User experience of architectural detailing in virtual urban environment

Architecture and urban design disciplines very much adhere to the use of representations as a tool to aid decision making process. As it is almost impossible to replicate environments in full-scale, both physical and digital representations are therefore restricted by the notions of scale and level of details. These notions are now challenged by the emergence of virtual reality (VR) technology, which allows architects to work with full-scale virtual environments (VEs). However, the taxonomy of architectural representations in VR is not properly defined as discussions in academia are mostly concerned about creating realistic impressions of space, rather than the operational side of different architectural detailing. Thus, in recognizing the operational dimensions of VEs in VR, it is vital to examine the influence of different architectural detailing on the legibility of VEs. This study aimed to suggest a guideline for users’ experience of architectural detailing in a VE for a large-scale urban simulation. This study was executed as an experimental simulation study. In a total of N=96 respondents were divided into four different treatments with n=24 respondents in each VE with a unique level of architectural detailing. They answered the questionnaire surveys and drew cognitive maps after completed navigating within the VEs using VR. Analysis methods used were primarily of content analysis, Kruskal-Wallis H test, and one-way ANOVA. The first analysis phase was environment-specific and the second phase was route and point-specific. In the third phase, the findings from previous phases were triangulated. The most and the least legible VEs were established as per different abilities of interpreting VEs. The operational dimensions of the VEs were established based on the deconstructed architectural detail components namely ‘geometric extrusion’ and ‘distinction’ as the factors influencing legibility of VEs. The operational dimensions of each VE were synthesized based on various criteria derived from the abilities of interpreting VEs. Based on the statistically significant results, the criteria were reduced to ‘understanding VE’ and ‘recalling VE’, in that order. In conclusion, there are some influences of architectural detailing on legibility but only in regards to the two criteria. The operational dimensions were also established for each criterion, which was learned from the cognitive knowledge data. Firstly, is for tasks within one viewpoint. Secondly, is for linear navigation and lastly is for full-fledged virtual exploration. This thesis also proposed two main guidelines for the user experience of architectural detailing in urban VE to be used by architects and users in the associated domain

3D City Models and urban information: Current issues and perspectives

Considering sustainable development of cities implies investigating cities in a holistic way taking into account many interrelations between various urban or environmental issues. 3D city models are increasingly used in different cities and countries for an intended wide range of applications beyond mere visualization. Could these 3D City models be used to integrate urban and environmental knowledge? How could they be improved to fulfill such role? We believe that enriching the semantics of current 3D city models, would extend their functionality and usability; therefore, they could serve as integration platforms of the knowledge related to urban and environmental issues allowing a huge and significant improvement of city sustainable management and development. But which elements need to be added to 3D city models? What are the most efficient ways to realize such improvement / enrichment? How to evaluate the usability of these improved 3D city models? These were the questions tackled by the COST Action TU0801 “Semantic enrichment of 3D city models for sustainable urban development”. This book gathers various materials developed all along the four year of the Action and the significant breakthroughs

The Nigerian novel and the postcolonial city

This thesis is a critical inquiry into the nature of the postcolonial African city as represented in fiction. It examines how the Nigerian novel represents the postcolonial African city and the extent to which it confirms or contests the dominant paradigms of scholarship in urban studies. In it, perspectives from urban studies are brought into conversation with literary representations of the postcolonial African city in contemporary Nigerian fiction thereby creating a nuanced synthesis of postcolonial literary studies and urban scholarship. Its provocative argument is that the postcolonial African city is both functional and legible despite its arguably squalid state and the undesirable living conditions of its subjects. Approaches that denigrate so-called Third World cities as particularly dystopic and illegible do not present the whole picture and are therefore one-sided and misleading. The Nigerian novel, it argues, reflects the need for rethinking of the dominant templates of urban studies to take into consideration the particularities and complexities of postcolonial cities. The thesis examines representations of the postcolonial city in four recent Nigerian novels: Ben Okri's The Famished Road (1991), Okey Ndibe's Arrows of Rain (2000), Chris Abani's GraceLand (2004), and Sefi Ata's Everything Good Will Come (2006). The selected novels' analyses foreground the argument that there is no universal template for theorizing the city; hence, there is a legitimate basis for talking about the postcolonial city both in conception and fictional representation. The thesis begins with an introduction which encompasses the aim, focal question, rationale, design/structure and the definition of key terms. This is followed by Chapter One which gives an insight into the state of the research field. The chapter reviews relevant scholarship with a view to situating modernity and the postcolonial city in Africa. In Chapters Two, Three, Four and Five, the primary texts, under various subtitles, are analyzed. The novels' representation(s) of the postcolonial (African) city, from different perspectives – like the problematic of legibility and spatial morphology, infrastructure, agency, urban governmentality, etc. – are critically examined. Chapter Six examines the place of bars and gender in determining the metro poetics of the postcolonial African city and how they are depicted in the selected novels. This is followed by the Conclusion, which summarizes the thesis by restating and highlighting its major argument and the ways in which it is elaborated upon in the fictional texts analyzed in the various chapters

Legible Simplification of Textured Urban Models

Most of the algorithms used for research in mesh simplification and discrete levels of detail (LOD) work well for simplifying single objects with a large number of polygons. For a city-sized collection of simple buildings, using these traditional algorithms could mean the disappearance of an entire residential area in which the buildings tend to be smaller than those in commercial regions. To solve this problem, we developed a mesh-simplification algorithm that incorporates concepts from architecture and city planning. Specifically, we rely on the concept of urban legibility, which segments a city into paths, edges, districts, nodes, and landmarks. If we preserve these elements of legibility during the simplification process, we can maintain the city's image and create urban models that users can understand more effectively. To accomplish this goal, we divide our algorithm into five steps. During preprocessing, it performs hierarchical clustering, cluster merging, model simplification, and hierarchical texturing, at runtime, it employs LOD to select the appropriate models for rendering

The Impact of Sound on Virtual Landscape Perception: An Empirical Evaluation of Aural-Visual Interaction for 3D Visualization

An understanding of quantitative and qualitative landscape characteristics is necessary to successfully articulate intervention or change in the landscape. In landscape planning and design 3D visualizations have been used to successfully communicate various aspects of landscape to a diverse population, though they have been shown to lag behind real-world experience in perceptual experiments. There is evidence that engaging other senses can alter the perception of 3D visualizations, which this thesis used as a departure point for the research project. Three research questions guide the investigation. The first research question is: How do fundamental elements in visualizations (i.e. terrain, vegetation and built form) interact with fundamental sound types (i.e. anthropogenic, mechanical and natural) to affect perceived realism of, and preference for, 3D landscape visualization? The research used empirical methods of a controlled experiment and statistical analysis of quantitative survey responses to examine the perceptual responses to the interaction aural and visual stimuli in St. James’s Park, London, UK. The visualizations were sourced from Google Earth, and the sounds recorded in situ, with Google Earth chosen as it is being used more frequently in landscape planning and design processes, though has received very little perceptual research focus. The second research question is: Do different user characteristics interact with combined aural-visual stimuli to alter perceived realism and preferences for 3D visualization? The final research question emerged out of the experiment design concentrating on research methodology: How effective is the Internet for aural-visual data collection compared to the laboratory setting? The results of the quantitative analysis can be summarized as follows: For research question 1 the results show that sound alters 3D visualization perception both positively and negatively, which varies by landscape element. For all visual conditions mechanical sound significantly lowers preference. For visualizations showing terrain only perceived realism and preference are significantly lowered by anthropogenic sound and significantly raised by natural sound for both realism and preference. For visualizations showing a combination of terrain with built form anthropogenic and mechanical sound significantly raises perceived realism. For visualizations showing a combination of terrain, vegetation and some built form a more complicated interaction occurs for realism, which is moderated by the amount of built form in the scene, e.g. with no buildings in the scene traffic and speech significantly lower realism ratings in similar ways while a small amount of built form visible resulted in speech significantly raising realism ratings. Preference was significantly lowered by anthropogenic and mechanical sound the most out of all three visual conditions. For research question 2 the results confirm that perception can vary for realism by gender and first language differences, and preference by age, first language, cultural and professional background and 3D familiarity. Finally for research question 3 and implications for Internet-based multisensory experiments there is strong evidence that audio hardware and experimental condition (laboratory vs. online) do not significantly alter realism and preference ratings, though larger display sizes can have a significant but very small effect on preference ratings (+/- 0.08 on a 5-point scale). The results indicate that sound significantly alters the perception of realism and preference for landscape simulated via 3D visualizations, with the congruence of aural and visual stimuli having a strong impact on both perceptual responses. The results provide important empirical evidence for future research to build upon, and raise important questions relating to authenticity of landscape experience, particularly when relying solely on visual material as visuals alone do not accurately simulate landscape experience. In addition the research confirms the cross-sensory nature of perception in virtual environments. As a result the inclusion of sound for landscape visualization and aesthetic research is concluded to be of critical importance. The research results suggest that when using sound with 3D visualizations the sound content match the visualized material, and to avoid using sounds that contain human speech unless there is a very strong reason to do so (e.g. there are humans in the visualization). The final chapter discusses opportunities for integrating sound with 3D visualizations in order to increase the perception of realism and preference in landscape planning and design processes, and concludes with areas for future research

N.: Legible simplification of textured urban models

UNC Charlotte Mesh simplification and discrete levels of detail (LOD) are wellstudied areas of research in computer graphics. However, until recently, most of the developed algorithms have focused on simplification and viewing of a single object with a large number of polygons. When these algorithms are applied to a large collection of simple models, many objects may be completely erased, leading to results that are misleading to the viewer. In this paper, we present an approach to simplifying city-sized collections of 2.5D buildings based on the principles of “urban legibility ” as defined by architects and city planners. We demonstrate that our method, although similar to traditional simplification methods when compared quantitatively, better preserves the legibility and understandability of

Cognitive Foundations for Visual Analytics

In this report, we provide an overview of scientific/technical literature on information visualization and VA. Topics discussed include an update and overview of the extensive literature search conducted for this study, the nature and purpose of the field, major research thrusts, and scientific foundations. We review methodologies for evaluating and measuring the impact of VA technologies as well as taxonomies that have been proposed for various purposes to support the VA community. A cognitive science perspective underlies each of these discussions