A summary spline curve can be constructed from multiple animation spline curves. Control points for each of the animation spline curves can be included to form a combined set of control points for the summary spline curve. Each of the animation spline curves can then be divided into spline curve segments between each neighboring pair of control points in the combined set of control points. For each neighboring pair, the spline curve segments can be normalized and averaged to determine a summary spline curve segment. These summary spline curve segments are combined to determine a summary spline curve. The summary spline curve can then be displayed and/or modified. Modifications to the summary spline curve can result in modifications to the animation spline curves.