3D As-Built Environments in Extended Reality Applications: A Systematic Review

Accurate integration and navigation of real-world 3D spaces are fundamental for next-generation Extended Reality (XR) systems, enhancing immersion, utility, and fidelity. This paper systematically reviews XR workflows using PRISMA guidelines, focusing on 3D data acquisition, modeling, visualization, and user interaction, based on 96 journal publications. Data collection for XR relies on photogrammetry, RGB-D cameras, and LiDAR, often enhanced by multi-sensor fusion, although real-time transmission and semantic alignment remain challenging. XR pipelines are dominated by Building Information Modeling (BIM) software and game engines, frequently integrating Computer-Aided Design (CAD) models and 3D scanned data. Visualization varies from photorealistic renderings to schematic representations, with Virtual Reality headsets favored for training and Augmented Reality devices applied in inspection and navigation. Interaction paradigms encompass controllers, gestures, gaze, voice, and haptics, with increasing reliance on Artificial Intelligence for multimodal fusion and processing. Despite progress, key challenges persist, including bandwidth limitations, manual 3D modeling, hybrid data management, interoperability issues, and scarcity of open-source solutions. Additional identified barriers involve balancing visual quality with performance in specific contexts, limited accuracy of non-invasive Brain-Computer Interfaces, and restricted market acceptance due to high costs. Overall, XR adoption remains constrained by technical, usability, and accessibility gaps.