A Subjective and Behavioral Assessment of Affordances in Virtual Architectural Walkthroughs

Immersive technologies, such as VR, offer first-person experiences using depth perception and spatial awareness that elucidate a sense of space impossible with traditional visualization techniques. This paper looks beyond the visual aspects and towards understanding the experiential aspects of two popular uses of VR in 3D architectural visualization: a “passive walkthrough” and an “interactive walkthrough.” We designed a within-subject experiment to measure the user-perceived quality for both experiences. All participants (N = 34) were exposed to both scenarios and afterwards responded to a post-experience questionnaire; meanwhile, their physical activity and simple active behaviors were also recorded. Results indicate that while the fully immersive-interactive experience rendered a heightened sense of presence in users, overt behaviors (movement and gesture) did not change for users. We discuss the potential use of subjective assessments and user behavior analysis to understand user-perceived experiential quality inside virtual environments, which should be useful in building taxonomies and designing affordances that best fit these environments.

Serious Gaming for Virtual Archaeoastronomy

Many cultures worldwide have left traces of sacred architecture and monuments which often show correlation to astronomical events like solstitial sunrises. Virtual archaeology can be used to explore such orientation patterns using digital reconstructions and positions of celestial objects computed from modern astronomical models. Most 3D editing systems used to build virtual reconstructions of such monuments however fail to provide astronomically accurate solar illumination models which can recreate the slightly different solar positions of antiquity or even prehistory, and even worse, any usable representation of the night sky. In recent years, two systems created independently by the authors of this study have been utilized for investigations into the orientation of architecture with respect to celestial processes. Both had their advantages and shortcomings compared to each other. One extended a dedicated open-source desktop astronomy program with a 3D rendering engine where such monuments can be investigated in the first-person perspective by interactive walkthrough. The other system uses a game engine and external online resources which provides only solar or planetary positions, but no star data. This study presents ways of connecting both systems in an attempt to take advantage of the best of both approaches.

Parallel Rendering Strategies for 3D Emulational Scene of Live Working

Because of abundant deep scene nodes in 3D emulational scene of live working, the existing three-dimensional scene data organization methods and rendering strategies have many flaws, such as the jumping of rendering and the delay of interactive response. A real-time rendering method for huge amount of urban data was presented utilizing the techniques such as identifying model that is based on multi-grid block partition, thread pool, caching and real time external memory scheduling algorithms. The whole scene was partitioned into blocks of different size and the blocks were arranged with multi-grid which is related to model ID and tile ID to accelerate model scheduling. Fast clipping was achieved through the nailing of position and direction of block-based view frustum, and touching task of data downloading off into thread pool executed in background which achieve the dynamic data loading and parallelism of three-dimensional scene rendering. To solve the choke point at computer hardware, in-out memory scheduling algorithms are adopted to eliminate invisible scene models and recycle dirty data in memory. Experimental results showed that the method is very efficient and suitable for applications in massive urban models rendering and interactive walkthrough.