Ensuring the Semantic Correctness of Complex Regions

Abstract. Ensuring the semantic and topological correctness of spatial data is an important requirement in geographical information systems and spatial database systems in order to preserve spatial data quality and enable correct operation execution. Spatial objects like complex regions are usually represented as an ordered sequence of segments (sequence view) to support and ease the computation of spatial operations by means of plane sweep algorithms. The semantic correctness of such a sequence is usually simply assumed but is not easy to see. In this paper, we present a novel and efficient algorithm to discover the cyclic structure and check for the semantic correctness of the sequence representation of a complex region by determining its cyclic structures (component view) in terms of multiple faces possibly containing holes. The algorithm producing the component view is also interesting for object construction, manipulation, and visualization.