29 lines
681 B
Java
29 lines
681 B
Java
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import {geoProjection as projection} from "d3-geo";
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import {asin, atan2, cos, sin, sqrt, tan} from "./math";
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export function wagner7Raw(lambda, phi) {
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var s = 0.90631 * sin(phi),
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c0 = sqrt(1 - s * s),
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c1 = sqrt(2 / (1 + c0 * cos(lambda /= 3)));
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return [
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2.66723 * c0 * c1 * sin(lambda),
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1.24104 * s * c1
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];
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}
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wagner7Raw.invert = function(x, y) {
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var t1 = x / 2.66723,
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t2 = y / 1.24104,
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p = sqrt(t1 * t1 + t2 * t2),
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c = 2 * asin(p / 2);
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return [
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3 * atan2(x * tan(c), 2.66723 * p),
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p && asin(y * sin(c) / (1.24104 * 0.90631 * p))
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];
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};
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export default function() {
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return projection(wagner7Raw)
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.scale(172.632);
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}
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