Combining on-site and off-site analysis: towards a new paradigm for cultural heritage surveys

In recent decades, cultural heritage survey practices have significantly evolved due to the increasing use of digitization tools providing quick and easy access to faithful copies of study objects. While these digital data have clear advantages, especially in terms of geometric characterization, they also introduce a paradigm shift by outsourcing ex situ most of the analysis activities. This break between real and virtual working environments now raises new issues, both in terms of data dispersion and knowledge correlation in multidisciplinary teams. Benefiting from the fields of information systems and augmented reality, we proposed an integrated approach allowing the fusion of geometric, visual and semantic features in a single platform. Today, this proof of concept leads to new perspectives for the production of semantically enriched digital data. In this paper, we intend to explore the different possibilities in terms of implementation and their benefits for cultural heritage survey.

Versioning Virtual Reconstruction Hypotheses: Revealing Counterfactual Trajectories of the Fallen Voussoirs of Notre-Dame de Paris using Reasoning and 2D/3D Visualization

Virtual reconstruction should move beyond merely presenting 3D models by documenting the scientific context and reasoning underlying the reconstruction process. For instance, the collapsed arch in the nave of Notre-Dame de Paris serves as a case study to make explicit the reconstruction argumentation encapsulated in relation to the spatial configuration of the arch and the voussoirs. The experiment is twofold: (1) setting up of the 3D dataset where the hypotheses are modeled as versions using logic programming, and (2) evaluating the scientific narrative of reconstruction through both a custom 2D-3D visualization and competency questions on the enriched 3D data. Formalization, reasoning, and visualization are combined to explore the nonlinear scientific hypotheses and narrative of the reconstruction. The results explicitly show both the factual information on the physical and digital objects, as well as the counterfactual propositions allowing the reasoning at play in the reconstruction. The hypotheses are visualized as counterfactual trajectories creating an open dynamic visualization that makes possible the spatialized querying of conflicting interpretations and embedded memory in place.