Combined the contour lines sketching and the mesh modeling technology,an efficient modeling approach is proposed.First,according to the distribution of the critical points on contour line,the constraint-based triangulation is implemented and the skeleton of contour lines is extracted.Furthermore,it projects the skeleton onto ellipsoid surfaces,and then it optimizes the triangulation algorithm from discrete points by adopting the rule of dihedral angel.Finally,the 3D mesh model is created by stitching the sk...