Shortest Descending Paths through Given Faces
نویسندگان
چکیده
A path from s to t on a polyhedral terrain is descending if the height of a point p never increases while we move p along the path from s to t. No efficient algorithm is known to find a shortest descending path from s to t in a polyhedral terrain. We give some properties of such paths. In the case where the face sequence is specified, we show that the shortest descending path is unique, and give an 2-approximation algorithm that computes the path in O(n log( 12 )) time.
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ورودعنوان ژورنال:
- Comput. Geom.
دوره 42 شماره
صفحات -
تاریخ انتشار 2006