Richard FECISKANIN

Simplification methods of surfaces models for georelief modelling by triangulated irregular network

Feciskanin, R.: Simplification methods of surfaces models for georelief modelling by triangulated irregular network. Kartografické listy, 2011, 19, 4 figs., 1 tab., 15 refs.

Abstract: Automatic creation of surfaces or common 3D objects models by simplifying detailed models become increasingly important. It is used for creating models of redundantly dense input data (eg. laser scanning). It plays a key role in the generation of models in various resolutions. Automatic model simplification procedures have a tradition especially in the field of computer graphics. The paper presents the possibility of using these methods for georelief modeling where geometrical accuracy is important – the accuracy of values of partial derivatives and from them derived morphometric parameters. The known algorithms from authors Lindstro-Turk and Garland-Heckbert are analyzed. Models consisted of a triangulated irregular network created by automatic simplification achieve very good accuracy of the derived geometric parameters. This is because the conditions that define the process of simplification of selected algorithms are related to the conditions of correct configuration of triangles with respect to mode-led surface. Therefore the resulting model with lower number of elements (vertices, triangles) sufficiently accurately represents the modeled surface. It is just efficiency of georelief model created by surface simplification with maintaining sufficient accuracy of derived geometric characteristics which is its greatest advantage.

Keywords: georelief modeling, simplification, accuracy, triangulated irregular network