Object selection is the basis of natural user–computer interaction (NUI) in a virtual environment (VE). Among the three-dimensional object selection techniques employed in virtual reality (VR), bare hand-based finger clicking interaction and ray-casting are two convenient approaches with a high level of acceptance. This study involved 14 participants, constructed a virtual laboratory environment in VR, and compared the above two finger-based interaction techniques in terms of aspects of the task performance, including the success rate, total reaction time, operational deviation, and accuracy, at different spatial positions. The results indicated that the applicable distance range of finger clicking interaction and finger ray-casting was 0.2 to 1.4 m and over 0.4 m, respectively. Within the shared applicable distance, the finger clicking interaction achieved a shorter total reaction time and higher clicking accuracy. The performance of finger clicking interaction varied remarkably at the center and edge of the horizontal field of view, while no significant difference was found among ray-casting at various horizontal azimuths. The current findings could be directly applied to the application of bare-hand interaction in VR environments.

In virtual reality, users’ input and output interactions are carried out in a three-dimensional space, and bare-hand click interaction is one of the most common interaction methods. Apart from the limitations of the device, the movements of bare-hand click interaction in virtual reality involve head, eye, and hand movements. Consequently, clicking performance varies among locations in the binocular field of view. In this study, we explored the optimal interaction area of hand–eye coordination within the binocular field of view in a 3D virtual environment (VE), and implemented a bare-hand click experiment in a VE combining click performance data, namely, click accuracy and click duration, following a gradient descent method. The experimental results show that click performance is significantly influenced by the area where the target is located. The performance data and subjective preferences for clicks show a high degree of consistency. Combining reaction time and click accuracy, the optimal operating area for bare-hand clicking in virtual reality is from 20° to the left to 30° to the right horizontally and from 15° in the upward direction to 20° in the downward direction vertically. The results of this study have implications for guidelines and applications for bare-hand click interaction interface designs in the proximal space of virtual reality.

Multisize geographic information system (GIS) has widely used in social life, and the introduction of natural interactive methods such as gesture interaction further broadens the applications of GIS. Gestures, as a natural means of expression, bring a convenient experience to the use of GIS. The user-elicitation method can determine the user’s original operational intention and take advantage of the natural and convenient gesture interaction. However, current research on elicitation methods mainly focuses on defining the function factors of operation commands and rarely considers the influence of environmental factors such as spatial sizes. This paper takes GIS as the object, which is closely related to multisize space. This paper reports a research project on user-defined gestures for interacting with two-dimensional maps in a virtual reality environment, including three types of GIS operation commands and six sizes of maps. The results showed that the user-defined gestures for the same GIS operation commands varied across map sizes. The increase in map size increased the amount of gestural movement. Drawing on our research, we developed a set of gestures for multisize GIS interface interaction. We hope that this research can provide a guiding foundation for mid-air gesture design for all multisize interfaces.