A multi-agent System Approach for Featuredriven Generalization of isobathymetric Line - Advances in Cartography and GIScience - page 492

4.3 Preliminary results
The data structure has been developed and tested on a set of isobaths from
a nautical chart of a coastal area ( Figure 11 ) . The map is at scale 1:12500.
Isobath depths are -2, 0, 2 meters and every five meters from 5 to 25
meters. The first step of the work consisted in extracting features and
building the feature tree ( Figure 11 ).
Figure 11: Isobath map with its corresponding feature tree. Grey nodes are peaks, black
nodes are pits
Depending on the type of features, features can be removed if they do not
satisfy the legibility constraint. Current result with the simplified map and
its feature tree is shown on Figure 12 . Small contours located in the chan-
nel have been removed by removing the features. The feature tree has been
simplified at the same time as the number of levels has been reduced: a
peak that contained only one peak has been removed to maintain consis-
tency of the tree structure.
Figure 12: Simplified map with its corresponding feature tree. Grey nodes are peaks, black
nodes are pits.