Qualitative spatial reasoning from the observer's point of view-towards a generalization of symbolic projection

Abstract

Qualitative spatial reasoning is normally concerned with various methods for reasoning in images that in many cases are symbolic, like for instance, maps. The goal is to identify complex object relations by means of methods operating on a high abstraction level. Several approaches to spatial reasoning have been proposed and one such method is symbolic projection which is a qualitative reasoning technique. The method that will be discussed here is an extension of symbolic projection that specifically is concerned with the observer's point of view. In other words, the work presented here is concerned with qualitative spatial reasoning for determination of, among other things, directions, distances and other object relations seen from the observer's perspective, i.e. the projections are in the majority of cases concerned with a singular point. Furthermore, it will also be demonstrated that the slope projections introduced in this paper are a generalization of the original approach of symbolic projection.