1. In a digital environment rendering spline-based designs, a method of enhancing curves, the method comprising: detecting, by at least one processor, user input defining points of at least a portion of a spline; non-uniformly scaling, by the at least one processor, a curve in the spline in a single direction; identifying, by the at least one processor, end point constraints from the non-uniformly scaled curve; computing, by the at least one processor, multiple cubic variation of curvature (CVC) curves corresponding to the identified end point constraints; and downscaling, by the at least one processor, the multiple CVC curves while maintaining the end point constraints to generate an enhanced curve in the spline.