Virtualising an Ottoman Fortress – Laser Scanning and 3d Modelling for the Development of an Interactive, Immersive Virtual Reality Application

Abstract

<p><strong>Abstract.</strong> “A picture is worth a thousand words”: a famous quote about knowledge dissemination but also literally true. The documentation of cultural heritage (CH) monuments is carried out by measurements and photos and stored in 3d models – not by textual information alone. So what could be a more straightforward way to inform the public about CH than visual information? This approach can be extended not only by providing static images or videos from predefined angles but by giving the user the opportunity to interactively explore the virtual representation and interact with the scene. Recent advances in contemporary Virtual Reality (VR) have made it available to more people as prices have dropped. New devices have entered the market so that VR is not limited to VR labs, but is available even at home. With modern head-mounted displays the user can immerse himself in the virtual CH monument to explore and interact with it. Game engines offer tools for rapid development of interactions and help to produce visually appealing worlds.</p><p>In this paper is presented the generation of a virtual 3D model of Rumeli Hisarı, an Ottoman fortress at the Bosporus in Istanbul, Turkey (Fig. 1) and its processing for data integration into the game engine Unity. The project has been carried out as a co-operation between BİMTAŞ, a company of the Greater Municipality of Istanbul, Turkey and the Photogrammetry & Laser Scanning Lab of the HafenCity University Hamburg, Germany with the aim of a VR application for an immersive and interactive visualisation of the fortress using the VR system HTC Vive. The workflow from data acquisition to VR visualisation, including the necessary programming for navigation, is described. Furthermore, the possible use (including simultaneous multiple users environments) of such a VR visualisation for a CH monument is discussed.</p>

Interactive Geo-Information in Virtual Reality – Observations and Future Challenges

“…The HTC Vive system, in its different versions, has been extensively used in geo-information research literature, especially for cultural heritage work (e.g. Kersten et al, 2018a;Kersten et al, 2018b;Tschirschwitz et al, 2019a;Tschirschwitz et al, 2019b). Exploring more mobile systems, such as the Windows Mixed Reality, that are compatible with the same content production workflows (in this case, the Unreal Engine), is highly topical for increasing the mobility of VR applications.…”

“…The mentioned polygon counts are vastly higher than those reported in game engine or other real-time rendered applications, e.g. 0.9M polygons in Kersten et al, (2018a); 0.7M in Tschirschwitz et al, (2019a) and 0.5M in final application produced in Julin et al, (2019). The challenge in applying photogrammetric or laser scanning data for game engines is in producing textured mesh models whilst maintaining sufficiently low data volumes.…”

Virtual Museums as a Means for Promotion and Enhancement of Cultural Heritage

“…Many projects are focused on the digitalization of a cultural site (Remondino et al, 2018) and its virtual exploration in an immersive way (Dhanda et al 2019;Choromariski et al 2019, making it possible, in some cases, the accessibility to people with disabilities (Pèrez et al, 2019). Other experimentations are aimed at the digital preservation of heritage sites at risk; in this way, the VM constitutes an educational product and an alternative way for visiting the site, relieving human pressure (Aiello et al, 2019;Tschirschwitz et al, 2019). Another interesting development is the possibility of allow the combination of exhibits physically distant from each other, or the exhibition of objects that have no physical presence and are born digital (Kazanis et al, 2017).…”

A 4D information system for the exploration of multitemporal images and maps using photogrammetry, web technologies and VR/AR

“…2) can be seen as everything between the two extrema, completely real environment, and completely virtual environment (Milgram et al, 1995;Styliani et al, 2009). Some recent examples are a VR application of an Ottoman fortress (Tschirschwitz et al, 2019), research concerning the effectiveness of the AR application in Augusta Raurica (Armingeon, Komani, Zanwar, Korkut, & Dornberger, 2019), or the MR application of the reconstruction of one building of the Bergen-Belsen concentration camp (Oliva et al, 2015).…”