Log-Aesthetic (LA) curve has been claimed as one of a most promising curve for design purpose. However, LA curve has no shape variable which can be used to control its end curvatures directly. Generalized Log-Aesthetic Curve (GLAC) which is the family of LA curve has ability to control its curvature with an extra shape parameter. This paper highlights on designing two segments of GLACs in the form of C-and S-shapes with curvature continuity using interior point method. Designers will be able to design S-shapes and C-shapes by inputting control points, its direction of travel and estimated end curvatures.