Abstract
Given P and P′, equally sized planar point sets in general position, we call a bijection from P to P′ crossing-preserving if crossings of connecting segments in P are preserved in P′ (extra crossings may occur in P′). If such a mapping exists, we say that P′ crossing-dominates P, and if such a mapping exists in both directions, P and P′ are called crossing-equivalent. The relation is transitive, and we have a partial order on the obtained equivalence classes (called crossing types or x-types). Point sets of equal order type are clearly crossing-equivalent, but not vice versa. Thus, x-types are a coarser classification than order types. (We will see, though, that a collapse of different order types to one x-type occurs for sets with triangular convex hull only.) We argue that either the maximal or the minimal x-types are sufficient for answering many combinatorial (existential or extremal) questions on planar point sets. Motivated by this we consider basic properties of the relation. We characterize order types crossing-dominated by points in convex position. Further, we give a full characterization of minimal and maximal abstract order types. Based on that, we provide a polynomial-time algorithm to check whether a point set crossing-dominates another. Moreover, we generate all maximal and minimal x-types for small numbers of points.
Originalsprache | englisch |
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Titel | 31st International Symposium on Computational Geometry, SoCG 2015 |
Herausgeber (Verlag) | Schloss Dagstuhl - Leibniz-Zentrum für Informatik |
Seiten | 285-299 |
Seitenumfang | 15 |
Band | 34 |
ISBN (elektronisch) | 9783939897835 |
DOIs | |
Publikationsstatus | Veröffentlicht - 1 Juni 2015 |
Veranstaltung | 31st International Symposium on Computational Geometry: SoCG 2015 - Eindhoven, Niederlande Dauer: 22 Juni 2015 → 25 Juni 2015 |
Konferenz
Konferenz | 31st International Symposium on Computational Geometry |
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Kurztitel | SoCG 2015 |
Land/Gebiet | Niederlande |
Ort | Eindhoven |
Zeitraum | 22/06/15 → 25/06/15 |
ASJC Scopus subject areas
- Software