Cloning objects is a common operation in graphical user interfaces. A good example is calendar systems, where users commonly create and modify recurring events, i.e. repeated clones of a single event. Inspired by the calendar paradigm, we introduce a new cloning technique for 2D drawing programs. This technique allows users to clone objects by first selecting them and then dragging them to create clones along the dragged path. A novel approach for the generation of clones of clones is also presented. Moreover, the technique enables editing of the generated sequences of clones similar to the editing of calendar events.
We compared our new clone creation technique with generic duplication via copy-and-paste, smart duplication, and a dialog driven technique on a desktop system. The results show that the new cloning method is always faster than dialogs and faster than smart duplication for most conditions. We also compared our clone editing method against rectangular selection. The results show that our method is better in general. In situations where rectangle selection is effective, our method is still competitive. Participants preferred the new techniques overall, too.