Interactive Scale-dependent multidimensional Point Data Selection using enhanced Polarization Transformation - Advances in Cartography and GIScience - page 405

Table 8 and Fig. 10 show the results of the evaluation of 3D-points using
Voronoi-volumes for calculating the relative local density. The curves in
Fig. 10 increase very similar like for the 2D-points in Fig. 9 .

PRiQt QuPber riB1 2rigiQaO pRiQt r i B2 SeOected pRiQt differeQce

16 16 00046 00018

29 29 00053 00001

252 252 00031 00191

255 255 00059 00034

266 266 00023 00001

273 273 00009 00004

378 378 00058 00073

Table 8: Relative local density of points before and after generalization for 3D-points

Figure 10: Curve of relative local density change of kept points (3D) before (green)
and after (blue) generalization

4- Conclusion and future plans

Diverse fields such as Web mapping, Geo-visualization or topographic and
thematic cartography all need to consider a most faithful and recognizable
representation of the real world by different map objects at different scales.
In our work we developed an interactive scale-dependent generalization
tool for selecting/eliminating multidimensional points while preserving
global as well as local characteristics of the spatial distributions.