Function centroidRingPoint

docs/app/js/sanddance-app.js:132356–132367

(lambda, phi)

    centroidPointCartesian(x0, y0, z0);
}
function centroidRingPoint(lambda, phi) {
    lambda *= (0, _mathJs.radians), phi *= (0, _mathJs.radians);
    var cosPhi = (0, _mathJs.cos)(phi), x = cosPhi * (0, _mathJs.cos)(lambda), y = cosPhi * (0, _mathJs.sin)(lambda), z = (0, _mathJs.sin)(phi), cx = y0 * z - z0 * y, cy = z0 * x - x0 * z, cz = x0 * y - y0 * x, m = (0, _mathJs.hypot)(cx, cy, cz), w = (0, _mathJs.asin)(m), v = m && -w / m; // area weight multiplier
    X2.add(v * cx);
    Y2.add(v * cy);
    Z2.add(v * cz);
    W1 += w;
    X1 += w * (x0 + (x0 = x));
    Y1 += w * (y0 + (y0 = y));
    Z1 += w * (z0 + (z0 = z));
    centroidPointCartesian(x0, y0, z0);
}
exports.default = function(object) {
    W0 = W1 = X0 = Y0 = Z0 = X1 = Y1 = Z1 = 0;
    X2 = new (0, _d3Array.Adder)();