Workflow for Line-of-Sight (LOS) analysis in GIS (ArcGIS Desktop/PRO software release): the video shows the setup of hypothetical observing points, evenly distributed through the space of the virtually reconstructed house of Caecilius Iucundus (height on the ground floor 1.65 m, space interval 0.2 m). LOS algorithm enabled us to generate a vertical map featuring the percentage of visual exposure of the fresco’s surface and a horizontal map of cumulative visibility of the fresco from each observing location