DATUM, PSEUDO_MERC_DATUM, latlong_pair); } const xyToLatLonBBOX = (xy_bbox, return_as_poly = false) => { const bbox_poly = turf.bboxPolygon(xy_bbox); bbox_poly.geometry.coordinates = [bbox_poly.geometry.coordinates[0].map(pair => xyCoordsToLatLong(pair))]; return return_as_poly ? bbox_poly : turf.bbox(bbox_poly); } const latLongToXYbbox = (latlon_bbox, return_as_poly = false) => { const bbox_poly = turf.bboxPolygon(latlon_bbox); bbox_poly.geometry.coordinates = [bbox_poly.geometry.coordinates[0].map(pair => latLongCoordsToXY(pair))]; return return_as_poly ? bbox_poly : turf.bbox(bbox_poly); } console.info('validate', xyToLatLonBBOX(latLongToXYbbox([-82, 35, -74, 42]))); console.info('visualize geojson', xyToLatLonBBOX(latLongToXYbbox([-82, 35, -74, 42]), true));