Sha256: db0f7f87d3915b0ba34f3493a7c41678748fe9615e8b45f79fd90affd1b019a4
Contents?: true
Size: 751 Bytes
Versions: 4
Compression:
Stored size: 751 Bytes
Contents
function mtFlatPolarSinusoidal(λ, φ) {
var A = Math.sqrt(6 / (4 + π)),
k = (1 + π / 4) * Math.sin(φ),
θ = φ / 2;
for (var i = 0, δ; i < 25; i++) {
θ -= δ = (θ / 2 + Math.sin(θ) - k) / (.5 + Math.cos(θ));
if (Math.abs(δ) < ε) break;
}
return [
A * (.5 + Math.cos(θ)) * λ / 1.5,
A * θ
];
}
mtFlatPolarSinusoidal.invert = function(x, y) {
var A = Math.sqrt(6 / (4 + π)),
θ = y / A;
if (Math.abs(Math.abs(θ) - π / 2) < ε) θ = θ < 0 ? -π / 2 : π / 2;
return [
1.5 * x / (A * (.5 + Math.cos(θ))),
asin((θ / 2 + Math.sin(θ)) / (1 + π / 4))
];
};
(d3.geo.mtFlatPolarSinusoidal = function() { return projection(mtFlatPolarSinusoidal); }).raw = mtFlatPolarSinusoidal;
Version data entries
4 entries across 4 versions & 1 rubygems