Abstract:
This paper proposes a multi-resolution TIN surface modeling and visualization method for coastal topography in a virtual globe system. a tile-pyramid model is used to organize the multi-resolution TIN data to solve the problems stemming from the storage of large-scale reference TIN data. A greedy insertion algorithm was used to construct the multi-resolution TIN pyramid. In order to efficiently index the global TIN data, we also propose a novel virtual node (VN) model to guarantee the seamless partition of the multi-resolution TIN triangulation into tiles and storage in a chunked TIN pyramid. Aiming to avoid terrain cracks, we also developed an encoding and decoding approach to match triangulation of different resolutions. Our method was implemented in a virtual globe system. The results show that, the method can dramatically reduce the amount of triangles for rendering the ocean surface, while achieving high fidelity in representation of the islands and coastal lands. This approach overcomes deficiencies of the traditional Grid-based virtual globes.