Sha256: 17896997387892d78b4168807f4fe65d0baf3bb1080ba3a3851e26c1ccb9a4e7
Contents?: true
Size: 1.28 KB
Versions: 5
Compression:
Stored size: 1.28 KB
Contents
(function() {
var ρ = Math.SQRT2,
ρ2 = 2,
ρ4 = 4;
// p0 = [ux0, uy0, w0]
// p1 = [ux1, uy1, w1]
d3.interpolateZoom = function(p0, p1) {
var ux0 = p0[0], uy0 = p0[1], w0 = p0[2],
ux1 = p1[0], uy1 = p1[1], w1 = p1[2];
var dx = ux1 - ux0,
dy = uy1 - uy0,
d2 = dx * dx + dy * dy,
d1 = Math.sqrt(d2),
b0 = (w1 * w1 - w0 * w0 + ρ4 * d2) / (2 * w0 * ρ2 * d1),
b1 = (w1 * w1 - w0 * w0 - ρ4 * d2) / (2 * w1 * ρ2 * d1),
r0 = Math.log(Math.sqrt(b0 * b0 + 1) - b0),
r1 = Math.log(Math.sqrt(b1 * b1 + 1) - b1),
dr = r1 - r0,
S = (dr || Math.log(w1 / w0)) / ρ;
function interpolate(t) {
var s = t * S;
if (dr) {
// General case.
var coshr0 = cosh(r0),
u = w0 / (ρ2 * d1) * (coshr0 * tanh(ρ * s + r0) - sinh(r0));
return [
ux0 + u * dx,
uy0 + u * dy,
w0 * coshr0 / cosh(ρ * s + r0)
];
}
// Special case for u0 ~= u1.
return [
ux0 + t * dx,
uy0 + t * dy,
w0 * Math.exp(ρ * s)
];
}
interpolate.duration = S * 1000;
return interpolate;
};
function cosh(x) {
return (Math.exp(x) + Math.exp(-x)) / 2;
}
function sinh(x) {
return (Math.exp(x) - Math.exp(-x)) / 2;
}
function tanh(x) {
return sinh(x) / cosh(x);
}
})();
Version data entries
5 entries across 5 versions & 1 rubygems