Sha256: 5904b7426d76776491ae8995d9c74b723460dedee64b4fdb59d77b0211a30a8c
Contents?: true
Size: 1.47 KB
Versions: 4
Compression:
Stored size: 1.47 KB
Contents
function satelliteVertical(P) {
function forward(λ, φ) {
var cosφ = Math.cos(φ),
k = (P - 1) / (P - cosφ * Math.cos(λ));
return [
k * cosφ * Math.sin(λ),
k * Math.sin(φ)
];
}
forward.invert = function(x, y) {
var ρ2 = x * x + y * y,
ρ = Math.sqrt(ρ2),
sinc = (P - Math.sqrt(1 - ρ2 * (P + 1) / (P - 1))) / ((P - 1) / ρ + ρ / (P - 1));
return [
Math.atan2(x * sinc, ρ * Math.sqrt(1 - sinc * sinc)),
ρ ? asin(y * sinc / ρ) : 0
];
};
return forward;
}
function satellite(P, ω) {
var vertical = satelliteVertical(P);
if (!ω) return vertical;
var cosω = Math.cos(ω),
sinω = Math.sin(ω);
function forward(λ, φ) {
var coordinates = vertical(λ, φ),
y = coordinates[1],
A = y * sinω / (P - 1) + cosω;
return [
coordinates[0] * cosω / A,
y / A
];
}
forward.invert = function(x, y) {
var k = (P - 1) / (P - 1 - y * sinω);
return vertical.invert(k * x, k * y * cosω);
};
return forward;
}
function satelliteProjection() {
var P = 1.4,
ω = 0,
m = projectionMutator(satellite),
p = m(P, ω);
// As a multiple of radius.
p.distance = function(_) {
if (!arguments.length) return P;
return m(P = +_, ω);
};
p.tilt = function(_) {
if (!arguments.length) return ω * 180 / π;
return m(P, ω = _ * π / 180);
};
return p;
}
(d3.geo.satellite = satelliteProjection).raw = satellite;
Version data entries
4 entries across 4 versions & 1 rubygems