The digital reconstruction of architectural and urban complexes which were demolished, transformed or have been only theoretically conceived, remaining 'on paper', is now a tool of considerable heuristic value, allowing to preserve, interpret and create new images of cultural heritages that no longer exist in their original shape or never reached a material construction. The tools, methods and techniques of representation (graphical analysis, two and three-dimensional modeling, animation, prototyping) should be carefully chosen, case by case, in order to interpret properly the basic data and create original interpretations, using as research sources and ideas not only the archival drawings and any surviving vestiges, but also the autograph writings and the more inspired analysis developed by the architecture critics. The examination of several international case studies, and also some experiences personally conducted highlights the different strategies used for the preservation of the memory of such heritage.
TopBackground
The theme of the digital reconstruction of architectural and urban complexes is currently the subject of interest for many scholars and a field of convergence of different disciplinary viewpoints ranging from history of architecture, urban studies and environmental psychology.
This chapter privileges the point of view that takes as the central moment of the reconstruction the creation of interpretative digital models of a series of knowledge assumed through interdisciplinary researches. The relationship between architectural and urban dimensions is thought seamless: the architectural complex, object of study, must be related to the urban context in which it was designed or it spent a special time in its life or it could live today, and the reciprocal transformations must be carefully recorded. In this way the object itself takes on an urban meaning. There could be several aims of reconstruction that, in this research ambit, goes beyond the mere iconographic documentation, to provide scientifically plausible readings of the analysed phenomena.
Several reconstruction techniques are inspired by Pagnano, Docci and Albisinni's theories and methodologies of graphical analysis, applied to the design drawing as well to realize buildings, thanks to which the drawing can be identified with the model of understanding (Pagnano, 1975; Docci, 2009; Albisinni, 2011).
The scholars, adopting this method, re-draw and, or, re-model the space and use the graphic model as scientists reproducing artificially a certain phenomenon in the laboratory.
Reconstructive 3D modeling allows reviving an architecture and its relationships with the context, whether it is partly, or totally, lost, or hidden in the body of a building heavily altered, or, finally, it is going to be irreversibly transformed.
Representation and communication concern the knowledge data and their interpretation, resulting from the documentation phases. The digital models are the most useful database for collecting and synthesizing these analyses.
The modeling is therefore a cognitive strategy in which the idea of similarity, in comparison with the reality, plays a decisive role, a strategy that is utilized in different ways depending on which kind of model it is going to carry out (Gaiani, 2004)
There are several stages in the 3D reconstruction of a built complex. These include the gathering of the source information, the interpretation of this information, the comparison with contemporaneous examples, the development of 2D blueprints and/or 3D geometric (or parametric) models of the building and its context, the texture mapping, the addition of lights and, finally, the rendering.
Transforming several drawings into a digital model is a process which changes one model into another and deserves some attention. It is, as a matter of fact, not a simple variation without alteration of contents, but, on the contrary, it modifies, from time to time, “the wealth of the model, its expressive potentiality. In fact, the transmutations of the models are moved by the interpretative intent of the scholar, and they converge, therefore, toward an abstract model... that we can identify in the project idea” (Migliari, 2004).