A typeface processing application accesses a character skeleton, which has control points and curves defined by control points, and a character outline surrounding the character skeleton. The typeface processing application computes, for a design parameter of a design application, a graphics control dataset based on a particular control point. Doing so involves identifying a pair of control point positions and a pair of expansions of the character outline, where each position or expansion pair corresponds to a pair of design parameter values. The typeface processing application generates the graphics control dataset, which includes intermediate positions of the control point between the pair of positions and intermediate expansions of the character outline between the pair of expansions. The typeface processing application outputs the graphics control dataset to the design application, which can display, responsive to a selection of a design parameter value, modified character designs generated using the graphics control dataset.