3D Terrain Models
Depending on type of use Digital Terrain Models are created for different areas of application in various data format and resolution stages (LOD - Level of Detail).
The following data are used as source material to create a DTM:
- Elevation grid (raster):
laser scanning, aerial photogrammetry (autom./manual)
aerial photogrammetry (interaktive, semi automatic)
aerial photographs - orthophotos
DTM for 3D City Models
Data reduction is very important for the presentation of 3D City Models. Thus from the source points a triangulated net (TIN - Triangulated Irregular Network) will be calculated .
This step reduces the amount of data substantially and accelerates also the visualisation.
Various LODs' can be created by interpolation of different height gradations.