We extend a dynamic-programming algorithm of Keil and Snoeyink for finding a minimum convex decomposition of a simple polygon to the case when both convex polygons and pseudo-triangles are allowed. Our algorithm determines a minimum pseudo-convex decomposition of a simple polygon in O(n) time where n is the number of the vertices of the polygon. In this way we obtain a well-structured decomposi...

This paper considers reconngurations of polygons, where each polygon edge is a rigid link, no two of which can cross during the motion. We prove that one can reconngure any monotone polygon into a convex polygon; a polygon is monotone if any vertical line intersects the interior at a (possibly empty) interval. Our algorithm computes in O(n 2) time a sequence of O(n 2) moves, each of which rotat...

Abstract A topological relationship is a key factor in the spatial data processing. Aiming at problem of similarity measurement when dimension objects changes process map generalization, this paper proposes method based on global concept neighborhood graph. Firstly, all relationships that can be described by nine intersection model are abstracted, generalized, and classified, classified point/p...

If we construct isosceles polygon Pa k with (k − 1) sides of the same length over each side of regular polygon Pb n , with n sides, we get a new equilateral polygon P a,δ N with N = (k− 1)n sides of the same length and with different inner angles. Such polygon is called equilateral semi-regular polygon. This paper deals with metric properties of general semi-regular polygons Pa N , with given s...

We consider the navigation problem of a robot from a starting point S to a target point T inside an unknown rectilinear polygon. The robot knows the directions of the points S and T and it can detect the edges of the polygon through its tactile sensors. We present a competitive strategy for the robot to reach the target T . The competitive ratio of our strategy is 6 4:5dðj 1Þðjþ 2Þ þOð1Þ, where...

We extend the concept of the polygon visible from a source point S in a simple polygon by considering visibility with two types of reeection, specular and diiuse. In specular reeection a light ray reeects from an edge of the polygon according to the rule: the angle of incidence equals the angle of reeection. In diiuse reeection a light ray reeects from an edge of the polygon in all inward direc...

ABSTRACT: In this paper a new algorithm has been proposed which can fix the problem of WeilerAtherton algorithm. The problem of Weiler-Atherton algorithm lies in clipping self-intersecting polygon. Clipping self-intersecting polygon is not considered in Weiler-Atherton algorithm and hence it is also a main disadvantage of this algorithm. In our new algorithm a self-intersecting polygon has been...