Comparing Physics-based Hand Interaction in Virtual Reality: Custom Soft Body Simulation vs. Off-the-Shelf Integrated Solution

Physics-based hand interaction in VR has been extensively explored, but almost none of the solutions are usable. The only exception is CLAP, a custom soft body simulation offering realistic and smooth hand interaction in VR. Even CLAP, however, imposes constraints on virtual hand and object behavior. We introduce HPTK+, a software solution that utilizes the physics engine NVIDIA PhysX. Benefiting from the engine's maturity and integration with game engines, we aim to enable more general and free-hand interactions in virtual environments. We conducted a user study with 27 participants comparing the interactions supported by both libraries. Results indicate an overall preference for CLAP, but no significant differences in other measures or performance, except variance. These findings provide insights into the libraries' suitability for specific tasks. Additionally, we highlight HPTK+'s exclusive support for diverse interactions, positioning it as an ideal candidate for further research in physics-based VR interactions.