Which survey for which digital model: critical analysis and interconnections

The process of "critical analysis of measurement" and "taking the measure", before the current modern surveying techniques, followed a process that presupposed design choices by the surveyor/researcher. It depended on the object of study and on the purpose of the survey. These choices lead to both elaborated two-dimensional drawings and digital models (verified and controlled), from whom starting new studies. It is useful and appropriate, today, to make some reflections whether the process could be enriched, implemented and "slimmed down", to obtain an informative model that can be both "read" and “write” by multiple users according to their purposes of study. Applying Building information model to heritage architecture could lead to build two different models. On one side, a so-called ideal model, which refers to spatial-geometric drawing study as an act of synthesis, on the other an as-real model, which answers the mimetic requirements in model geometry. Nevertheless, it is possible to go beyond these differences using a proper interoperable building information model to organize semantic enriched geometries and integrating the model with the digital survey. Effectively, some tools allow users to integrate the surveyed points into the model as an object. This leads users to pay attention again on building the model as a critical act, to articulate the architecture's system.