Two novel off-screen navigation techniques
In large workspaces that do not fit on the screen space, users have to navigate to various regions outside the viewport to locate items of interest. Researchers have developed a variety of different navigation techniques to improve the performance of working with large workspaces. In this thesis I design, implement, and evaluate two novel navigation techniques to access off-screen content. I call these techniques Multiscale Window and Crystal Ball. The design of these two techniques was based on two hybrid interaction systems WinHop and Multiscale Zoom. Multiscale Window takes advantage of Multiscale Zoom to provide an overview of the context by incorporating full-detail object representations (proxies), and Crystal Ball is an improvement to WinHop. The implemented techniques were designed to alleviate the shortcomings of both hybrid techniques; Multiscale Zoom lacks the ability to provide detail information of overlapped proxies, and WinHop does not facilitate navigation to the off-screen region due to the animation. I evaluated the Multiscale Window and Crystal Ball techniques in two experiments. In the first experiment (N = 14) a Tablet PC with a digital pen as an input device was used. Results showed that there was no significant difference between Multiscale Window and Multiscale Zoom. However, Crystal Ball showed improved effects over WinHop in most tasks. The second experiment (N = 14) compared the same techniques as in experiment one, on a PC with a mouse as input device. The results indicated that subjects were faster with Crystal Ball than WinHop. Like the first experiment, Multiscale Window did not show any significant improvement over Multiscale Zoom.
navigation, large workspace