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| Content Provider | Society for Industrial and Applied Mathematics (SIAM) |
|---|---|
| Author | Franzblau, D. S. |
| Copyright Year | 1989 |
| Abstract | Finding the minimum number of rectangles required to cover a rectilinear or orthogonal polygon, where overlapping of rectangles is allowed, is one of several well-known, hard geometric decomposition problems. This paper reports the first results known that give worst-case performance bounds for an approximation algorithm for this problem. It is proved that partitioning the polygon into rectangles (with no overlapping) produces at most $2\theta + h - 1$ rectangles, where $\theta $ is the minimum number of rectangles in a cover, and h is the number of holes. Examples are also given in which this bound is tight. The proof is based on counting arguments, and on Eulers formula for a planar graph. This paper shows that extending rectangles vertically and deleting duplicates produces at most $O(\theta \log \theta )$ rectangles. For the proof, geometric constraints are used to construct a large an-tirectangle, a set of points with no two contained in the same rectangle. This algorithm has an $O(n\log n)$ implementation using balanced trees, where n is the number of vertices. |
| Starting Page | 307 |
| Ending Page | 321 |
| Page Count | 15 |
| File Format | |
| ISSN | 08954801 |
| DOI | 10.1137/0402027 |
| e-ISSN | 10957146 |
| Journal | SIAM Journal on Discrete Mathematics (SJDMEC) |
| Issue Number | 3 |
| Volume Number | 2 |
| Language | English |
| Publisher | Society for Industrial and Applied Mathematics |
| Publisher Date | 2006-08-08 |
| Access Restriction | Subscribed |
| Subject Keyword | approximation Polyominoes heuristic rectilinear cover sweep-line orthogonal Analysis of algorithms and problem complexity polygon Packing and covering rectangle Combinatorics algorithm |
| Content Type | Text |
| Resource Type | Article |
| Subject | Mathematics |
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