Since restitution of the volumes of wall art and their supports has become one of the essential requirements of mapping, recording techniques have evolved in recent years. Driven by scientific concerns, 3D technologies now allow the acquisition of data useful for the analysis of works (measurements, cross-sections and profiles of objects, highly accurate assessments of both walls and works of art and simulations, including virtual repositioning, variation of light sources, virtual connection of decorated stone blocks, and homothetic comparisons of forms). It also allows works to be given back to the public, but without replacing the analytical mapping, which does not fulfil the same function.
The four sculpted shelters benefited from 3D scans of their overall topography and of their walls and blocks. This is carried out at different levels of accuracy based on the nature of the scanned areas (natural, sculpted, engraved). A laser distance meter performs a spatial measurement by emitting a beam that scans the surface. It provides a scan in the form of files of X Y Z coordinates. A digital camera captures colour images used in the initial mapping, supplemented by photographic images. A digital surface model (DSM) is then created by assembling the harmonised files, and the reference database can be exported in various file formats.
