Drawing connections: Designing situated links for immersive maps

We explore the design of situated visual links in outdoor augmented reality (AR) for connecting miniature buildings on a virtual map to their real-world counterparts. We first distill design criteria from prior work, then conduct two user studies to evaluate a set of proposed link designs to better understand users' preferences for different design choices of the links. In two user studies we evaluated, respectively, a set of link geometries in a virtual environment and a refined AR prototype in two different outdoor environments. The studies reveal that links help in identifying buildings in the environments. Participants prefer straight rather than curved links, simple and thin links to avoid information occlusion, and links and maps aligned with their direction of view. We recommend using a consistent color with a strong contrast to the background color for all links in a scene. To improve visibility, the diameter of links should grow with distance to the viewer and optional animated stripes can be placed on links. The findings of this study have the potential to bolster the development of various situated visualization applications, such as those used in urban planning, tourism, smart agriculture, and other fields.