Sha256: 88cc490630b429a6553fa0d9192ebb3cc6a4725e2cf0a80cad5674e42a970cc1
Contents?: true
Size: 759 Bytes
Versions: 4
Compression:
Stored size: 759 Bytes
Contents
// @import mollweide
function boggs(λ, φ) {
var k = 2.00276,
θ = mollweideθ(φ);
return [
k * λ / (1 / Math.cos(φ) + 1.11072 / Math.cos(θ)),
(φ + Math.SQRT2 * Math.sin(θ)) / k
];
}
boggs.invert = function(x, y) {
var k = 2.00276,
ky = k * y,
θ = y < 0 ? -π / 4 : π / 4, i = 25, δ, φ;
do {
φ = ky - Math.SQRT2 * Math.sin(θ);
θ -= δ = (Math.sin(2 * θ) + 2 * θ - π * Math.sin(φ)) / (2 * Math.cos(2 * θ) + 2 + π * Math.cos(φ) * Math.SQRT2 * Math.cos(θ));
} while (Math.abs(δ) > ε && --i > 0);
φ = ky - Math.SQRT2 * Math.sin(θ);
return [
x * (1 / Math.cos(φ) + 1.11072 / Math.cos(θ)) / k,
φ
];
};
(d3.geo.boggs = function() { return projection(boggs); }).raw = boggs;
Version data entries
4 entries across 4 versions & 1 rubygems