A well-designed control-to-display (CD) gain function can improve pointing performance with an indirect pointing device such as a trackpad. However, the design of gain functions has been challenging and mostly based on trial and error. AutoGain is an unobtrusive method to obtain a gain function for an indirect pointing device in contexts where cursor trajectories can be tracked. It gradually improves pointing efficiency by using a novel submovement-level tracking+optimization technique. In a study, we show that AutoGain can produce gain functions with performance comparable to commercial designs in less than a half hour of active use. This is attributable to reductions in aiming error (undershooting/overshooting) for each submovement. Our second study shows that AutoGain can be used to obtain gain functions for emerging input devices (here, a Leap Motion controller) for which no good gain function may exist yet. Finally, we discuss deployment in a real interactive system.
['Byungjoo Lee', 'Mathieu Nancel', 'Antti Oulasvirta']
AutoGain: Adapting Gain Functions by Optimizing Submovement Efficiency