Convex and Concave Vertices on a Simple Closed Curve in the Triangular Grid

  • Lidija ČomićEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11414)


We propose a classification of convex and concave vertices on a simple closed curve in the triangular grid into two types, based on the angle turn the curve makes at the vertex. We prove a combinatorial property for the number of convex and concave vertices of different types.


Digital topology Triangular grid Convex and concave vertices Salient and reentrant vertices Simple closed curve 



We thank the reviewers for reading the paper carefully, spotting some gaps in the first version of the proof and making constructive suggestions. This work has been partially supported by the Ministry of Education and Science of the Republic of Serbia within the Project No. 34014.


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Authors and Affiliations

  1. 1.Faculty of Technical SciencesUniversity of Novi SadNovi SadSerbia

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