Representation and Visualization of Terrain Surfacesat Variable

We present a new approach for managing the multiresolution representation of discrete topographic surfaces. A Triangulated Irregular Network (TIN) representing the surface is built from sampled data by iteratively reening an initial triangulation that covers the whole domain. The reenement process generates triangulations of the domain corresponding to increasingly ner approximations of the surface. Such triangulations are embedded into a structure in a three dimensional space. The resulting representation scheme encodes all intermediate representations that were generated during reenement. We propose a data structure and traversal algorithms that are oriented to the eecient extraction of approximated terrain models with an arbitrary precision, either constant or variable over the domain.