A method for manipulating the control points of a symbol image represented by an outline font to improve the appearance of the font on raster output devices which are under control of a computer. The method includes storing control points specifying the outlines of a symbol image, specifying the desired movement direction defined by a first unit vector in which the control point should move, and specifying a desired measurement direction defined by a second unit vector by which the movement of the control point should be measured. The desired measurement direction and the desired movement direction forming an angle of predetermined size. The method further includes moving the control points in the desired movement direction and measuring the control points against the predetermined angle with the desired measurement direction, this measurement producing a resulting movement direction and storing the results of the manipulation of the control points in a memory.