Results 221 to 230 of about 4,255,094 (265)

Convexifying polygons with simple projections

Information Processing Letters, 2001
Abstract It is known that not all polygons in 3D can be convexified when crossing edges are not permitted during any motion. In this paper we prove that if a 3D polygon admits a non-crossing orthogonal projection onto some plane, then the 3D polygon can be convexified.
Jorge Alberto Calvo, Danny Krizanc, Godfried T. Toussaint, Michael Soss, Pat Morin   +4 more
openaire   +2 more sources

Circle Shooting in a Simple Polygon

Journal of Algorithms, 1993
Abstract Consider the following problem: Given a simple n-gon P , preprocess it so that for a query circle π and a point s on π, one can quickly compute Φ( P , π, s), the first intersection point between P and π as we follow π from s in clockwise direction.
Micha Sharir, Pankaj K. Agarwal
openaire   +2 more sources

Exploring Simple Grid Polygons

2005
We investigate the online exploration problem of a short-sighted mobile robot moving in an unknown cellular room without obstacles. The robot has a very limited sensor; it can determine only which of the four cells adjacent to its current position are free and which are blocked, i.e., unaccessible for the robot.
Rolf Klein, Elmar Langetepe, Tom Kamphans, Christian Icking   +3 more
openaire   +1 more source

Maintaining the Visibility Graph of a Dynamic Simple Polygon

International Conference on Algorithms and Discrete Applied Mathematics, 2019
Tameem Choudhury, R. Inkulu
semanticscholar   +1 more source

DETERMINING THE SEPARATION OF SIMPLE POLYGONS

International Journal of Computational Geometry & Applications, 1994
Given simple polygons P and Q, their separation, denoted by σ(P, Q), is defined to be the minimum distance between their boundaries. We present a parallel algorithm for finding a closest pair among all pairs (p, q), p ∈ P and q ∈ Q. The algorithm runs in O ( log n) time using O(n) processors on a CREW PRAM, where n = |P| + |Q|.
openaire   +2 more sources

On Simple Polygonalizations with Optimal Area

Discrete & Computational Geometry, 2000
We discuss the problem of finding a simple polygonalization for a given set of vertices P that has optimal area. We show that these problems are very closely related to problems of optimizing the number of points from a set Q in a simple polygon with vertex set P and prove that it is NP-complete to find a minimum weight polygon or a maximum weight ...
openaire   +1 more source

On-Line Searching in Simple Polygons

1999
In this paper we study the problem of a robot searching for a visually recognizable target in an unknown simple polygon. We present two algorithms. Both work for arbitrarily oriented polygons. The search cost is proportional to the distance traveled by the robot. We use competitive analysis to judge the performance of our strategies. The first one is a
openaire   +2 more sources

Decomposing a Simple Polygon into Trapezoids

2007
Chazelle's triangulation [1] forms today the common basis for linear-time Euclidean shortest path (ESP) calculations (where start and end point are given within a simple polygon). This paper provides an alternative method for subdividing a simple polygon into "basic shapes", using trapezoids instead of triangles.
Fajie Li, Reinhard Klette
openaire   +2 more sources

ON HAMILTONIAN TRIANGULATIONS IN SIMPLE POLYGONS

International Journal of Computational Geometry & Applications, 1999
An n-vertex simple polygon P is said to have a Hamiltonian Triangulation if it has a triangulation whose dual graph contains a hamiltonian path. Such triangulations are useful in fast rendering engines in Computer Graphics. We give a new characterization of polygons with hamiltonian triangulations and use it to devise O(n log  n)-time algorithms to ...
openaire   +1 more source

The VC-Dimension of Visibility on the Boundary of a Simple Polygon

International Symposium on Algorithms and Computation, 2015
Matt Gibson, Erik Krohn, Qing Wang
semanticscholar   +1 more source