Geoscience Reference
In-Depth Information
Our enhanced Polarization Transformation (PT) approach works with large
point data sets and is suitable for real-time generalization of points in Web
maps because of its computing simplicity. Through its interactive use the
user can define either the number of points to be kept or the target map
scale. The evaluation verified the similarity of point distribution and den-
sity before and after the point selection. In this work an existing evaluation
method for point selection in 2D based on Voronoi areas was extended for
points in 3D using Voronoi volumes.
A next step within point generalization using our enhanced PT-approach
should be to apply the adequate point symbol size to the kept points appro-
priate to the target scale. In further research we will also include semantic
attributes in our enhanced PT algorithm. Another planned further investi-
gation will be an interactive combination of point selection and aggrega-
tion (clustering) using the PT-method and as well a comparison with other
point selection methods.
Acknowledgement
The authors gratefully acknowledge Deutsche Flugsicherung GmbH for providing the data and
the support of the TUM Graduate School at Technische Universität München, Germany.
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