The Effect of Target Depth on Performance of Multi-directional Tapping Task in Virtual Reality

While widely used to evaluate 2D pointing performance, adapting the multi-directional tapping task (ISO/TS 9241-411) to virtual reality (VR) poses challenges, particularly in addressing target depth.This study examines how depth affects user performance in the multi-directional tapping task in VR.We conducted a within-subject experiment with 20 participants, investigating the effect of various depths (0.5-100 m for Raycasting; 0.3-0.6 m for Virtual Hand) under consistent visual angles.Results showed that Raycasting performance remained stable beyond 2 m but degraded significantly at 0.5 m, while Virtual Hand performed best between 0.4 and 0.5 m and declined at closer and farther depths.These findings suggest that target depth strongly influences selection performance even when visual angles remain consistent, underscoring the need for considering standardized depth parameters in VR pointing protocols.We also provide evidence-based recommendations for implementing depth parameters in future VR studies using the multi-directional tapping task.