Function cartesianCross

docs/app/js/sanddance-app.js:132255–132261

(a, b)

    return a[0] * b[0] + a[1] * b[1] + a[2] * b[2];
}
function cartesianCross(a, b) {
    return [
        a[1] * b[2] - a[2] * b[1],
        a[2] * b[0] - a[0] * b[2],
        a[0] * b[1] - a[1] * b[0]
    ];
}
function cartesianAddInPlace(a, b) {
    a[0] += b[0], a[1] += b[1], a[2] += b[2];
}