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/* * * Orthographic projection * */ 'use strict'; /* * * * Constants * * */ const deg2rad = Math.PI / 180, scale = 63.78460826781007; /* * * * Class * * */ class Orthographic { constructor() { /* * * * Properties * * */ this.antimeridianCutting = false; this.bounds = { x1: -scale, x2: scale, y1: -scale, y2: scale }; } /* * * * Functions * * */ forward(lonLat) { const lonDeg = lonLat[0], latDeg = lonLat[1], lat = latDeg * deg2rad, xy = [ Math.cos(lat) * Math.sin(lonDeg * deg2rad) * scale, Math.sin(lat) * scale ]; if (lonDeg < -90 || lonDeg > 90) { xy.outside = true; } return xy; } inverse(xy) { const x = xy[0] / scale, y = xy[1] / scale, z = Math.sqrt(x * x + y * y), c = Math.asin(z), cSin = Math.sin(c), cCos = Math.cos(c); return [ Math.atan2(x * cSin, z * cCos) / deg2rad, Math.asin(z && y * cSin / z) / deg2rad ]; } } /* * * * Default Export * * */ export default Orthographic;