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ABSTRACT The Doubly Connected Edge List (DCEL) is an edge-list structure that has been widely utilized in spatial applications for planar topological computations. An important operation is the overlay which combines the DCELs of two input layers and can easily support spatial queries like the intersection, union and difference between these layers. However, existing sequential implementations for computing the overlay do not scale and fail to complete for large datasets (for example the US census tracks). In this paper we propose a distributed and scalable way to compute the overlay operation and its related supported queries. We address the issues involved in efficiently distributing the overlay operator and over various optimizations that improve performance. Our scalable solution can compute the overlay of very large real datasets (32M edges) in few minutes.
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This content will become publicly available on July 1, 2026
On scalable DCEL overlay operations
Abstract The Doubly Connected Edge List (DCEL) is an edge-list structure widely used in spatial applications, primarily for planar topological and geometric computations. However, it is also applicable to various types of data, including 3D models and geographic data. An essential operation is theoverlay operation, which combines the DCELs of two input polygon layers and can easily support spatial queries on polygons like the intersection, union, and difference between these layers. However, existing techniques for spatial overlay operations suffer from two main limitations. First, they fail to handle many large datasets practically used in real applications. Second, they cannot handle arbitrary spatial lines that practically form polygons, e.g., city blocks, but they are given as a set of scattered lines. This work proposes a distributed and scalable way to compute the overlay operation and its related supported queries. Our operations also support arbitrary spatial lines through a scalable polygonization process. We address the issues of efficiently distributing the lines and overlay operators and offer various optimizations that improve performance. Our experiments demonstrate that the proposed scalable solution can efficiently compute the overlay of large real datasets.
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- PAR ID:
- 10658838
- Publisher / Repository:
- Springer
- Date Published:
- Journal Name:
- GeoInformatica
- Volume:
- 29
- Issue:
- 3
- ISSN:
- 1384-6175
- Page Range / eLocation ID:
- 751 to 788
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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