大转盘

最近写的一个大转盘的页面，感觉还挺有趣的。在写之前也是百度找相关资料，然后整合成自己喜欢的样子。
下面是代码部分：

 <div class="num-box" id="lottery">
                    <table>
                        <tr>
                            <td class="box active lottery-unit lottery-unit-0">
                                <a href="javascript:;">
                                <img src="img/fee.png" alt="" />
                                </a>
                            </td>
                            <td class="box lottery-unit lottery-unit-1">
                                <a href="javascript:;">
                                <font class="num">50</font>
                                <p class="inner-text">积分</p>
                                </a>
                            </td>
                            <td class="box lottery-unit lottery-unit-2">
                                <a href="javascript:;">
                                <font class="num">8元</font>
                                <p class="inner-text">优惠券</p>
                                </a>
                            </td>
                        </tr>
                        <tr>
                            <td class="box lottery-unit lottery-unit-7">
                                <a href="javascript:;">
                                <font class="num">5元</font>
                                <p class="inner-text">优惠券</p>
                                </a>
                            </td>
                            <td class="btn-start"><a href="javascript:;"></a></td>
                            <td class="box lottery-unit lottery-unit-3">
                                <a href="javascript:;">
                                <font class="num">1元</font>
                                <p class="inner-text">优惠券</p>
                                </a>
                            </td>
                        </tr>
                        <tr>
                            <td class="box lottery-unit lottery-unit-6">
                                <a href="javascript:;">
                                <font class="num">10</font>
                                <p class="inner-text">积分</p>
                                </a>
                            </td>
                            <td class="box lottery-unit lottery-unit-5">
                                <a href="javascript:;">
                                <font class="num">10元</font>
                                <p class="inner-text">优惠券</p>
                                </a>
                            </td>
                            <td class="box lottery-unit lottery-unit-4">
                                <a href="javascript:;">
                                <font class="num">谢谢</font>
                                <font class="num">参与</font>
                                </a>
                            </td>
                        </tr>
                    </table>
                </div>

var lottery={
    index:-1,   //当前转动到哪个位置，起点位置
    count:0,    //总共有多少个位置
    timer:0,    //setTimeout的ID，用clearTimeout清除
    speed:20,   //初始转动速度
    times:0,    //转动次数
    cycle:50,   //转动基本次数：即至少需要转动多少次再进入抽奖环节
    prize:-1,   //中奖位置
    init:function(id){
        if ($("#"+id).find(".lottery-unit").length>0) {
            $lottery = $("#"+id);
            $units = $lottery.find(".lottery-unit");
            this.obj = $lottery;
            this.count = $units.length;
            $lottery.find(".lottery-unit-"+this.index).addClass("active");
        };
    },
    roll:function(){
        var index = this.index;
        var count = this.count;
        var lottery = this.obj;
        $(lottery).find(".lottery-unit-"+index).removeClass("active");
        index += 1;
        if (index>count-1) {
            index = 0;
        };
        $(lottery).find(".lottery-unit-"+index).addClass("active");
        this.index=index;
        return false;
    },
    stop:function(index){
        this.prize=index;
        return false;
    }
};

function roll(){
    lottery.times += 1;
    lottery.roll();
    if (lottery.times > lottery.cycle+10 && lottery.prize==lottery.index) {
        clearTimeout(lottery.timer);
        lottery.prize=-1;
        lottery.times=0;
        click=false;
    }else{
        if (lottery.times<lottery.cycle) {
            lottery.speed -= 10;
        }else if(lottery.times==lottery.cycle) {
            var index = Math.random()*(lottery.count)|0;
            lottery.prize = index;      
        }else{
            if (lottery.times > lottery.cycle+10 && ((lottery.prize==0 && lottery.index==7) || lottery.prize==lottery.index+1)) {
                lottery.speed += 110;
            }else{
                lottery.speed += 20;
            }
        }
        if (lottery.speed<40) {
            lottery.speed=40;
        };
        //console.log(lottery.times+'^^^^^^'+lottery.speed+'^^^^^^^'+lottery.prize);
        lottery.timer = setTimeout(roll,lottery.speed);
    }
    return false;
}

var click=false;

window.onload=function(){
    lottery.init('lottery');
    $("#lottery .btn-start a").click(function(){
        if (click) {
            return false;
        }else{
            lottery.speed=100;
            roll();
            click=true;
            return false;
        }
    });
};