Function updateSpring

docs/app/js/sanddance-app.js:87556–87563

(prev, cur, dest, damping, stiffness)

    return spring + damper + velocity + cur;
}
function updateSpring(prev, cur, dest, damping, stiffness) {
    if (Array.isArray(dest)) {
        var next = [];
        for(var i = 0; i < dest.length; i++)next[i] = updateSpringElement(prev[i], cur[i], dest[i], damping, stiffness);
        return next;
    }
    return updateSpringElement(prev, cur, dest, damping, stiffness);
}
function distance(value1, value2) {
    if (Array.isArray(value1)) {
        var distanceSquare = 0;