  Mapping is an important part of many robotic applications. In order to
measure the performance of the mapping process we have to measure the quality
of its result: the map. The map is essential for robotic algorithms like
localization and path planning. Previously it was shown how matched Topology
Graphs can be used for map evaluation by comparing the topology of the robot
generated map to the topology of a ground truth map. In this paper we are
extending the previous work by detecting open areas, for example rooms, in the
2D grid map and adding those to the topological representation. This way we can
avoid the unreliable generation of paths in open areas, thus making the
Topology Graph generation, and through that also the Topology Graph matching,
more stable and robust. The detection applies the alpha shape algorithm for
room detection.
