果实出不来，也没有报错是怎么回事，求指教
var fruitObj = function ()
{
this.alive = [];//bool
this.x = [];
this.y = [];
this.l = [];
this.spd = [];
this.fruitType = [];
this.orange = new Image();
this.blue = new Image();
}
fruitObj.prototype.num = 30;
fruitObj.prototype.init = function()
{
for( var i = 0;i < this.num; i++)
{
this.alive[i] = false;
this.x[i] = 0;
this.y[i] = 0;
this.spd[i] = Math.random()*0.017 + 0.003;//[0.003,0.02)
this.fruitType[i] = "";
}
this.orange.src = "./src/fruit.png";
this.blue.src= "./src/blue.png";
}
fruitObj.prototype.draw = function()
{
for(var i=0; i < this.num; i++)
{
//draw
//find an ane,grow,fly up
if(this.alive[i])
{
if(this.fruitType[i] == "blue")
{
var pic = this.blue;
}
else
{
var pic = this.orange;
}
if(this.l[i] <= 14)
{
this.l[i] += this.spd[i] * deltaTime;
}
else
{
this.y[i] -=this.spd[i] * 7 * deltaTime;
}
ctx2.drawImage(pic,this.x[i] - this.l[i] * 0.5,this.y[i] - this.l[i] * 0.5,this.l[i],this.l[i]);
if(this.y[i] < 10)
{
this.alive[i] = false;
}
}
}
}
fruitObj.prototype.born = function(i)
{
var aneId= Math.floor(Math.random()*ane.num)
this.x[i] = ane.x[aneId];
this.y[i] = canHeight - ane.len[aneId];
this.l[i] = 0;
this.alive = true;
var ran = Math.random();
if(ran < 0.2)
{
this.fruitType[i] = "blue";
}
else
{
this.fruitType[i] = "orange";
}
}
function fruitMonitor()
{
var num = 0;
for(var i = 0; i < fruit.num; i++)
{
if(fruit.alive[i]){
num++;
}
}
if(num < 15)
{
//send fruit
sendFruit();
return;
}
}
function sendFruit()
{
for(var i = 0; i<fruit.num;i++)
{
if(!fruit.alive[i])
{
fruit.born(i);
return;
}
}
}
