COMPARISON OF CHARACTERISTICS OF BIM VISUALIZATION AND INTERACTIVE APPLICATION BASED ON WEBGL AND GAME ENGINE

How can we make the building information model accessible to all stakeholders on a project? An efficient approach is to access the building information model is to use the software that created the model. However, not all stakeholders will be able to use this highly specialized software—due to lack of training and expensive licences—even if some software specially developed a simplified version of the viewer to browse the model, however, it still failed to provide convenient access to these models for participants from a wide range of backgrounds. The current development of BIM model visualization and interactive applications is mainly based on two technologies: WebGL and game engines. What is the general workflow of WebGL and Game Engines supporting application development? What are their characteristics respectively? What conditions are restricted? There are no relevant academic papers to discuss and compare these two types of platforms. Therefore, this is the content of this essay. By comparing the workflow and characteristics of BIM visualization and interactive application development based on WebGL and Game Engine, it can provide a reference for heritage building managers when planning the development of relevant application tools and meet the participation needs of different stakeholders

Auditing an urban park deck with 3D geovisualization—A comparison of in-situ and VR walk-along interviews

Virtual reality-based urban audit methods are gaining increasing attention; however, most virtual urban audit studies have focused on panoramic views. The 3D city model-based geovisualizations have remained until now rather unexplored in user studies for urban audits and for communicative urban planning. We explored the feasibility of a 3D geovisualization-based urban audit in virtual reality (VR) for assessing the perceived quality of an urban park deck in Helsinki, Finland. For this purpose, we created a photorealistic and geometrically accurate 3D model (Bryga 3D) based on photogrammetric and laser scanning data. Bryga 3D was implemented on a game engine to be viewed with a head-mounted VR display. Bryga 3D's ability to convey information in a subjective urban audit, that is, subjectively perceived affordances of a park deck, was tested in a walk-along interview study comparing auditing in situ and via the VR method. A comparison of the results with in-situ (n = 13) and VR interviews (n = 21) show that the perception of several tangible elements, such as spatial division, landforms, paths, and chairs when using Bryga VR was similar to when performed in situ. Perception of vegetation was weaker in VR in terms of its detailed quality, which somewhat affected the presented development ideas and assessment of the seasonal context. Also, weaker perception of the surroundings and city context affected the results in VR. However, considering that Bryga 3D presents an example of a highly automated 3D city modeling process conducted with minimal manual work, its results are encouraging for future attempts to advance such realizations for the purposes of communicative urban planning. 3D geovisualization-based virtual audits could be used when urban green space audits are not possible or when they are demanding to implement in situ.</p

Sense of presence and sense of place in perceiving a 3D geovisualization for communication in urban planning – Differences introduced by prior familiarity with the place

Technological development towards increased visual quality and accessibility has made photorealistic 3D geovisualizations an interesting tool for communication in urban planning. Particularly the ability to support perception is important in assessing 3D geovisualizations’ effectiveness for communication. We applied both the concept of sense of presence, i.e. effectiveness of the medium, and sense of place, i.e. meanings and affordances, in a user study conducted through a web-based 3D geovisualization. The study addressed a shopping mall in Helsinki, Finland. We collected a sample of adolescent respondents (n = 122), both familiar and unfamiliar with the geovisualized place in question. Adolescents responded to a survey addressing their perceptions of the mall after the virtual visit. The results indicate that prior familiarity with the place affects the results with the sense of presence, sense of place and preferred urban planning outcome. Familiar respondents were more likely to prefer preservation of the mall. The results show how sense of presence and sense of place work in interplay in the perception of a photorealistic 3D geovisualization. Perception is not only dependent on the realism the 3D geovisualization is able to transmit but also on the individual knowledge and experiences of the audience. According to the results, 3D geovisualizations are best used as supportive tools in communication for urban planning and secondary to a real visit.</p

3D Measuring and modelling processes in gamifying culture with extended reality

Tässä tutkimuksessa selvitetään 3D-mittaus- ja -mallinnusprosessit, joilla erilaisista kulttuurin alan kohteista voi muodostaa automaattisesti tai puoliautomaattisesti pelimoottoriin soveltuvia 3D-malleja. Mallin kriteereiksi asetettiin soveltuvuus pelimoottorilla tehtävään visualisointiin ja pelillistämiseen laajennetun todellisuuden avulla. Työssä osallistuttiin osana tutkimusryhmää kolmeen erilaiseen esimerkkitapaukseen, joiden pohjalta soveltuvat prosessit johdettiin. Esimerkkitapausten kohteina olivat Dipoli, Kansallismuseon esineet ja Suomenlinnan vankityrmät. Mittausmenetelminä hyödynnettiin laserkeilausta, fotogrammetriaa ja syvyyskamerapohjaista mittausta. Kirjallisuuskatsauksessa tarkastellaan 3D-mittauksen ja -mallinnuksen sekä pelillistämisen ja peliteknologian hyödyntämisen nykytilaa. Lisäksi esitellään erilaisia kulttuurin alan sovelluksia sekä nykyaikaisten mittaus- ja mallinnusprosessien kulkua. Työn tuloksena syntyi menetelmäkohtaiset prosessikuvaukset pelimoottorikelpoisen 3D-mallin tuottamiseksi. Prosessikuvausten pohjalta pohdittiin menetelmien soveltuvuutta, toimintaa ja rajoituksia sekä vertailtiin tuloksia tutkimuskirjallisuuteen. Lisäksi tehtiin katsaus tulevaisuuden mahdollisuuksiin ja niiden vaikutuksiin esimerkkitapausten kannalta.This study investigates the 3D measurement and modeling processes needed to automatically or semi-automatically create 3D models from a variety of cultural attractions for use in game engines. The criteria for the model were suitability for game engine visualization and gamification through augmented reality. Suitable processes were derived from three different case studies by taking part in them. The case studies used, were Dipoli, objects from National museum and the jail cells of Suomenlinna. Laser scanning, photogrammetry and depth camera technology were used as the measurement methods. The literature review gives an overview of the current state of 3D measurement and modeling as well as gamification and game technology utilization. In addition, various cultural 3D applications and the phases of modern measurement and modeling processes will be introduced. The work resulted in method specific process descriptions to produce a game engine suitable 3D model. Based on the process descriptions, the applicability, functionality and limitations of the methods were discussed, and the results compared to the research literature. In addition, a review was made of future opportunities and their implications for case studies

Impact of Imaging and Distance Perception in VR Immersive Visual Experience

Virtual reality (VR) headsets have evolved to include unprecedented viewing quality. Meanwhile, they have become lightweight, wireless, and low-cost, which has opened to new applications and a much wider audience. VR headsets can now provide users with greater understanding of events and accuracy of observation, making decision-making faster and more effective. However, the spread of immersive technologies has shown a slow take-up, with the adoption of virtual reality limited to a few applications, typically related to entertainment. This reluctance appears to be due to the often-necessary change of operating paradigm and some scepticism towards the "VR advantage". The need therefore arises to evaluate the contribution that a VR system can make to user performance, for example to monitoring and decision-making. This will help system designers understand when immersive technologies can be proposed to replace or complement standard display systems such as a desktop monitor. In parallel to the VR headsets evolution there has been that of 360 cameras, which are now capable to instantly acquire photographs and videos in stereoscopic 3D (S3D) modality, with very high resolutions. 360° images are innately suited to VR headsets, where the captured view can be observed and explored through the natural rotation of the head. Acquired views can even be experienced and navigated from the inside as they are captured. The combination of omnidirectional images and VR headsets has opened to a new way of creating immersive visual representations. We call it: photo-based VR. This represents a new methodology that combines traditional model-based rendering with high-quality omnidirectional texture-mapping. Photo-based VR is particularly suitable for applications related to remote visits and realistic scene reconstruction, useful for monitoring and surveillance systems, control panels and operator training. The presented PhD study investigates the potential of photo-based VR representations. It starts by evaluating the role of immersion and user’s performance in today's graphical visual experience, to then use it as a reference to develop and evaluate new photo-based VR solutions. With the current literature on photo-based VR experience and associated user performance being very limited, this study builds new knowledge from the proposed assessments. We conduct five user studies on a few representative applications examining how visual representations can be affected by system factors (camera and display related) and how it can influence human factors (such as realism, presence, and emotions). Particular attention is paid to realistic depth perception, to support which we develop target solutions for photo-based VR. They are intended to provide users with a correct perception of space dimension and objects size. We call it: true-dimensional visualization. The presented work contributes to unexplored fields including photo-based VR and true-dimensional visualization, offering immersive system designers a thorough comprehension of the benefits, potential, and type of applications in which these new methods can make the difference. This thesis manuscript and its findings have been partly presented in scientific publications. In particular, five conference papers on Springer and the IEEE symposia, [1], [2], [3], [4], [5], and one journal article in an IEEE periodical [6], have been published

Automated Multi-Sensor 3D Reconstruction for the Web

The Internet has become a major dissemination and sharing platform for 3D content. The utilization of 3D measurement methods can drastically increase the production efficiency of 3D content in an increasing number of use cases where 3D documentation of real-life objects or environments is required. We demonstrated a developed, highly automated and integrated content creation process of providing reality-based photorealistic 3D models for the web. Close-range photogrammetry, terrestrial laser scanning (TLS) and their combination are compared using available state-of-the-art tools in a real-life project setting with real-life limitations. Integrating photogrammetry and TLS is a good compromise for both geometric and texture quality. Compared to approaches using only photogrammetry or TLS, it is slower and more resource-heavy but combines complementary advantages of each method, such as direct scale determination from TLS or superior image quality typically used in photogrammetry. The integration is not only beneficial, but clearly productionally possible using available state-of-the-art tools that have become increasingly available also for non-expert users. Despite the high degree of automation, some manual editing steps are still required in practice to achieve satisfactory results in terms of adequate visual quality. This is mainly due to the current limitations of WebGL technology