3D Digital Reconstructions of Lost Buildings

A first critical framing

Danilo Di Mascio1, Michele Chiuini2, John Fillwalk3, Pieter Pauwels4 1Northumbria University 2,3Ball State University 4Ghent University [email protected] 2,3{mchiuini|jfillwalk}@bsu.edu [email protected]

This paper presents a first critical framing of 3D digital reconstructions of lost buildings, hence focusing on reconstructions using 3D models. This critical framing is constituted by reflections on definitions, concepts, methodologies and digital technologies. Much experimentation in the digital reconstruction of lost buildings has produced valuable results during the last twenty years, but the variety of methods, software types, and purposes should be reorganized into clear operational protocols to allow sharing of information and collaboration across disciplines. We have therefore investigated the diverse approaches towards digital reconstructions of lost buildings and found that digital reconstructions are not typically aimed at simple visualizations: they are often further developed in virtual environments, information systems and tools for simulations and analysis. In this sense they are not products but instruments for further research and/or heritage conservation. Counter the large number of theoretical positions, methods and tools specific to different disciplines, such as architecture and archaeology, we can find the almost total absence of a comprehensive critical assessment. This paper, which is part of a larger project, intends to open and articulate a debate on how to define, analyze and critically systematize the methodologies for the digital reconstruction of lost buildings.

Keywords: Digital reconstruction, lost buildings, 3d modelling, information systems, virtual environments.

INTRODUCING 3D DIGITAL RECONSTRUC- select key aspects of previous projects about digital TIONS OF LOST BUILDINGS: WHAT, WHY reconstructions of lost buildings. References (con- AND HOW ference papers, journal articles, books and websites) An analysis of several sources, supported by authors' have been checked from areas of intersections be- experiences in this field, have allowed to identify and tween digital technologies with architecture and ar- chaeology. Moreover, websites of specific research

DIGITAL HERITAGE - Volume 2 - eCAADe 34 | 511 projects have also been consulted. This preliminary gies of buildings and historical periods, such as lost study has made evident the variety of characteristics palaces [3]. This research deals with virtual recon- of this research field. Lost buildings and their forgot- structions of historical, courtly architecture from me- ten stories have always attracted the cultural inter- dieval and early modern periods. Other studies (An- ests and curiosity of scholars and lay people world- derson et al., 2009) focus on specific technologies wide. An early example in which 3D modeling soft- (in this case game technologies applied to serious ware is applied for lost buildings can be found in games) in a chosen field, cultural heritage. However, the Old Minster in Winchester, UK [1]. A long list of the piece of writing describes serious games in cul- similar research initiatives have applied 3D model- tural heritage, whereas we aim to focus on technolo- ing and virtual reconstructions to a wide variety of gies applied to lost building in general.We propose no longer existing buildings and cities from the me- here to organize the digital reconstruction process by dieval church of Cluny III, to Dudley Castle and the replying to three main questions: what, why and how ancient Rome [2]. A digital reconstruction process of (Figure 1). These three questions define the main as- lost buildings is constituted by several aspects and pects of digital reconstructions of lost buildings and steps; hence the main question is related to how to at the same time can be used to build up a first crit- critically systematize this variety of heterogeneous ical frame for research. Next sections will elaborate information. As far as we know, this work repre- each of these three questions, respectively (defini- sents the first such critical framing that tries to con- tion and analysis), whereas the concluding sections sider 3D digital reconstructions of lost buildings in a build up the targeted frame for the digital reconstruc- more comprehensive way. Most of the previous pub- tion of lost buildings (discussion and conclusion re- lications are focused on the description of individ- spectively). ual research projects, however there are some excep- tions. One of the most relevant is the first chapter of Figure 1 the publication by Novitski (Novitski, 1998), which is The three main entirely dedicated to lost buildings. This section of questions that the book presents descriptions of several case stud- address the digital ies pertaining to various geographic locations, histor- reconstruction process of lost ical periods and building typologies, including clas- WHAT: LOST BUILDINGS buildings. sic Greek theaters, the Columbian village of Ceren, The expression "lost buildings" identifies buildings the palace of Kublai Khan and the Larkin Building de- that have lost their original form and that pertain to signed by Frank Lloyd Wright. Each project was de- one of the following three categories: partially lost, veloped by scholars and experts with different back- totally lost and transformed. The word "building" is grounds: students, archaeologists, architects, archi- here used in a wide multi-scalar way to include both tectural historians; every description includes also in- single buildings and artefacts, designed by profes- formation about the main aims, sources and names sionals and vernacular, and settlements from small of the main software packages used. Nonetheless, villages to cities. However, we are aware of other the main aim of Novitski's work is to describe a se- definitions that include, for example, unbuilt projects lection of lost architectural treasures brought back (Glancey 2015), but these buildings deserve a fu- to light thanks to modern digital technologies, es- ture specific publication. It is important to define a pecially 3D modelling, rendering and animations. classification, because for each category a different Hence, there is not the explicit objective of sys- methodology may apply. We are proposing three tematizing digital reconstructions of lost buildings. general categories that represent what kind of lost Other publications are focused on specific typolo- buildings can be modelled, namely: totally lost, par-

512 | eCAADe 34 - DIGITAL HERITAGE - Volume 2 tially lost and transformed (see Figure 2). mation system resulting from the modelling process. The main conceptual, theoretical and methodologi- Figure 2 cal approaches towards the digital reconstruction of Diagram that shows lost buildings lie within disciplines such as architec- the first phase of ture and archaeology. The methodologies of recon- the digital struction are conceptually related to the restoration reconstructions of theories and to the methods of architectural history. lost buildings, This requires any reconstruction to have a scientific namely the choice basis, using literary or visual documentation, as well of what is to be as physical evidence of the remains on site and other modelled. The surviving parts. The typical example is the recon- scheme highlights struction of archaeological remains, starting from the also two other building foundations and ruins, which can be identi- aspects that fied and dated thanks to literary documents and arte- characterize those facts found in the excavations. This example leads lost buildings: the discussion to four crucial questions that repre- reason (how they sent likewise lines of investigation: became lost) and building/ì/site type. 1. How to represent conjectural parts (missing parts) from the ones that are certain (existing remains), how to indicate the level of uncer- tainty, and how to allow testing different re- construction hypotheses; 2. How to provide information about the re- WHY: OBJECTIVES AND THEORETICAL AP- assembly of parts conserved in different PROACHES places, for instance when frescoes and sculp- It is essential to highlight that the philosophies and tures integral with the architecture, but also methodologies depend on the objectives of the re- objects of daily use, are stored in musea or construction and on the disciplinary areas involved. private collections. This situation typically For instance a digital reconstruction of a building se- occurs in archaeological projects again (the riously damaged by a recent war may be finalized to Parthenon, or Pompeii houses), but other its physical reconstruction. In this case the model- cases exist as well, for instance for the Chicago ing may be following architectural design processes, Stock Exchange; which are different from the case of a historical or ar- 3. How to document the evolution of the site chaeological analysis of a building demolished cen- over time: archaeology always uncovers turies ago. The methodological differences followed a number of layers belonging to different in the digital modeling will thus depend on objec- phases of existence (while the classic graphic tives and disciplinary areas involved, mainly architec- reconstructions show buildings frozen at a ture and archaeology, as well as on the extent of the particular time in history); building remains and its documentation. In other 4. How to link or refer the reconstruction to the words, the two fields of reconstruction methodolo- documentation that forms the scientific basis gies and digital modelling methodologies must be and the socio-cultural context of the site. This seen as separate and clearly defined, but they end is an essential question for academic research up being intricately intertwined in a building infor- work as well as, in a different form, for cultural

DIGITAL HERITAGE - Volume 2 - eCAADe 34 | 513 tourism or secondary education. of particular products that are aimed at. We have outlined seven types of products, which then result All these points cover important lines of investiga- in the diagram listed below in Figure 4. However, tion about lost buildings, especially the more tradi- these products also represent further practical appli- tional ones in archaeology and architectural history, cations of the 3D digital reconstruction that use spe- but represent only part of the studies that can be cific methodologies and software packages and as undertaken. For example, in presence of totally lost such they will be further described in the next sec- buildings, the first two questions should be formu- tion. lated in a different way, because their remaining ev- idences are the sole archive records, which can be Figure 3 more or less complete. The lines of enquiry can be fo- Diagram of the why, cused on other aspects, such as 3D digital reconstruc- namely the tion of no longer existing buildings within their urban definition of the context (Martens et al. 2010), or the study of com- purpose of the 3D plex geometries of dismantled pavilions, such as the digital one designed by Le Corbusier for the 1958 Expo Exhi- reconstruction. The bition held in Brussels (Sdegno, 2012). Moreover, in image mentions disciplines such as architecture, studies on lost build- also the “product”. ings are not limited to historical investigations. Digi- tal reconstructions can also be more design oriented such as in Di Mascio (2010). In this research the mass- ing model of the fortified center of a medieval vil- lage, destroyed by an earthquake, was digitally re- constructed using historical plan views, historical pic- tures and photos collected during onsite visits (Fig- ure 3). The digital model has been used to identify tangible and intangible memories, such as shape and size of alleys and buildings, and the perceptual as- pects on the alleys, that can inform the reconstruc- tion of the fortified center (Di Mascio, 2010). We can summarize the main objectives of digital reconstruc- tions of lost buildings under four categories: HOW: THE DIGITAL RECONSTRUCTION 1. Historical/archaeological research; PROCESS 2. Visualization and information systems for cul- As previously mentioned, the choice for a specific tural tourism; digital technology ('why') is influenced by many 3. Experiential virtual visit of totally lost sites; factors, from the conceptual and theoretical ap- 4. Documentation and analysis for conservation proaches, methods and tools within each discipline and reconstruction. such as architecture or archaeology. For this reason, it is useful to highlight the main phases that charac- From the above, we are able to extend our framework terize the digital reconstruction process and study of for digital reconstructions of lost buildings with an a lost building. We can then indicate to what extent additional decisive step, namely the why of the dig- this digital reconstruction process is realized for par- ital reconstruction, which consists of a specific over- ticular types of buildings (what) and particular pur- all purpose and a preliminary definition of a number poses (why). The following three phases are consid-

514 | eCAADe 34 - DIGITAL HERITAGE - Volume 2 ered (inspired by Pauwels and Di Mascio, 2014): Synagogues in Vienna, entirely destroyed in 1938, are example cases of this situation (Martens et al., 2002). 1. Data Collection and Analysis In this latter case, the available drawings are often re- 2. 3D Digital Reconstruction drawn in vector format, in software such as Autodesk 3. Multifaceted applications of the 3D model Autocad, to be used as reference during the 3D mod- (documentation, analysis, and enrichment) eling. 4. Dissemination 3D Digital Reconstruction Data Collection and Analysis The main objective of the 3D digital reconstruction Every digital reconstruction starts with a data collec- phase is to digitally recreate a 3D model of the con- tion phase in which the main objective is to gather in- sidered object. The whole process is influenced by formation to support the modeling process. Besides three main concerns: the collected data (and the way traditional tools (on-site measurements and data col- of collecting them) during the previous phase, the lection, both intrusive and non-intrusive), 3D laser features of the object that should be modelled and scanning technologies and photogrammetry tech- further applications of the 3D digital reconstruction niques have become mainstream in the last fifteen (connected with the purpose of the digital recon- years, and have greatly augmented the quantitative struction, why). The digital reconstruction also has its knowledge of important buildings and sites (see for own value because it allows elaborating hypotheses example the Cyark archives [4]). Both techniques al- and evaluating them through 3D modelling; hence it low digital modeling to start with very accurate geo- typically represents a moment of investigation. Lev- referenced data (e.g. archaeological evidence) of els of detail and objects organization are strictly de- morphologically complex sites. Every scan acquires pendent on the final aims of the project. A digi- morphological and dimensional information, repre- tal model created for the purpose of investigating sented by point clouds. These documents are con- the constructive characteristics of a vernacular build- verted through specific software packages into 3D ing (Di Mascio, 2013) or of an historical skyscraper surfaces and meshes or used as reference points to (Chiuini, 2011) has a different geometrical complex- model 3D objects (surfaces and solids). The passage ity, level of detail and organization of elements com- from point cloud to mesh remains an important tech- pared to a model aimed at simulate crowds' be- nical challenge that is considered by a large number haviour along the streets of an ancient city (Maïm et of computer scientists. The scans of remains located al., 2007). 3D modeling software, such as 3ds Max in different locations, also very far from each other, and Maya, are widespread solutions in digital recon- transformed in 3D objects, allow in a later stage to structions processes. In recent years, also BIM soft- digitally reassemble the fragments in a process that ware is being applied to heritage projects. However, can be called digital anastylosis (Thuswaldner, 2009; the use of a specific software package for the digital Chiuini, 2011). Because of the large myriad of tech- reconstruction process is strictly connected with the niques, devices, software and tools, however, the successive uses. The modeling process is a design granularity, level of detail and quality of point clouds problem: the design of an information system that are often different and not appropriate for the par- can make us understand, in its multifaceted complex- ticular object that is considered (too much or too lit- ity, a lost building, site, or place. tle detail). Furthermore, the fewer the building re- mains are, the bigger the necessity is to search and Further applications and analysis of the 3D collect other documents. In the case of totally lost model buildings, the only references may be represented The result of the digital reconstruction process can by archive records. The digital reconstructions of the often represent the starting point of further work that

DIGITAL HERITAGE - Volume 2 - eCAADe 34 | 515 can have several purposes. This work can to some ex- produced in service of a particular purpose, whether tent be articulated in seven main branches that iden- this be data collection for conservation or restoration tify further applications and analyses of the 3D digital projects, 3D graphic representations for touristic vis- model: analytical representations, photorealistic vi- its, historic documentation or other. Diverse mul- sualizations, information management systems, doc- tifaceted uses can be identified for a 3D digital re- umentation, simulations, augmented reality, virtual construction. On this basis, we are proposing seven reality. categories that represent further applications and analysis of the digitally reconstructed lost building. Dissemination These are very diverse products. Choosing to aim for The dissemination represents the last phase, but not any number of these products should be done soon the least important; it can be the main aim of a re- enough, in combination with defining the purpose search project or the final step, where part of the find- of the digital reconstruction. Namely, these products ings are packaged in ways that can be easily experi- all use some form of 3D or data, but they are very di- enced and understood by users. The results of the verse in nature and typically require a specific way of applications and analysis of the 3D digital reconstruc- modeling. In other words, in order to produce any tion constitute the main outcomes useful to spread of these products ('why'), one will need a different the information to a wider audience for different pur- digital reconstruction process ('how'). Furthermore, poses such as cultural tourism and education. All some products ('why') may be more appropriate for these products can be displayed in museums, on- lost, partially lost or transformed buildings ('what'). line or included in products such as books or DVDs. Furthermore, each of these applications can be com- To conclude, the digital reconstruction process typi- bined with the others. cally goes through four practical key phases, namely a data collection and analysis phase, a digital recon- Analytical Representations struction phase, a further application of the 3D dig- These analytical representations allow to analyze, ital reconstruction and a dissemination phase. Very document and communicate only a few aspects of diverse options exist in all these four phases, as is the building. Thanks to these graphic drawings it is schematically displayed in Figure 4. In order to make possible to split the characteristics of a building to appropriate choices in all four phases about the way better study and represent them individually or in in which the digital reconstruction process should sub-groups. Consequently, attention is paid to one take form, one should closely bear in mind the 'what' or more aspects, isolated from the whole building and 'why' of the digital reconstruction process. and analyzed through one or more graphic works. In fact, an overall view of the building can limit the anal- PRODUCTS OF THE 3D DIGITAL RECON- ysis of a particular characteristic. Axonometric ex- STRUCTION ploded views to study the aforementioned construc- tive characteristics of buildings are example analyti- Of course, in many cases, the 3D digital reconstruc- cal drawings. In (Webb et al., 2011), digital represen- tions of lost buildings are directly aimed at produc- tation techniques, inspired by forensic analysis, are ing specific product outputs. These are further ap- used to investigate, specific lines of enquiry related plications of the 3D digital reconstruction that form to selected features of a building. part of the reasons why a lost building is digitally re- constructed. Of course, as can also clearly be seen Photorealistic Visualizations in the last section, these products are closely linked This is the traditional approach that aims at very accu- to the actual purpose of the 3D digital reconstruc- rate architectural and realistic visualization of the lost tion. The end products should always be devised and building, including the lost parts. The reconstruction

516 | eCAADe 34 - DIGITAL HERITAGE - Volume 2 Figure 4 The How diagram with the four practical key phases.

of Trajan's Forum in Rome includes an archaeologi- mation portal, designed to allow updating and alter- cal investigation and a sophisticated modeling work native interpretations. (Packer 2001). A similar purpose has led the digital reconstruction of the Empire Exhibition held in Glas- Documentation gow (Scotland) in 1938 and subsequently dismantled The model allows producing architectural graphics [5]. and other information for historical studies, conser- vation, restoration or adaptive use. Rendered images Information Management Systems and animations of the digitally reconstructed portion Recent work in the field of archaeology, cultural her- of the cornice of the Chicago Stock Exchange Build- itage and architectural history tends to move be- ing document the relationship of the terra cotta en- yond digital 3D modeling into more specific tech- velope and the steel frame that resulted from the 3D nologies for knowledge organization. This includes digital reconstruction phase (Figure 5). The modeling data management, ontology engineering, multime- developed effectively as a heuristic process, which re- dia systems, immersive environments, virtual and vealed how an entire row of terra cotta blocks had augmented reality and semantic information mod- been damaged during construction because of lack eling (GIS and BIM). Thematic modeling integrated of coordination between the terra cotta production with GIS is becoming common practice in archaeol- and the steel design. When the digital terra cotta ogy. Human interfaces, interaction and usability have blocks were positioned on the model of the frame, it become an essential component of reconstructions. appeared that all blocks below the coping had been The 3D model can also be enriched with information chiselled on the back at the same level, which was pertaining to any knowledge domain using semantic confirmed by visual inspection of the fragments. The web technologies. The model can become an infor- portion removed from each piece lined up perfectly

DIGITAL HERITAGE - Volume 2 - eCAADe 34 | 517 with a horizontal steel angle mounted at the top of experience. The reconstruction of Hadrian's Villa [6] the steel brackets. This work, perhaps hastily exe- focuses not so much on architectural accuracy, but cuted while setting the terra cotta on site, cracked the on the analysis of astronomical alignments with spe- material causing water infiltration over time (Chiuini, cific artifacts on site, using the NASA calendar for 2011). the year 125 CE. Also digital characters (avatars) pro- vide realism to the experience by moving and talk- Simulations ing. This type of model can be used at different levels: Simulations can be interactive (e.g. for training pur- for the general public and for the historian. It is not poses) or devised for specialist applications (bearing just a visual representation of a space, but an instru- structures, lighting, acoustics, etc.) and can use dif- ment to analyze the architectural design intentions ferent technologies such as virtual reality. and historical hypothesis in an interdisciplinary envi- ronment. Augmented Reality Augmented reality applications allow overlapping A CRITICAL FRAMING FOR 3D DIGITAL RE- the virtual model on a real site using a portable/wear- CONSTRUCTIONS OF LOST BUILDINGS able device. In (Madsen et al. 2015) an augmented The overall diagram displayed in Figure 6 now pro- reality installation, that includes two interactive de- vides an excellent resource to compose a visual vices (a tabled connected to a large TV screen and an framework in which many existing and forthcoming hand-held tablet), has been developed to allow peo- digital reconstruction of lost buildings can be cat- ple to experience the visual appearance of the lost in- egorized.The diagram is composed by three main teriors of the chapel of Koldinghus Castle in Denmark. parts that represents likewise questions and impor- The chapel was destroyed and reconstructed several tant phases of a digital reconstruction process of lost time and what people can see today is a ruin resulted buildings: what, why and how. The first column is of a basic restoration undertaken in the 1970s (Mad- related to what. Hence, at the beginning it is neces- sen et al. 2015). sary to identify the lost building that is to be mod- Virtual Reality elled and its degree of loss. Reason and the identifi- cation of the building/site type are useful to provide Despite how it may seem, virtual tours have been both a more comprehensive overview of what is to around already for several years. In fact, it was pos- be modelled and clues to search reference buildings sible to experience, for the first time, a virtual tour al- that are essential for filling the unavoidable informa- ready in 1994, in the visitor center in the remains of tion gaps.The second column refers to the purpose Dudley castle in the West Midlands, England (Boland of the 3D digital reconstruction, namely why we are et al. 1996). This first virtual tour anticipates the re- undertaking this kind of study. At the same time, it is cent, and for several aspects, more advanced real- possible to define the products that we are aiming at; time virtual and interactive tours using game engines they represent a concrete reply to the purpose. How- technologies that have widely spread recently. Dig- ever, this is still a planning phase that can be updated ital modelling in general is today also conceived as and modified afterwards according to the available a way to embed information in a three-dimensional documentation.The last part of the diagram is con- representation of the physical world. The use of stituted by the four key phases from Data Collection game engines and VR device allow to navigate and to Dissemination passing through the actual 3D Dig- explore the reconstructed buildings in a virtual envi- ital Reconstruction and its further applications. The ronment; it can include interactive components and how phase is oriented in the practical creation of a fi- metadata. The integration of dynamic systems and nal product that replies to a specific purpose and dis- physical simulations such as gravity allow a realistic

518 | eCAADe 34 - DIGITAL HERITAGE - Volume 2 Figure 5 Rendered images that document the relationship between the terra cotta and the steel frame of the cornice of the Chicago Stock Exchange Building (Source: M. Chiuini).

Figure 6 The final diagram that represents visual framework in which many existing and forthcoming digital reconstruction of lost buildings can be categorized. The whole process is constituted by 6 main steps and influenced by disciplinary areas.

seminate the result to a selected audience. personal experiences in the field. The big amount of research about 3D digital reconstruction of lost CONCLUSIONS AND FUTURE DEVELOP- buildings, developed in a span of over 30 years, pre- MENTS sented a wide variety of theoretical positions, meth- ods and tools influenced by disciplinary areas such as This piece of writing presented a first critical framing architecture and archaeology. However, counter this of 3D digital reconstruction of lost buildings based on amount and variety of research, we found the almost the result of an examination of example projects and

DIGITAL HERITAGE - Volume 2 - eCAADe 34 | 519 total absence of a comprehensive critical assessment. the non-existing within an urban context', Proceed- This piece of writing proposes a critical framing that ings of the 15th CAADRIA Conference, Hong Kong, suggests a way of organizing these research initia- China, pp. 63-72 Di Mascio, D 2010 'Preserving memories with digital me- tives by replying to three main questions that de- dia: a methodology for the reconstruction of Castel- fine every digital reconstruction process: what, why nuovo Village', Proceedings of the 15th CAADRIA Con- and how. We recognized that the category of lost ference, Hong Kong, China, pp. 83-92 buildings (what) is not restricted to heritage but con- Di Mascio, D 2013 'Understanding and Managing the sists of every building, including the pavilions of re- Constructive Characteristics of Vernacular Architec- cent world fairs. For this reason the theoretical ap- ture. Two raw earth houses', Proceedings of the 31st eCAADe Conference - Volume 2, Delft, The Nether- proaches, the aims (why), and the technologies and lands, pp. 435-444 methodologies (how) can be varied and not con- Maïm, J, Haegler, S, Yersin, B, Mueller, P,Thalmann, D and fined to archaeology and architectural history, even Van Gool, L 2007 'Populating ancient Pompeii with if these disciplines represent an important number of crowds of virtual romans', Proceedings of the 8th In- investigation. Moreover, the piece of writing identi- ternational conference on Virtual Reality, Archaeology fies a set of products of the 3D digital reconstructions and Intelligent Cultural Heritage (VAST, Aire-la-Ville, Switzerland, pp. 109-116 that form part of the reasons why a lost building is Novitski, BJ 1998, Rendering Real and Imagined Buildings, digitally reconstructed. These products are the result Rockport Publisher, Gloucester, Massachusetts, USA of further applications and analysis of the 3D digital Packer, J 2001, The Forum of Trajan in Rome. A Study of reconstruction; they show, organize, communicate, the Monument in Brief., University of California Press, deepen and enrich the knowledge about a specific Berkeley, California, USA lost building for several purposes. This first critical Pauwels, P and Di Mascio, D 2014, 'Interpreting metadata and ontologies of virtual heritage artefacts', Interna- framing constitutes the basis of further studies, such tional Journal of Heritage in the Digital Era, 3(3), pp. as a state-of-the-art review. 531-555 Sdegno, A 2012 'Physical and Digital Models for Elec- REFERENCES tronic Spaces: The 3D virtual re-building of the Philips Pavilion by Le Corbusier', Proceedings of the Anderson, EF, McLoughlin, L, Liarokapis, F, Peters, C, 30th eCAADe Conference - Volume 1, Prague, Czech Petridis, P and de Freitas, S 2009 'Serious games Republic, pp. 747-754 in cultural heritage', 10th International Symposium Thuswaldner, B, Flory, S, Kalasek, R, Hofer, M, Huang, Qi- on Virtual Reality, Archaeology and Cultural Heritage Xing and Thur, H 2009, 'Digital Anastylosis of the Oc- VAST State of the Art Reports tagon in Ephesos', JournalonComputingandCultural Boland, P and Johnson, C 1996 'Archaeology as com- Heritage, 2(1), pp. 1-30 puter visualization: 'Virtual tours' of Dudley Castle c. Webb, N and Brown, A 2011 'Augmenting critique of lost 1550', Imaging the Past: Electronic Imaging and Com- or unbuilt works of architecture using digitally me- puter Graphics in Museums and Archaeology, Occa- diated techniques', Proceedings of the 29th eCAADe sional Papers 114, British Museum Press, p. 227–234 Conference, Ljubljana, Slovenia, pp. 942-950 Chiuini, M 2011 'Digital Reconstruction of the Chicago [1] http://3dvisa.cch.kcl.ac.uk/project12.html Stock Exchange', Digital Media and Its Applications in [2] http://www.digitale-kunstgeschichte.de/w/images Cultural Heritage. Proceedings of the DMACH Confer- /0/0f/Messemer_Heike_The_Beginnings_of_Digita ence, Amman, Jordan, p. 10 l_Visualization_of_Historical_Architecture_IN Glancey, J 2015, Lost Buildings, Goodman Books, London, _Virtual_Palaces_Part_II_2016_p_21-54.pdf United Kingdom [3] http://www.courtresidences.eu/index.php/publica Madsen, JB and Madsen, CB 2015, 'Handheld Visual Rep- tions/e-Publications/#Volume%203 resentation of a Castle Chapel Ruin', ACM Journal on [4] http://www.cyark.org/ Computing and Cultural Heritage, Vol. 9(No. 1), p. 18 [5] http://www.empireexhibition.com/ Martens, B and Peter, H 2010 'Displacing the frontiers of [6] http://idialab.org/nsf-funded-virtual-simulatio reconstructed cultural heritage. Representation of n-of-hadrians-villa/

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