Principal stress lines are pairs of orthogonal curves that indicate trajectories of internal forces and can be used as idealized paths for material continuity, which can be translated to structural ribs. This method and graphical interface enables the exploration of a range of structural ribs topologies and layouts for any given set of boundary conditions. The method visualizes and enables designers to choose from various stress line topologies for input boundary conditions (such as force loads, perimeter of the part, and support positions ). Once the desired stress line topology is selected, it allows automatic regeneration of a less dense version of the stress line topology to be selected as idealized paths of material continuity for the structure. This new network of curves is then automatically translated to parametric ribs and shells using the mesh alignment method. This comprehensive parametric algorithm thus allows modification of structural ribs topology by varying its profile along a path, and automatically parametrically explores thin shells from concave to flat.