Introduction to the Special Issue on SAP 2022

This special issue of ACM Transactions on Applied Perception (TAP) showcases three articles from the 19th Symposium on Applied Perception (SAP), held virtually in September 2022. ACM SAP provides an intimate forum for researchers who combine knowledge, methods, and insights from perception research and computer science disciplines. This includes disciplines such as cognitive psychology, perceptual psychology, psychophysics, behavior-analysis, and neuroscience on the perceptual side and computer graphics, computer vision, visualization, virtual reality, and human-computer interfaces on the visual computing side.

This year SAP received 22 complete submissions that followed a double-blind procedure. A total of 13 papers were accepted for presentation at the conference, and from those, 3 papers were selected to appear in this Special Issue due to their outstanding quality. After a second round of reviews, in accordance with the journal’s traditional review process, they were accepted for publication in this journal. We thank the program committee members for their additional work in shepherding these selected papers.

The article entitled Sensitivity to Hand Offsets and Related Behavior in Virtual Environments over Time [1], authored by Kristopher Kohm, John Porter, and Andrew Robb (Clemson University), explores how exposure time affects users’ sensitivities to spatial offsets in their avatars’ hands in virtual reality. This study reveals that, while it is not clear whether users become more sensitive to these spatial offset changes, they do show behavioral changes in terms of head–hand coordination and completion time as users gain exposure to virtual reality.

The article entitled Experience Matters: Longitudinal Changes in Sensitivity to Rotational Gains in Virtual Reality [2], authored by Andrew Robb, Kristopher Kohm, and John Porter (Clemson University), measures how users’ sensitivity to rotational gains in virtual reality changes as they gain experience in virtual reality. The conclusions suggest that users become more sensitive to rotation gains over time, which is a very important factor to take into account in applications involving redirected walking techniques.

The article entitled Investigating a Combination of Input Modalities, Canvas Geometries, and Inking Triggers on On-air Handwriting in Virtual Reality [3], authored by Roshan Venkatakrishnan, Rohith Venkatakrishnan (Clemson University), Chih-Han Chung (National Yang Ming Chiao Tung University), Sabarish V. Babu (Clemson University), and Yu-Shuen Wang (National Yang Ming Chiao Tung University), investigates the effects of different factors that can potentially influence users’ on-air handwriting performance in virtual reality. Their results revealed that using a brush produces the best results when compared to near-field ray-casting and pointing gestures, that haptic feedback is not always effective compared to a button-based trigger, and that there are tradeoffs in performance depending on different types of canvas geometries.

We would like to thank the reviewers who provided insightful and timely evaluations of the works presented in this special issue of TAP and the ACM TAP editor-in-chief, Bobby Bodenheimer, who was also integral to the successful and timely publication of this issue. The ACM publications staff and Stephen Spencer should also be thanked for their efforts. This special issue would not exist without the hard work that each of these individuals contributed.

We hope you enjoy these articles and encourage you to take a look at the SAP 2022 proceedings on the ACM Digital Library.