1. A computer-implemented method comprising: detecting a first series of data points obtained from a sketch input module, the first series of data points representing user stroke data obtained from the sketch input module; matching the first series of data points with a geometry; generating a recognition result corresponding to the matching geometry, the recognition result comprising a recognized geometry and an assisting geometry, the recognized geometry having a boundary corresponding to the first series of data points and the assisting geometry being a geometric extension of the recognized geometry; simultaneously displaying the first series of data points and the recognition result through a user interface; detecting a second series of data points obtained from the sketch input module, the second series of data points representing a continuation of the user stroke data obtained from the sketch input module; responsive to detecting the second series of data points, updating the recognized geometry based on a deviation of the second series of data points from the assisting geometry; and simultaneously displaying the second series of data points and the recognition result with the updated recognized geometry through the user interface.