Simplifying collaboration in co-located virtual environments using the active-passive approach

The design and implementation of co-located immersive virtual environments with equal interaction possibilities for all participants is a complex topic. The main problem, on a fundamental technical level, is the difficulty of providing perspective-correct images for each participant. There is consensus that the lack of a correct perspective view will negatively affect interaction fidelity and therefore also collaboration. Several research approaches focus on providing a correct perspective view to all participants to enable co-located work. However, these approaches are usually either based on custom hardware solutions that limit the number of users with a correct perspective view or software solutions striving to eliminate or mitigate restrictions with custom image-generation approaches. In this paper we investigate an often overlooked approach to enable collaboration for multiple users in an immersive virtual environment designed for a single user. The approach provides one (active) user with a perspective-correct view while other (passive) users receive visual cues that are not perspective-correct. We used this active-passive approach to investigate the limitations posed by assigning the viewpoint to only one user. The findings of our study, though inconclusive, revealed two curiosities. First, our results suggest that the location of target geometry is an important factor to consider for designing interaction, expanding on prior work that has studied only the relation between user positions. Secondly, there seems to be only a low cost involved in accepting the limitation of providing perspective-correct images to a single user, when comparing with a baseline, during a coordinated work approach. These findings advance our understanding of collaboration in co-located virtual environments and suggest an approach to simplify co-located collaboration.