Schnyder Woods for Higher Genus Triangulated Surfaces, with Applications to Encoding
نویسنده
چکیده
Schnyder woods are a well-known combinatorial structure for plane triangulations, which yields a decomposition into 3 spanning trees. We extend here definitions and algorithms for Schnyder woods to closed orientable surfaces of arbitrary genus. In particular, we describe a method to traverse a triangulation of genus g and compute a so-called g-Schnyder wood on the way. As an application, we give a procedure to encode a triangulation of genus g and n vertices in 4n+O(g log(n)) bits. This matches the worst-case encoding rate of Edgebreaker in positive genus. All the algorithms presented here have execution time O((n+ g)g), hence are linear when the genus is fixed. This is the extended and revised journal version of a conference paper with the title “Schnyder woods generalized to higher genus triangulated surfaces”, which appeared in the Proceedings of the ACM Symposium on Computational Geometry 2008 (pages 311-319).
منابع مشابه
Schnyder Woods for Higher Genus Triangulated Surfaces, with Applications to Encoding
Schnyder woods are a well-known combinatorial structure for plane triangulations, which yields a decomposition into 3 spanning trees. We extend here definitions and algorithms for Schnyder woods to closed orientable surfaces of arbitrary genus. In particular, we describe a method to traverse a triangulation of genus g and compute a so-called g-Schnyder wood on the way. As an application, we giv...
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