Abstract
We study the class of rectilinear polygons, calledX – Y polygons, with horizontal and vertical edges, which are frequently used as building blocks for very large-scale integrated (VLSI) circuit layout and wiring. In the paper we introduce the notion of convexity within the class ofX – Y polygons and present efficient algorithms for computing theX – Y convex hulls of anX – Y polygon and of a set ofX – Y polygons under various conditions. Unlike convex hulls in the Euclidean plane, theX – Y convex hull of a set ofX – Y polygons may not exist. The condition under which theX – Y convex hull exists is given and an algorithm for testing if the given set ofX – Y polygons satisfies the condition is also presented.
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This author's research was supported in part by the National Science Foundation under Grants MCS-8202359 and ECS-8121741.
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Nicholl, T.M., Lee, D.T., Liao, Y.Z. et al. On the X-Y convex hull of a set of X-Y polygons. BIT 23, 456–471 (1983). https://doi.org/10.1007/BF01933620
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DOI: https://doi.org/10.1007/BF01933620