3 citations · 7 across the 8 of their papers we have counts for
8 papers
Guarding Polyominoes Under -Hop Visibility
Omrit Filtser, Erik Krohn, Bengt J. Nilsson +2
We study the Art Gallery Problem under -hop visibility in polyominoes. In this visibility model, two unit squares of a polyomino can see each other if and only if the shortest p…
Opposing Half Guards
Erik Krohn, Bengt J. Nilsson, Christiane Schmidt
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…
On the Complexity of Half-Guarding Monotone Polygons
Hannah Miller Hillberg, Erik Krohn, Alex Pahlow
We consider a variant of the art gallery problem where all guards are limited to seeing to the right inside a monotone polygon. We call such guards: half-guards. We provide a polyn…
Terrain Visibility Graphs: Persistence is Not Enough
Safwa Ameer, Matt Gibson-Lopez, Erik Krohn +2
In this paper, we consider the Visibility Graph Recognition and Reconstruction problems in the context of terrains. Here, we are given a graph with labeled vertices $v_0, v_1,…
A Characterization of Visibility Graphs for Pseudo-Polygons
Matt Gibson, Erik Krohn, Qing Wang
In this paper, we give a characterization of the visibility graphs of pseudo-polygons. We first identify some key combinatorial properties of pseudo-polygons, and we then give a se…
The Complexity of Guarding Terrains
James King, Erik Krohn
A set of points on a 1.5-dimensional terrain, also known as an -monotone polygonal chain, is said to guard the terrain if any point on the terrain is 'seen' by a point in $G…