document: Based on the description model of object-orientation-based direction relation in two-dimensional space, the description mode of object-orientation-based direction relation in three-dimensional space is proposed. The basic idea is that the actual direction region is modeled as an open shape. The computation related to the world boundary of spatial direction region is eliminated, and the processing of the direction predicates is converted into the processing of topological operations between open shapes and closed geometry objects. The algorithms of topological operations between open shapes and closed geometry objects are presented and the theoretical proof for the correctness and completeness of the algorithms is performed.
doc_bio_tags: O O O B I O O O O O O O O B I O O O O O O O O O O O O O O O O B I O O O O B I O B O O O B I O O B I O O O O B I I I I O O O O B I I I O B I O O B I O B O O O O B I O O B I O O O O O O O O O O O O O B O O