var fruitObj = function() {
    this.alive = [];
    this.x = [];
    this.y = [];
    this.l=[];
    this.spd=[];
    this.orange = new Image();
    this.blue = new Image();
}
fruitObj.prototype.num = 30;
fruitObj.prototype.init = function() {
    for(var i = 0; i < this.num; i++) {
        // 定义果实生命期为true，说白了就是显示
        this.alive[i] = true;
        this.x[i] = 0;
        this.y[i] = 0;
        this.spd[i] = Math.random() * 0.01 + 0.005;
        // 遍历30次，分别得到这30次果实的位置
        this.born(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++) {
        if(this.alive[i]){
            // 绘制果实的图片以及位置
            if(this.l[i]<=15){
                this.l[i] +=deltaTime * this.spd[i];
            }else {
                this.y[i]-=this.spd[i] * 5 * deltaTime;
            }
            ctx2.drawImage(this.orange, 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) {
    // ane.num == 50
    var aneID = Math.floor(Math.random() * ane.num);
    // 使每个果实的横坐标对应每个海葵的横坐标
    this.x[i] = ane.x[aneID];
    // 使每个果实的纵坐标刚好在每个海葵的上面
    this.y[i] = canHeight - ane.len[aneID];
    this.l[i]=0;
}