Retraced memories - virtual reconstruction of an architectural landmark

Abstract

<p class="VARAbstract">This paper addresses the challenge of digitally reconstructing ruined architectural sites and retracing their history, in order to virtually recompose their geometrical, stylistic and material integrity. To this end, the research team analyzed the ruins of the church of Santa Maria de Monasterio Albo, located in the ancient village of Misterbianco (Sicily) and destroyed (together with the entire hamlet) by the 1669 eruption of Mount Etna. In the last years, some excavation campaigns brought the church to the light, unveiling the remains of the main portal and six altars, which are one of the most remarkable examples of Mannerist art in eastern Sicily. This research aimed to three-dimensional (3D) reconstruct both the altars and the portal, ideally reviving their original 17<sup>th</sup> century configuration. This goal was achieved through an in-depth archival research (documents dating back to the years between 1300 and 1666 were consulted), an analysis of Classic and Renaissance treatises, and two integrated digital survey campaigns (laser scans and photogrammetry). The outcome is represented by the 3D models of the seven artifacts, which include surviving parts reconstructed as photogrammetric meshes, several fragments were placed in their likely early location through a virtual anastylosis, and NURBS (Non Uniform Rational Basis-Splines) surfaces (recreating the no longer existing elements). The latter were 3D modelled based on the treatises (which provided information on the correct proportioning) or in analogy with other coeval similar artifacts. Overall, the digital reconstruction was based on the ethical principles of transparency of the intervention, recognition of non-original additions and distinction between evidence and hypothesis, according to the London Charter and the Seville Principles. The experimentation provides a valid support for possible interventions in the real world and is the starting point to develop a digital archive of the site, which would make the different accuracy levels the reconstruction explicit.</p><p><strong>Highlights:</strong></p><ul><li><p>3D virtual reconstruction is effective to visualize and bring back to life ruined architectural artefacts.</p></li><li><p>Information about the artefacts original appearance was harvested through digital survey campaigns, archival documents, and comparisons with iconographic sources and coeval buildings.</p></li><li><p>The 3D reconstruction follows ethical principles of transparency and combines photogrammetric meshes (partly relocated through a virtual anastylosis) and NURBS surfaces.</p></li></ul>

Continuidad entre NURBS

“…"Blend Surface" permite obtener el máximo nivel de continuidad entre superficies en Rhinoceros, llegando hasta nivel G 4 . Sin embargo, en muchas ocasiones los niveles G 1 y G 2 , buscando continuidad en tangentes y curvatura, será el objetivo buscado, y podemos optar a una mayor cantidad de herramientas que flexibilizan las opciones de diseño (Felicetti, 2021;Fallica, 2021;del Blanco, 2021).…”

Systematic integration of 2D and 3D sources for the virtual reconstruction of lost heritage artefacts: the equestrian monument of Francesco III d’Este (1774–1796, Modena, Italy)

“…In the last decades, the role of 3D techniques in the field of archaeological heritage has assumed, on the one hand, an increasingly importance for the web diffusion of cultural contents, public outreach and education [1][2][3][4], also thanks to different mediums of visualization [5] that improves the spread of Cultural Heritage artefacts [6]. On the other hand, 3D technologies have a key role in documenting and supporting archaeologists who deal with continuous work of restoration and their associated studies, generating 3D models for archival purposes, for conservation records [7][8][9], for 3D visualization [10][11][12][13][14] and reconstructive interpretation of lost artefacts [15][16][17][18][19][20][21]. In [22], Lai et al stressed the importance to use 3D technologies as a tool to improve archaeological research and to increase the production of information from archaeological data to 4D analysis and interpretation.…”

“…Spallone [37] presented different strategies for the preservation of architectures subjected to demolition or transformation, and then focused on a case study in which critical bibliography, archival sources and digital reconstruction are combined. Besides the high number of examples of 3D surveying of architectural heritage, we highlight the contribution of research works [15][16][17][18][19]38] dealing with the virtual reconstructions of lost buildings or archaeological sites.…”

Reconstrucción virtual del esquileo del marqués de Perales en El Espinar (Segovia)

“…• los elementos que articulan la arquitectura (Fallica, Garozzo & Santagati, 2021;Martínez, 2018;Patay-Horváth, 2013);…”