More than 15 years ago, a set of qualitative spatial relations between
oriented straight line segments (dipoles) was suggested by Schlieder.
However, it turned out to be difficult to establish a sound
constraint calculus based on these relations.
In this paper, we present the results of a new investigation into dipole
constraint calculi which uses algebraic methods to derive
sound results on the composition of relations
of dipole calculi.
This new method, which we call condensed semantics, is based on
an abstract symbolic model of a specific fragment of our domain.
It is based on the fact that qualitative dipole relations
are invariant under orientation preserving affine transformations.
The dipole calculi allow for a straightforward representation of
prototypical reasoning tasks for spatial agents.
As an example, we show how to generate survey knowledge from local observations in a
street network. The example illustrates the fast constraint-based reasoning capabilities
of dipole calculi. We integrate our results into two reasoning
tools which are publicly available.