A compact terrain model based on critical topographical features

A broad range of applications, from military programs to survey and land use sys tems, rely on Digital Terrain Models (DTMs) for timely and accurate information. As more and more applications make use of this data, demands for both greater land coverage and finer, more accurate details are on the increase. Meeting these requirements can result in vast volumes of data which strain the memory limits of a computer system. Large digital elevation models can also create a bottleneck in the input/output processes and 3-D perspective rendering algorithms. Therefore, algorithms that generate compact and accurate elevation models are an important topic for research. We present one such algorithm here. This paper describes a triangulation method which builds a DTM from a series of critical line features such as elevation contours, ridge and valley lines, and other breaklines. The method described is an improvement over current techniques because it triangulates any set of critical lines without human intervention, retains the original lines in the triangulation, adds no more than four points to the data, and runs relatively fast. Implementation results are given at the conclu sion of the paper