Off-screen area visualization for 3D orientation based on focus+context and dynamic magnification

Abstract

With the advance in computing power and sensing technology, mobile devices have already become the major platform for augmented reality (AR) and virtual environments (VEs). In particular, location-based mobile augmented reality is rapidly expanding from 2D locations on the ground to indoor and 3D locations due to the prevalence of orientation sensors and computer vision techniques. However, a common limitation of both AR and VEs is a narrow field-of-view (FOV) of the real or virtual camera, which is known to deteriorate task performances. The need for effective overview visualizations for off-screen objects in 3D locations arises from here. Although there exist visualizations for this purpose such as 3D arrows or top-down view radar, many of them suffer from various drawbacks concerning mental rotation, occlusion, or unnatural distortions, which are mainly due to the discordance with human visuospatial perception. In this thesis, we propose Aroundplot, an off-screen area visualization designed for 3D orientation task, which adopts the Focus+Context approach to benefit from the resemblance to the human peripheral vision. One part of the visualization is a noble mapping method from Spherical coordinates to a 2D orthogonal fisheye based on human perception of the reference frame. It combines cylindrical and transverse cylindrical projection in a single mapping so that the cue movements in the visualization closely correspond to the optical flow the user experiences. Another part is a dynamic magnification method of the context in the direction of movement, which restores the context area distortion of fisheye visualizations so as to allow the user more precise control. After then, we conducted user studies consisted of three steps. Firstly an evaluation against two existing visualizations was performed, in which the proposed visualization was shown to be superior in accurately tracking the intended target and similar or better in terms of task speed. The second ...