F G Representing the Visibility Structure of a Polyhedral Terrain through a Horizon Map : Digital Terrain Models, Visibility, Data Structures, Horizons : a Horizon-based Visibility Map for Terrains
نویسندگان
چکیده
horizon map Representing the Visibility Structure of a Polyhedral Terrain through a Horizon Map We present a model for describing the visibility of a polyhedral terrain from a xed viewpoint, based on a collection of nested horizons. We brie y introduce the concepts of mathematical and digital terrain models, and some background notions for visibility problems on terrains. Then, we de ne horizons on a polyhedral terrain, and introduce a visibility model, that we call the . We present a construction algorithm and a data structure for encoding the horizon map, and show how it can be used for solving point visibility queries with respect to a xed viewpoint.
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