Abstract: We propose a method that allows geometric operations such as view change, deformation, simulation, or symmetrization on a single off-line sketch via a proxy geometry reconstructed directly from the sketch. The reconstruction captures the overall shape of the object depicted by making use of the global relationships of the curvesand the assumption that the sketched object is bilaterally symmetric. After cleaning the sketch and extracting the curves, topological and geometric properties of a set of identified points are used to derive robust correspondence and pairwise constraints. These constraints are considered all at once in a spectral algorithm to get the optimum matching of the curves. Depths of points on the matched curves are extracted by utilizing the symmetry assumption. They are then used to reconstruct a smooth geometry. The whole process is automatic except for a few seconds of user interaction.