Result: Optimally computing the shortest weakly visible subedge of a simple polygon

Title:
Optimally computing the shortest weakly visible subedge of a simple polygon
Authors:
CHEN, D. Z
Source:
Journal of algorithms (Print). 20(3):459-478
Publisher Information:
San Diego, CA: Elsevier, 1996.
Publication Year:
1996
Physical Description:
print, 24 ref
Original Material:
INIST-CNRS
Subject Terms:
Computer science, Informatique, Mathematics, Mathématiques, Sciences exactes et technologie, Exact sciences and technology, Sciences appliquees, Applied sciences, Informatique; automatique theorique; systemes, Computer science; control theory; systems, Informatique théorique, Theoretical computing, Algorithmique. Calculabilité. Arithmétique ordinateur, Algorithmics. Computability. Computer arithmetics, Recherche information. Graphe, Information retrieval. Graph, Algorithme optimal, Optimal algorithm, Algoritmo óptimo, Algorithme parallèle, Parallel algorithms, Plus court chemin, Shortest path, Camino más corto, Polygone, Polygon, Polígono, Segment droite, Line segment, Segmento recta, Algorithme séquentiel, Sequential algorithm
Document Type:
Academic journal Article
File Description:
text
Language:
English
Author Affiliations:
Department of Computer Science and Engineering, University of Notre Dame, Notre Dame, Indiana 46556, United States
ISSN:
0196-6774
Access URL:
http://pascal-francis.inist.fr/vibad/index.php?action=search&terms=3092691
Rights:
Copyright 1996 INIST-CNRS
CC BY 4.0
Sauf mention contraire ci-dessus, le contenu de cette notice bibliographique peut être utilisé dans le cadre d’une licence CC BY 4.0 Inist-CNRS / Unless otherwise stated above, the content of this bibliographic record may be used under a CC BY 4.0 licence by Inist-CNRS / A menos que se haya señalado antes, el contenido de este registro bibliográfico puede ser utilizado al amparo de una licencia CC BY 4.0 Inist-CNRS
Notes:
Computer science; theoretical automation; systems
Accession Number:
edscal.3092691
Database:
PASCAL Archive

Further Information

Given an n-vertex simple polygon P, the problem of computing the shortest weakly visible subedge of P is that of finding a shortest line segment s on the boundary of P such that P is weakly visible from s (if s exists). In this paper, we present new geometric observations that are useful for solving this problem. Based on these geometric observations, we obtain optimal sequential and parallel algorithms for solving this problem. Our sequential algorithm runs in O(n) time, and our parallel algorithm runs in O(log n) time using O(n/log n) processors in the CREW PRAM computational model. Using the previously best known sequential algorithms to solve this problem would take O(n2) time. We also give geometric observations that lead to extremely simple and optimal algorithms for solving, both sequentially and in parallel, the case of this problem where the polygons are rectilinear.