Spatial relations have been comprehensively used in many applications

such as Spatial Database Query Language

Content-Based Image Retrieval and Similarity of Spatial Scenes

etc. However

because the conventional approaches of describing direction relations can not express direction information effectively when the target object is inside or intersected with minimum boundary rectangle (MBR) of the reference object

which limits the description of concepts related to spatial relations. In this paper

firstly

a detailed direction relations model (DDRM) is proposed

which can describe the information related to the interior of MBR of the reference object. The DDR includes interior

boundary and ring direction relations

and each direction relation is composed of 9 atom directions at most. The interior directions describe some concepts related to the interior of the reference object

The boundary directions deal with some terms related to boundary of the reference object

and the ring directions describe the information about the difference region between the reference object and its MBR. Secondly

after composing topological relations and DDRM

the number of discernible spatial relations about line/region

region/region and point/region increase. Unlike the current direction relations model

the DDRM is sensitive to the shape and the hole of a reference object

and is helpful to improve the ability of describing the spatial relations.