Visibility maintenance of a moving segment observer inside polygons with holes
نویسندگان
چکیده
We analyze how to efficiently maintain and update the visibility polygons for a segment observer moving in a polygonal domain. The space and time requirements for preprocessing are O(n) and after preprocessing, visibility change events for weak and strong visibility can be handled in O(log |VP|) and O(log(|VP1| + |VP2|)) respectively, or O(log n) in which |VP| is the size of the line segment’s visibility polygon and |VP1| and |VP2| represent the number of vertices in the visibility polygons of the line segment endpoints.
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