foobar2000算法总结

未解

function StrFmt(alignH, alignV, trim, flag) {
    return ((alignH << 28) | (alignV << 24) | (trim << 20) | flag);
}

时间戳转时分秒字符串

function TimeFmt(t) {
    if (t < 0) return "00:00:00";
    var zpad = function(n) {
            var str = n.toString();
            return (str.length < 2) ? "0" + str : str;
        }
    var h = Math.floor(t / 3600);
    t -= h * 3600;
    m = Math.floor(t / 60);
    t -= m * 60, s = Math.floor(t);
    return zpad(h) + ":" + zpad(m) + ":" + zpad(s);
}

格式化HMS

function Format_hms(t) {
    if (t=="?") return "00:00:00";
    var hms;
    if (t) {
        switch (t.length) {
        case 4:
            hms = "00:0" + t;
            break;
        case 5:
            hms = "00:" + t;
            break;
        case 7:
            hms = "0" + t;
            break;
        default:
            hms = t;
            break;
        }
        return hms;
    } else {
        return "00:00:00";
    }
}

计算音量大小与位置关系算法,未解

function pos2vol(p) {
    return (50 * Math.log(0.99 * (p / 100) + 0.01) / Math.log(10));
}


function vol2pos(v) {
    return Math.round(((Math.pow(10, v / 50) - 0.01) / 0.99) * 100);
}

windows实现互斥单选按钮：

var MF_STRING = 0x00000000;
var MF_DISABLED = 0x00000002;
var PBOTips = new Array("默认", "重复(列表)", "重复(音轨)", "随机", "乱序(音轨)", "乱序(专辑)", "乱序(目录)");
PBO_Menu = function(x, y) {
    var PBOmenu = window.CreatePopupMenu();
    var menu_item_count = 0;
    for (var i = 0; i < PBOTips.length; i++)
    PBOmenu.AppendMenuItem(MF_STRING, ++menu_item_count, PBOTips[i]);
    PBOmenu.CheckMenuRadioItem(1, menu_item_count, fb.PlayBackOrder + 1);
    var ret = 0;
    ret = PBOmenu.TrackPopupMenu(x, y, 0x0020);
    if (ret) {
        switch (ret) {
        default:
            fb.PlaybackOrder = ret - 1;
            PBOmenu.CheckMenuRadioItem(1, menu_item_count, ret);
            break;
        }
    }
    PBOmenu.Dispose();
}

？？？？CheckMenuRadioItem方法不太懂