javascript兑现螺旋数组

javascript实现螺旋数组
javascript版本，可直接粘贴到chrome控制台下运行，
二维数组方式实现最后是一行一行打印的；
支持顺时针和逆时针旋转；
不大喜欢递归，时间空间开销都大，而且还不易修改，算位置的话就纯数学了，我的数学不大好

(function(){    var RIGHT = 0, DOWN = 1, LEFT = 2, UP = 3;//闭包常量    //初始化参数    positonManager = function(length,clockwise){        this.length = length;this.clockwise=clockwise;        this.cx = 0;//当前x坐标        this.cy = 0;//当前y坐标        this.cn = 1;//当前数值        this.cm = clockwise?RIGHT:DOWN;//当前移动方向        this.positions = new Array(length);//空的二维数组        for (var i = 0; i < length; i++) {            this.positions[i] = new Array(length);        }        this.positions[0][0] = ' 1';    }        positonManager.prototype = {        moveNext: function(){            if (this.addNewNum(this.cm)) {//继续上次方向                return true;            }            else                 if (this.addNewNum((this.cm  + (this.clockwise?1:3))%4)) {//因为是个螺旋，转向只能按照固定次序进行循环！                    return true;                }            return false;//无路可走了！        },        //根据方向获取下一地点后判断是否已占位，未占位则赋值，已占位返回false        addNewNum: function(m){            var xy = this.getNewPosition(m);            if (xy !== false && this.positions[xy[1]][xy[0]] == undefined) {                this.cn++;                this.positions[xy[1]][xy[0]] = this.cn < 10 ? ' ' + this.cn : '' + this.cn;                this.cx = xy[0];                this.cy = xy[1];                this.cm = m;                return true;            }            return false;        },        //根据方向获取下一地点，越界返回false        getNewPosition: function(dir){            switch (dir) {                case RIGHT:                    return (this.cx + 1 == this.length ? false : [this.cx + 1, this.cy]);                case DOWN:                    return (this.cy + 1 == this.length ? false : [this.cx, this.cy + 1]);                case LEFT:                    return (this.cx == 0 ? false : [this.cx - 1, this.cy]);                case UP:                    return (this.cy == 0 ? false : [this.cx, this.cy - 1]);            }        },        printAll: function(){            var i, j,line;            while (this.moveNext()){}            for (i=0; i < this.length; i++) {line='';                for (j=0; j < this.length; j++) {                line+=this.positions[i][j]+' ';                }console.log(line);            }        }    }})()console.log('int i=5;');var thread1 = new positonManager(5,false);thread1.printAll();console.log('int i=6;');var thread = new positonManager(6,true);thread.printAll();