TOPGIS - Swisstopo’s production system for 3D topographic databases

Abstract

To truly visualize topographic data in 3D requires truly 3D topographic databases. The Swiss Federal Office of Topography (swisstopo) is replacing their current map-based 2D VECTOR25 dataset with a 3D Topographic Landscape Model (TLM). This represents a major shift in their internal production workflow, and also a beneficial change for their customers who require accurate 3D geographical reference data. The TLM is swisstopo’s new vector landscape model. It will be very upto- date across all of Switzerland, seamless across this area, 3D, and very accurate with better than 1 meter accuracy in all three dimensions. The TLM forms the basis for several geo-data products and the Swiss National Map series. The TLM is accompanied by a new Digital Terrain Model (DTM) which is designed to be consistent at all times with the TLM. The DTM is derived principally from LIDAR (Light Detection and Ranging) data. For the capture and administration of the TLM and the DTM, a new high-performance infrastructure called Topographic Geographic Information System (TOPGIS) has been built for swisstopo by ESRI Switzerland. As the central production infastructure for the TLM, TOPGIS is a modern, database-centered system for data capture, editing, management and storage. The TLM and DTM are photogrammetrically updated based on high resolution digital imagery. TOPGIS supports three simultaneous modes for producing 3D data: ∙Stereo-photogrammetric 3D TLM production ∙ Stereo-photogrammetric DTM production ∙ TLM production by using mono-plotting from orthophotos and the DTM.