On Guarding Orthogonal Polygons with Sliding Cameras [article]

Therese Biedl, Timothy M. Chan, Stephanie Lee, Saeed Mehrabi, Fabrizio Montecchiani, Hamideh Vosoughpour
2016 arXiv   pre-print
A sliding camera inside an orthogonal polygon P is a point guard that travels back and forth along an orthogonal line segment γ in P. The sliding camera g can see a point p in P if the perpendicular from p onto γ is inside P. In this paper, we give the first constant-factor approximation algorithm for the problem of guarding P with the minimum number of sliding cameras. Next, we show that the sliding guards problem is linear-time solvable if the (suitably defined) dual graph of the polygon has
more » ... ounded treewidth. Finally, we study art gallery theorems for sliding cameras, thus, give upper and lower bounds in terms of the number of guards needed relative to the number of vertices n.
arXiv:1604.07099v1 fatcat:45wwxekczzdfvorx5bziefv6lm