A computer-implement operating method includes periodically generating sensing data by determining a triggered area of each of the sensors of a surface on which each of the sensors disposed; grouping effective sensors among the sensors into a plurality of sensor groups respectively corresponding to the fingers; obtaining a bending angle of one finger among the fingers according to the sensing values of the sensing data of all effective sensors in one sensor group corresponding to the said one finger among the sensor groups; and bending one virtual finger corresponding to the said one finger among virtual fingers of a virtual hand rendered in a virtual space corresponding to the electronic system according to the obtained bending angle of the said one finger, so as to render the virtual hand having a gesture matching to a gesture of the hand sensed by the controller.