_proto_.moveDownBall = function(){
this.ball.x -= this.vx;
this.ball.y += this.vy;
console.log("111111");
this.vy *= 0.99;
this.vy += 0.25;
console.log("222222");
if (this.ball.y + this.vy >= this.stageHeight ||this.ball.y + this.vy <= 0) {
this.vy = -this.vy;
}
if (this.ball.x + this.vx >= this.stageWidth ||this.ball.x + this.vx <= 0) {
this.vx = -this.vx;
}
