Incremental Delaunay Triangulation Algorithm for Digital Terrain Modelling

Abstract

One of the problems when storing and computing an elevation data is that the amount of data can be enormous. A Triangulated Irregular Network (TIN) is an altemative to represent an Qlevation by which a TIN can be extracted from a dense grid of data. We present an incremental Delaunay triangulation algorithm for constructing a TIN. The algorithm starts with an initial triangular network covering entire area of an elevation grid. More data points are inserted into a network sequentially by selecting a subset of the grid points; this subset is the most significant contribution to the terrain model. The Delaunay triangulation of this subset is the TIN that approximates the elevation at all grid points within a distant criterion. As a result, the conversion of spatial data structure from an elevation grid to a TIN significantly reduces the number ofdata points to represent the terrain surface. 1.