Walking in the visibility complex with applications to visibility polygons and dynamic visibility
نویسنده
چکیده
We first consider the set of faces of the complex representing rays issued from a given object. We define an order on these faces and show, once the visibility complex is computed, how to visit all of them with no additional data structure in optimal time O(kf ), where kf is the number of faces visited. Then we show how to use this walk to perform a topological sweep of the vertices incident to these faces in optimal time O(kv), where kv is the number of these vertices, still with no additional data structure.
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