Design and Evaluation of Controller-Based Raycasting Methods for Efficient Alphanumeric and Special Character Entry in Virtual Reality

Alphanumeric and special characters are essential during text entry. Text entry in virtual reality (VR) is usually performed on a virtual Qwerty keyboard to minimize the need to learn new layouts. As such, entering capitals, symbols, and numbers in VR is often a direct migration from a physical/touchscreen Qwerty keyboard—that is, using the mode-switching keys to switch between different types of characters and symbols. However, there are inherent differences between a keyboard in VR and a physical/touchscreen keyboard, and as such, a direct adaptation of mode-switching via switch keys may not be suitable for VR. The high flexibility afforded by VR opens up more possibilities for entering alphanumeric and special characters using the Qwerty layout. In this work, we designed two controller-based raycasting text entry methods for alphanumeric and special characters input (
Layer-ButtonSwitch
and
Key-ButtonSwitch
) and compared them with two other methods (
Standard Qwerty Keyboard
and
Layer-PointSwitch
) that were derived from physical and soft Qwerty keyboards. We explored the performance and user preference of these four methods via two user studies (one short-term and one prolonged use), where participants were instructed to input text containing alphanumeric and special characters. Our results show that
Layer-ButtonSwitch
led to the highest statistically significant performance, followed by
Key-ButtonSwitch
and
Standard Qwerty Keyboard
, while
Layer-PointSwitch
had the slowest speed. With continuous practice, participants’ performance using
Key-ButtonSwitch
reached that of
Layer-ButtonSwitch
. Further, the results show that the key-level layout used in
Key-ButtonSwitch
led users to parallel mode switching and character input operations because this layout showed all characters on one layer. We distill three recommendations from the results that can help guide the design of text entry techniques for alphanumeric and special characters in VR.