JS: daytimeColor

more at: http://stackoverflow.com/a/19780902/1250044 http://stackoverflow.com/a/258106/1250044

by Yannick Albert

JavaScript

var parseColor = function (start, end, now) {
    return [
        start[0] + now * (end[0] - start[0]) | 0,
        start[1] + now * (end[1] - start[1]) | 0,
        start[2] + now * (end[2] - start[2]) | 0,
        (start[3] && end[3]) ? (start[3] + now * (end[3] - start[3]) | 0) : 1
    ];
};

var daytimeColor = function (start, end, date) {
    date = date || new Date();
    var hour = date.getHours();
    var minute = date.getMinutes();
    var now = hour * minute / 1440;
    var rgba = parseColor(start, end, now);

    return 'rgba(' + rgba.join() + ')';
};

var start = [150, 225, 255];
var end = [50, 50, 255];
document.body.style.backgroundColor = daytimeColor(start, end);