怎么把贪吃蛇中的正方形食物改成别的图形

按照网上教程做了一个贪吃蛇，想要优化优化



 public class Bean
    {public Bean()
        {
            //TODO:在此处添加构造函数逻辑
        }


        private const int unitlength = 5;//定义符号常量单位长度
        private Point origin;//定义位置字段
        public  Point Origin
        {
            get { return origin; }
            set { origin = value; }
        }
        public void Display(Graphics g)//显示豆方法
        {
            SolidBrush brush = new SolidBrush(Color.Blue  );//定义红色画刷
            g.FillRectangle(brush, origin.X, origin.Y, unitlength, unitlength);//画实心矩形

        }

        public void UnDisplay(Graphics g)//消除豆方法
        {
            SolidBrush brush = new SolidBrush(Color.Silver);//定义背景色画刷
            g.FillRectangle(brush, origin.X, origin.Y, unitlength, unitlength);//用背景色重画原来矩形即消除原矩形
        }
    }
}