Practicable photogrammetry for 3D-GIS

Encouragement for 3D-GIS comes from advances in technology and evolving user needs to cope with increasingly complex spatial analysis tasks. The demand for spatial information is most pressing in urban areas. The present paper elaborates on how current photogrammetric means can be used for 3D topographic mapping for municipal information systems. Aiming at comprehensive spatial 3D operation we rely on a data model that is based on 3D-FDS. Beside the basic issue of adequate data modelling and providing tools for analysis and visualization, efficient data acquisition is in fact the major challenge from the point of view of costs of creating a 3D-GIS. Even without automated information extraction from images, aerial and terrestrial photogrammetry offer solutions to both geometric object reconstruction and texture mapping. For testing the applicability of concepts and available tools we have built a prototype 3D-GIS. We also report our experiences with regard to the developed procedures and make suggestions for further development of photogrammetric means.