1. A character generating method for generating a bit map image of a character of a designated size from outline data of said character, said method comprising the steps of: converting each piece of outline coordinate data expressing a contour line of said character in logical coordinates, into coordinates of said designated size; replacing converted coordinates of designated points on said contour line with coordinates on a reference line determined by coordinates of specific reference points; rounding said individual converted coordinates of said contour and converting said rounded coordinates line into physical coordinates expressed by integers; and generating a bit map image of said character from said converted physical coordinates.