Zsolt Buna’s research while affiliated with Technical University of Cluj-Napoca and other places

The most peculiar characteristic of a cultural heritage is represented by its uniqueness. To ensure that an object is preserved against environmental deterioration, vandal attacks, and accidents, modern Cultural Heritage documentation involves 3D scanning technologies. In the case of fragmented artefacts, the digitization process represents an essential prerequisite for facilitating an accurate 3D reconstruction. The aim of this research paper is to present a framework that enables an accurate digital reconstruction of fragmented or damaged artefacts using ornament stencils obtained from 3D scan data. The proposed framework has been applied for the richly adorned ornaments of the fragmented Dacian embossed disk from Piatra Roșie. The case study makes use of the 3D dataset acquired, using a structured light scanner to extract vector displacement maps, which are then applied to the 3D computer-aided design (CAD) model. The output of the framework includes a proposed digital reconstruction of the aurochs fragmented Dacian embossed disk, as well as the ornaments’ stencils database. The proposed framework addresses problems that are associated with 3D reconstruction processes, such as self-intersections, non-manifold geometry, 3D model topology, and file format interoperability. Finally, the resulting 3D reconstruction has been integrated within virtual reality (VR), augmented reality (AR), and mixed reality (MR) applications, as well as computer-aided manufacturing (CAM) based on additive manufacturing to facilitate the dissemination of the results.

Wooden Churches from Romania represent the tangible part of the Christian tradition identity and wood crafting mastery from rural villages. Until the beginning of the 20th century, the Romanians created and manifested themselves mainly in a civilization of wood, of a richness, a variety, and a remarkable refinement, in which the wooden churches reached their maximum peak of expression. In Romania there are over 1400 wooden churches built before 1918. The wooden churches represent an invaluable asset for the Romanian culture. Many of the wooden churches require conservation and restoration interventions to ensure their long-term preservation. The wooden church from Cizer represents the case study presented within this article, which was transferred to the Romulus Vuia National Ethnographic Park within Cluj-Napoca in the year 1968 and which was restored and reopened to the visitors along with the wooden church from Petrindu within a project financed by the SEE 2009-2014 Financial Mechanism. The article presents the workflow that made use of 3D scanning and virtual reality technologies to promote and capitalize on the invaluable wooden church from Cizer, which is one of the most representative, wooden churches from Transylvania. The results of the research work are aimed to provide a detailed * This work was realized within the project "Horea`s Church-a heritage for the future. Capitalizing on an 18th century architectural monument through virtual reality" (Unique project code CALL01-16), funded with the support of the EEA Grants 2014-2021 within the RO-CULTURE Programme. 10 Radu Comes, Călin Neamțu, Zsolt Buna, Ștefan Bodi, Cătălin Grec, Daniel Costea digital conservation that has been integrated within an immersive virtual reality environment, thus allowing visitors to transpose within the church. Various cultural heritage assets linked to the Cizer wooden church have been 3D scanned and added to the virtual reality environment to enhance visitors' experience.

Recent advancement in digital technologies enabled the development of innovative and interactive museum exhibitions. These emerging technologies can be used to define unprecedented interactive experiences within museum exhibitions allowing users to interact with accurate digital replicas of the cultural heritage assets displayed within the real museum. Some of the 3D scanned glass icon paintings had missing or deteriorated areas. The authors have proposed a virtual restoration technique aimed to digitally recreate the original appearance of the icons on glass. The digitally restored icons have been added to the virtual reality environment along with the original icons, allowing users to visualize them at the same time and interact with them. The innovative digital technologies that integrate natural gesture sensors and virtual reality systems with force feedback input enables users to interact naturally with the digital replicas, therefore providing a creative and entertaining environment. This research article main goal is to present the development and implementation of the innovative digital technologies within the Ethnographical Museum of Transylvania regarding the glass painting icons from the Sebeș Valley collection. * This work was realized within the project project "Innovative techniques in capitalizing on cultural heritage. The icons from the Sebeș Valley from the collection of the Ethnographic Museum of Transylvania" (Unique project code CALL01-15), funded with the support of the EEA Grants 2014-2021 within the RO-CULTURE Programme.

The wooden churches from Transylvania, Romania, are a unique and representative cultural heritage asset for rural communities, both in terms of architecture and the style of painting that defines them as monuments of national heritage. These churches are in danger of degradation because rural communities are beginning to abandon them for various motives (e.g., they are too small, are expensive to maintain, or are being replaced by modern churches, built of stone and modern materials). The reason behind their accelerated degradation is that they are covered with shingles that need to be periodically changed and repaired to prevent water from reaching the inner painting layer, a process that is, in many cases, ignored. Imperial gates are the symbol of these churches and separate the nave from the narthex. They are made entirely out of wood and were sculpted and painted manually by skilled craftsmen and still represent the central element of these churches, in terms of art and aesthetics. The digital preservation of these heritage assets is an interdisciplinary undertaking, which begins with the physico-chemical analysis of the pigments in the painting layer, continues with three-dimensional (3D) digitization of the monument and of the objects of interest (such as the imperial gates), and finishes with a digital restoration of these monuments and artefacts. This paper presents a working methodology, successfully applied in digitizing and digitally restoring imperial gates from wooden churches in Transylvania, namely from the wooden church of Voivodeni, Sălaj County, Romania (Transylvania region). X-ray fluorescence and FTIR spectroscopy were used to determine the pigments in the painting layer of these artefacts, and after they were identified, they were synthesized in laboratory conditions. The resulting color was digitized and used for digitally restoring the artefact(s) to its (their) pristine condition. To popularize these cultural heritage assets, the authors make use of virtual reality to mediate the interaction between the general public and heritage objects in their current state of preservation, in a digital environment. Moreover, to showcase how these heritage objects were degraded over time, a digitally restored version of the artefact in pristine condition is presented alongside a version in its current state (as is, digitized, but not yet digitally restored).

The process of documenting cultural heritage digitally has emerged with the recent technological developments. One of the direct consequences of using digital devices to promote cultural heritage is to educate the end-users and to exceed their initial expectations regarding their interaction and engagement with cultural heritage assets. Creativity is encour-aged and stimulated by technology; as a result, cultural heritage domain must use technologies and tools from various domains such as engineering (3D scanning), gaming industry (VR headsets), digital marketing (interactive screens) to create interactive exhibitions. These tools can be paired with classical cultural heritage exhibition methods to attract, engage and support end-users more efficiently and effectively by creating unprecedented interactive. For this endeavor more than 560 artifacts have been digitized, the monuments and the fortress have been digitally reconstructed and integrated in digital applications that were combined with classical museum exhibition methods. By doing so, the paper also brings contributions concerning the methodologies used for deploying state of the art scanning and digitizing technologies. The main motivation was to bring classic exhibition techniques to modern times and to attract the young audiences to museums, thus identifying how they can be more engaged, involved and educated within the mixed museum spaces.

Sarmizegetusa Regia was included, together with the other five Dacian fortresses, on the List of UNESCO World Heritage Sites in 1999. They are a unique synthesis of external cultural influences and local traditions in terms of building techniques and overall, in the ancient military architecture, representing the grand expression of the civilisation of the Dacian Kingdom. These fortresses are the accurate expression of the exceptional development level of the Dacian civilisation, Sarmizegetusa Regia lying at the forefront of this fortified complex, epitomizing the evolution phenomenon from fortified centres to proto-urban agglomerations. As such, promoting these monuments and the numerous artefacts discovered by modern methods and techniques should become a priority. This paper presents a series of last generation applications and equipment that may be successfully used in promoting cultural heritage. Case studies include scanned artefacts and 3D reconstructions of the monuments in the site of Sarmizegetusa Regia, a monument on the UNESCO List of World Heritage Sites together with the other five Dacian fortresses (Bănița, Costești-Blidaru, Costești-Cetățuie, Piatra Roșie and Căpâlna). We present here the results obtained following the use of several hardware tracking systems, augmented virtual reality applications and haptic devices. One of the important aspects, when attempting to make enhanced on-line use of heritage good is the extent to which it is accessible and reusable by various categories of users, either specialists or the general public. Digitalizing a good in the cultural heritage is the first step for ensuring the broad access via the on-line medium, the quality of this process ensuring the electronic format artefact legitimacy and credibility, which means that it should be an electronic duplicate truthful to the real artefact. This way, they may be digitally preserved and used in various manners. Digitalizing artefacts and the digital reconstruction of houses, appurtenances, workshops, temples and fortifications and the setup of virtual tours ensure incursions in the daily life as resulting from the archaeological finds yielded over several decades. This process results in quick promoting of this cultural heritage and its international capitalizing. All this completed by a database in the form of an open web platform to manage the 3D models, which may be later completed by other scanned 3D models, is the way to proceed for as many as possible monuments and artefacts.

This paper is focused on highlighting the advantages of using modern augmented reality applications to support the widespread dissemination of Cultural Heritage assets. This kind of applications have the potential to improve the user experience when they are visualizing a hard cover printed book or catalogue. The main advantage of this solution is to allow users to use their personal smartphones and tablets to access additional interactive content related to main subject of tangible books. Using the proposed solution described within the article any printed material can become interactive using multimedia elements such as: audio files, 3D models, images, videos (2D,3D, 360°), 3D text or any other form of digital content. The application adds multimedia information on top of the printed information increasing the degree of understanding of the information presented in the form of a book / catalogue, regardless of the time in which it was written and published.

The paper presents a new approach for the virtual reconstruction of historical artifacts such as ceramic pots. The technique is based on the photogrammetry method through which the profile line of the pot is achieved and which is composed by a fixed number of inflection points. The parameterization of the profile is then followed by the creation of a macro (script) in CAD software in order to automatically generate the shape of the ceramic pot. The case study included in the article consists of a total of 15 families of ancient ceramic pottery. The purpose of this technique is to serve as a support both for historians, archaeologists and restorers, as well as for students who desire a fast, fair and accessible virtual reconstruction of ceramic pots, regardless of their considered knowledge in designing or editing a programming language.