[LayaAir 2.0] localToGlobal获取坐标总是错误！

 let buttonTest = this.getChildByName("buttonTest");

        this.sprteCenter = this.getChildByName("sprteCenter");        

        this.boxSpaw = this.getChildByName("boxSpaw");

        //this.spriteSpaw.loadImage("../..")

        buttonTest.on(Laya.Event.CLICK,this,()=>{

            let point = new Laya.Point(this.sprteCenter.x,this.sprteCenter.y);

            let pointGlobal = this.sprteCenter.localToGlobal(point);

            Laya.stage.addChild(this.boxSpaw);

            this.boxSpaw.x = pointGlobal.x;

            this.boxSpaw.y = pointGlobal.y;

            

        })