Computing visibility maps on a digital terrain model

  • Leila De Floriani
  • Paola Magillo
Data Models for Spatial and Temporal Data
Part of the Lecture Notes in Computer Science book series (LNCS, volume 716)


In this paper, we present a model based on a collection of nested horizons to describe the visibility of a terrain with respect to a viewpoint. We introduce first a formalization of mathematical and digital terrain models, and some background notions for visibility problems on terrains. Then, we define horizons and shadows on a polyhedral terrain, and introduce a few horizon-based visibility maps of a terrain. Finally, we present two algorithms for building the nested horizons on a polyhedral terrain. An application to the solution of point-to-point visibility queries are briefly discussed.


Digital Terrain Model Active Edge Sweep Process Visible Portion Visibility Query 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 1993

Authors and Affiliations

  • Leila De Floriani
    • 1
  • Paola Magillo
    • 1
  1. 1.Department of Computer and Information SciencesUniversity of GenovaGenovaItaly

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