Action-Based Undo: A Novel Undo System in Physics-Based 3D Virtual Environment

With the advancement of VR technology, the demand for highly immersive virtual environments has increased, driving VR adoption across various fields. This has led to growing interest in physics-based 3D virtual environments, where real-world physical principles are incorporated. In virtual environments, undo functionality allows users to quickly recover from unintended errors. While conventional 2D undo mechanisms remain applicable in non-physics-based 3D virtual spaces, they are less effective in realistic physics-based 3D virtual environments, where objects are influenced by physical forces such as gravity and friction, leading to unintended cascading interactions among multiple objects. To address this challenge, this study proposes Action-based Undo, a novel 3D undo mechanism, designed to effectively restore cascading interactions. A user study with 24 participants, compared three conditions: Action-based Undo, Object-based Undo (a conventional 2D-like approach), and No Undo using a domino task in a physics-based 3D virtual environment. Experimental results showed that Action-based Undo required the fewest interactions and the shortest recovery time, demonstrating superior task efficiency. Usability evaluations indicated positive user responses when a 3D undo function was available, particularly for Action-based Undo and Object-based Undo. The proposed Action-based Undo mechanism provides an effective solution for enhancing efficiency and usability in physics-based 3D virtual environments where frequent cascading interactions occur.