THE REVERSE MODELLING REALIZED BY DIGITAL SCANS AND FOTOMODELLAZIONE: BASED ON POST-PROCESSING COMPARED SEVERAL NOTEWORTHY EPISODES CONTAINED IN THE BASILICAL COMPLEX OF SAN LORENZO FUORI LE MURA IN ROME

摘要

In the last decade, the subject area of the survey, and also that of representation, have undergone major changes with the intr oduction and use of advanced technologies that ha ve revolutionized both the operational proce sses dedicated to the withdrawal of the measures that those graphic display data in terms of return and performance. The three-dimensional vision deriving from direct observation, or photogrammetric instrumental with the application of images, constitutes the most complete display means of the formal, morphological and material aspects of the detected object. 3D modeling offers many advant ages, such as managing even the most complex geometric surfaces and its use is investing many sectors: in particular in the field of architecture serves many purposes including documentation, representation, diagnostics, materials and degradation, the enhancement and conservation of the proper ty, etc.. The laser scanner technology together with that of fotomodellazione, is aimed to the acquisition, modeling and rendering three-dimensional (3D) surface observed physical. The laser system to scan, as well as that of photographing, provides as a direct result of the measurement session a set of three-dimens ional coordinates, in a reference system linked with the instrument. The high amount of sampled data, in the order of thousands per second, allows to obtain a high level of detail offering an acquisition that cou ld be called pseudo-continuous. In this context, there is a complex major project work on the Basilica di San Lorenzo flm in Roma, - whose first partial results have recently been published - in the course of an activity which has been carried out to study and research for the establishment of proce dures for processing the most appropriate and va lid to be applied during post-processing for the eventual realization of a proper three-dimensional model. This paper will illustrate, through the analysis of some significant episodes of the Basilica, as the criteria adopted for the choices made at this stage ha ve been crucial to the final outcome.