>private int scaleFactor = 1;
>public int ScaleFactor
>        {
>            get { return scaleFactor; }
>            set
>            {
>                if (value == 0)
>                {
>                    scaleFactor = scaleFactor == 1 ? -1 : 1;
>                }
>                else
>                    scaleFactor = value;
>            }
>        }

int i = --ScaleFactor;