(function() {

    var libutil= {};

    libutil.isNumber=function(v) {
        return typeof v === "number";
    };

    libutil.clamp=function(val, min, max) {
        if(window.EnableDebugMode) {
            if(max<min) {
                console.warn("ibutil.clamp(): the max value is less than the min value");
                var min1 = Math.min(min, max);
                var max1 = Math.max(min, max);
                return Math.min(Math.max(val, min1), max1);
            }
        }
        return Math.min(Math.max(val, min), max);
    };

    libutil.calcresize=function(cw, ch, ratio) { // return=[width,height,left,top]
        if(cw/ch<ratio) {
            var h=cw/ratio;
            return [cw, h, 0, (ch-h)/2];
        } else {
            var w=ch*ratio;
            return [w, ch, (cw-w)/2, 0];
        }
    };

    window.libutil=libutil;

})();