This chapter reviews recent development in terrain generalisation. We
focus on issues of aesthetics and legibility in the application of cartographic
generalisation. Generalisation methods are relevant to traditional terrain representations
(spot heights, contours, hypsometric colours, shaded relief) and to grid
and triangulated surface generalisation. First we consider issues related to relief
representation at different scales. As generalisation requires knowledge about the
terrain morphology, several approaches focusing on the classification of terrain
features according to morphometric or topological criteria have been developed.
Cartographic generalisation methods are reviewed with consideration given to
conflicts between terrain representations and other object type data on the map. In
the second part of this chapter, three case studies illustrating previous developments
are presented. First, a generalisation method for hypsometric map production
is described where important valleys and mountain ridges are accentuated to
improve their representation. Second, a method selecting features represented by
isobaths and answering specific constraints of nautical charts is presented. The
third case study is a generalisation method which models the relationship between
terrain and other objects such as buildings and rivers.
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