vection

gistfile1.js

var vection = (function () {

    function vection(){
        return vection.create.apply(vection, [].slice.call(arguments));
    }
    
    function _extend( target, base) {
        for (var key in base) {
            if ({}.hasOwnProperty.call(base, key)) {
                target[key] = base[key];
            }
        }
        return target;
    }

    var undefined, _create = Object.create || function (obj) {
        function F() {}
        F.prototype = obj;
        return new F;
    };

    _extend(vection, {
        create: function( left, top) {
            var neu = _create( this.prototype);
            neu.left = typeof left == "object" ? left.left : (left || 0);
            neu.top = typeof left == "object" ? left.top : (top || 0);
            
            return neu;
        },
        is: function (obj) {
            return this.prototype.isPrototypeOf(obj);
        },
        parse: function( str){
            var left = /left:\s*(\d+)/.exec( str), 
                top= /top:\s*(\d+)/.exec( str);
            return vection.create(+(left&&left[1]), +(top&&top[1]));
        }
    });

    _extend(vection.prototype, {
        left: 0,
        top: 0,
        clone: function(){
            return vection.create( this);
        },
        scale: function (lambda) {
            var neu = this.clone();
            neu.left *= lambda;
            neu.top *= lambda;
            return neu;
        },
        add: function( a, b){
            var neu = vection.create( a, b);
            neu.left += this.left;
            neu.top += this.top;
            return neu;
        },
        sub: function( a, b){
            return vection.create( a, b).scale(-1).add(this);
        },
        normalize: function(){
            return this.scale(1/this.magnitude());
        },
        magnitude: function(){
            return Math.sqrt( this.left* this.left+ this.top* this.top);
        },
        manhattan: function(){
            return Math.abs( this.left) + Math.abs( this.top);
        },
        toCSS: function( unit){
            return "left: "+this.left+(unit||"px")+"; top:"+this.top+(unit||"px")+" ;";
        }
    });

    return vection;
})();