19 lines
527 B
JavaScript
19 lines
527 B
JavaScript
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import {geoProjection as projection} from "d3-geo";
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import {asin, pi, sin, sqrt, sqrtPi} from "./math";
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export function collignonRaw(lambda, phi) {
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var alpha = sqrt(1 - sin(phi));
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return [(2 / sqrtPi) * lambda * alpha, sqrtPi * (1 - alpha)];
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}
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collignonRaw.invert = function(x, y) {
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var lambda = (lambda = y / sqrtPi - 1) * lambda;
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return [lambda > 0 ? x * sqrt(pi / lambda) / 2 : 0, asin(1 - lambda)];
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};
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export default function() {
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return projection(collignonRaw)
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.scale(95.6464)
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.center([0, 30]);
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}
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