The Making Of Intervisibility Maps With Computer And Plotter

Manual construction of intervisibility maps, based on topographical contour maps, is a laborious procedure of questionable accuracy. This paper describes the methodology of a computer program named HIDE which computes and draws intervisibility maps with a computer and plotter, based on a digital terrain model of the area observed. Instead of finding stretches of 'dead ground' along profiles radiating from an observation point, each point of the digital terrain model is checked individually for its visibility from the given point of observation. The primary result of the computations executed by program HIDE is, therefore, a binary matrix of either seen or hidden points which then serves as the basis for an appropriate graphic depiction. The use of computer and plotter assistance also facilitates the creation of graduated and combined intervisibility maps. La preparation manuelle de cartes de reconstitution visuelle a partir de cartes topographiques est un processus laborieux d'une exactitude discutable. L...