35 lines
915 B
Java
35 lines
915 B
Java
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import parallel1 from "./parallel1";
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import {abs, cos, epsilon, halfPi, log, quarterPi, tan} from "./math";
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export function loximuthalRaw(phi0) {
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var cosPhi0 = cos(phi0),
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tanPhi0 = tan(quarterPi + phi0 / 2);
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function forward(lambda, phi) {
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var y = phi - phi0,
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x = abs(y) < epsilon ? lambda * cosPhi0
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: abs(x = quarterPi + phi / 2) < epsilon || abs(abs(x) - halfPi) < epsilon
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? 0 : lambda * y / log(tan(x) / tanPhi0);
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return [x, y];
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}
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forward.invert = function(x, y) {
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var lambda,
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phi = y + phi0;
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return [
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abs(y) < epsilon ? x / cosPhi0
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: (abs(lambda = quarterPi + phi / 2) < epsilon || abs(abs(lambda) - halfPi) < epsilon) ? 0
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: x * log(tan(lambda) / tanPhi0) / y,
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phi
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];
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};
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return forward;
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}
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export default function() {
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return parallel1(loximuthalRaw)
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.parallel(40)
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.scale(158.837);
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}
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