“…Head-gaze interaction is one of the most common approaches, which has been widely studied for target selection (e.g., [2,11,17,21]) and text entry (e.g., [35,37,41]) in VR/AR HMD. As head movements can be performed accurately yet effectively, head-gaze interaction has been used as a standalone approach and combined with or supported by other modalities, such as eyebased interaction [2,11,15,21,26,27,35]. Head-gaze has also been used, for example, to interact in games [1], map interfaces [8], and to construct new interaction methods [6,26,27,38].…”