On Virtual Pointing Rays and Motion Artefacts

Virtual pointing rays are a commonly employed interaction metaphor allowing users of mixed reality applications to select out-of-reach virtual objects. However, fast hand movements can cause the visual representation of the ray to move quickly across the visual field, leading to motion artefacts that cause multiple copies of the ray to appear in discrete locations. In this work, we conduct a user study to investigate whether the conditions for motion artefact occurrence arise during a selection task that participants undertake with a pointing ray. We analyse the recorded gaze and ray movement data from the study to show that pointing actions create the conditions necessary for motion artefacts to appear. In addition, we propose a motion blur effect that we apply to the pointing ray with the aim of mitigating motion artefacts. The blur effect is evaluated in the aforementioned user study and is found to improve the perceived smoothness of ray selection, without affecting selection performance.