1. Computer-implemented method for designing a CAD modeled object, wherein the method comprises: displaying several three-dimensional parametric shapes on a screen, wherein each of the several three-dimensional parametric shapes is divided in several portions, a different design operation being assigned to each portion; user-interacting with the screen; determining one portion upon a location of the user-interacting on a support, the determining being performed among all the portions; and performing, on the shape to which the determined portion belongs, the operation assigned to this portion.