找了好久都找不到错误啊....

var WINDOW_WIDTH=1024;

var WINDOW_HEIGHT=768;

var MARGIN_LEFT=30;

var MARGIN_TOP=60;

var RADIUS=8;

const endTime=new Date(2015,9,12,10,10,10);

var curshowTimeSeconds=0;

var Balls=[];

const colors=["#33B5E5","#0099CC","#AA66CC","#9933CC","#99CC00","#669900","#FFBB33","#FF8800","#FF4444","#CC0000"]

window.onload=function(){

var canvas=document.getElementById('canvas');

var context=canvas.getContext("2d");

canvas.height=WINDOW_HEIGHT;

canvas.width=WINDOW_WIDTH;

    curshowTimeSeconds=getcurshowTimeSeconds()

    setInterval(

    function(){

    render(context);

    update();

    },

    50

    );

}

function getcurshowTimeSeconds(){

var curTime=new Date();

var ret=endTime.getTime()-curTime.getTime();

ret=Math.round(ret/1000);

return ret>=0 ?ret:0;

}

function update(){

 var nextshowTimeSeconds=getcurshowTimeSeconds();

 var nexthours=parseInt(nextshowTimeSeconds/3600);

 var nextminutes=parseInt((nextshowTimeSeconds-nexthours*3600)/60);

 var nextseconds=nextshowTimeSeconds%60;

 var curhours=parseInt(curshowTimeSeconds/3600);

 var curminutes=parseInt((curshowTimeSeconds-curhours*3600)/60);

 var curseconds=curshowTimeSeconds%60;

    if(curseconds!=nextseconds){

        if(parseInt(curhours/10)!=parseInt(nexthours/10))

        { addBalls(MARGIN_LEFT,MARGIN_TOP,parseInt(hours/10))};

        if(parseInt(curhours%10)!=parseInt(nexthours%10))

        { addBalls(MARGIN_LEFT+15*(RADIUS+1),MARGIN_TOP,parseInt(hours%10))};

        if(parseInt(curminutes/10)!=parseInt(nextminutes/10))

        { addBalls(MARGIN_LEFT+39*(RADIUS+1),MARGIN_TOP,parseInt(minutes/10))};

        if(parseInt(curminutes%10)!=parseInt(nextminutes%10))

        { addBalls(MARGIN_LEFT+54*(RADIUS+1),MARGIN_TOP,parseInt(minutes%10))};

        if(parseInt(curseconds/10)!=parseInt(nextseconds/10))

        { addBalls(MARGIN_LEFT+78*(RADIUS+1),MARGIN_TOP,parseInt(seconds%10))};

        if(parseInt(curseconds%10)!=parseInt(nextseconds%10))

        { addBalls(MARGIN_LEFT+93*(RADIUS+1),MARGIN_TOP,parseInt(seconds%10))};

    curshowTimeSeconds=nextshowTimeSeconds;

    }

    updateBalls();

}

function updateBalls(){

for(var i=0;i<Balls.length;i++){

 Balls[i].x+=Balls[i].vx;

 Balls[i].y+=Balls[i].vy;

 Balls[i].vy+=Balls[i].g;

       if(Balls[i].y>=WINDOW_HEIGHT-RADIUS){

           Balls[i].y=WINDOW_HEIGHT-RADIUS;

           Balls[i].vy= - Balls[i].vy*0.75

       }

}

}

function addBalls(x,y,num){

for(var i=0;i< digit[num].length;i++)

    for(var j=0;j< digit[num][i].length;j++)

    if(digit[num][i][j]==1){

        var aBall={

            x:x+2*j*(RADIUS+1)+(RADIUS+1),

            y:y+2*i*(RADIUS+1)+(RADIUS+1),

            g:1.5+Math.random(),

            vx:Math.pow(-1,Math.ceil(Math.radom()*1000))*4,

            vy:-5,

            color:colors[Math.floor(Math.random()*colors.length)]    

 }

        Balls.push( aBall );

}

function render( cxt ){

    cxt.clearRect(0,0,WINDOW_WIDTH,WINDOW_HEIGHT);

    var hours = parseInt(curshowTimeSeconds/3600 );

    var minutes = parseInt((curshowTimeSeconds-hours*3600)/60);   

    var seconds = curshowTimeSeconds%60

    renderDigit(margin_left, margin_top, parseInt(hours / 10), cxt);

        renderDigit(margin_left + 15 * (radius + 1), margin_top, parseInt(hours % 10), cxt);

        renderDigit(margin_left + 30 * (radius + 1), margin_top, 10, cxt);

        renderDigit(margin_left + 39 * (radius + 1), margin_top, parseInt(minutes / 10), cxt);

        renderDigit(margin_left + 54 * (radius + 1), margin_top, parseInt(minutes % 10), cxt);

        renderDigit(margin_left + 69 * (radius + 1), margin_top, 10, cxt);

        renderDigit(margin_left + 78 * (radius + 1), margin_top, parseInt(seconds / 10), cxt);

        renderDigit(margin_left + 93 * (radius + 1), margin_top, parseInt(seconds % 10), cxt);

        for (var i = 0; i < balls.length; i++) {

    cxt.fillStyle=Balls[i].color;

    cxt.beginPath();

    cxt.arc(Balls[i].x,Balls[i].y,RADIUS,0,2*Math.PI,ture);

    cxt.closePath();

    cxt.fill();

    }

}

function renderDigit( x , y , num , cxt ){

    cxt.fillStyle = "blue";

    for( var i = 0 ; i < digit[num].length ; i ++ )

        for(var j = 0 ; j < digit[num][i].length ; j ++ )

            if( digit[num][i][j] == 1 ){

                cxt.beginPath();

                cxt.arc( x+j*2*(RADIUS+1)+(RADIUS+1) , y+i*2*(RADIUS+1)+(RADIUS+1) , RADIUS , 0 , 2*Math.PI )

                cxt.closePath()

                cxt.fill()

            }

}