if(!Engine){
    throw new Error("Engine is not loaded");
}

Engine.DebugEngine = (()=>{

    class DebugEngine extends Engine{
        constructor(){
            super();
            this._frames = 0;
            this._fpsClock = new Engine.StopWatch();
        }
        Update(){
            let ms = this._fpsClock.ElapsedMilliseconds;
            let s = ms/1000;
            if(this._fpsClock.ElapsedMilliseconds >= 1000){
                console.log("DebugEngine:::FPS = ", this._frames/s);
                this._frames = 0;
                this._fpsClock.Restart();
            }
            this._frames++;
            super.Update();
        }
        Run(){
            super.Run();
            this._fpsClock.Start();
        }
        Stop(){
            super.Stop();
            this._fpsClock.Stop();
            this._fpsClock.Reset();
        }
    }


    return DebugEngine;

})();