We study the art gallery problem for opposing half guards: guards that can either see to their left or to their right only. We present art gallery theorems, show that the location of half guards in 2-guardable polygons is not restricted to extensions, show that the problem is NP-hard in monotone polygons, and present approximation algorithms for spiral and staircase polygons.
翻译:我们研究了对立半个警卫的美术席问题:要么看左,要么只看右。我们提出了美术席定理,显示在两个可保护多边形中半个警卫的位置并不限于扩展,表明问题在于单调多边形中的NP硬,并提出了螺旋形和楼梯多边形的近似算法。