EuroSDR Projects - Host Ireland

Normal: Manual task of the operator
Italic: Task of the operator that is supported by task specific tools
Bold: Automatically performed task
3.1.2.11 University of Aalborg
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Table 3-2: Block diagram of Delft processing strategy
The modelling of buildings was carried out by three university students as part of their studies
(Frederiksen et al., 2004). The applied method used laser scanner and 2D vector map data to extract
and model the buildings. The applied method can be used to model rectangular buildings with gable
roofs and rectangular buildings with gable roofs in different levels, see Figure 3-21.
Figure 3-21: Types of buildings to be modelled.
A 2D vector map is used to extract the data within the buildings and the 2D vector map is also used as
building outline.
After the extraction of the data, the data is interpolated into a rectangular grid. For every point in the
grid, a surface normal based on the point and its neighbouring points are calculated (see Burrough and
McDonnell, 1998, p. 190-192). Now all points belonging to a roof plane have to be found. An