The paper presents a unique solution to the 3D visibility problem in built-up areas. A 3D visibility algorithm based on an analytic solution for basic building structures is introduced. A building structure is presented as a continuous parameterization approximating of the building’s corners. The algorithm quickly generates the visible surfaces' boundary of a single building. Using simple geometric operations of projections and intersections between visible pyramid volumes, hidden surfaces between buildings are rapidly computed. The algorithm, demonstrated with a schematic structure of an urban built-up environment and compared to the Line of Sight (LOS) method, demonstrates the computation time efficiency.

Whereas the common visibility methods (LOS approach) require scanning all the object’s points, the presented solution, by applying the continuous parameterization approximating of the building’s corners, is successfully avoiding the need to handle each point separately. As a result, the performance of the presented solution is much better than the common methods and for the analyzed samples the improvement time ratio was about 1000 times. The basic building structure can be modified to complex urban structures by merging together a number of basic structures.

The main contribution of the presented method in this paper is that it does not require special hardware, and is suitable for on-line computations based on the algorithms' performances. The visibility solution is exact, defining a simple problem that can be a basic form of other complicated environments. Read More