Terrain Trees library: a tool for efficient and scalable terrain mesh processing

Terrain Trees Library (TTL) is a library for terrain analysis based on a new scalable data structure named Terrain trees. Terrain trees are a new in-core family of spatial indexes for the representation and analysis of Triangulated Irregular Networks (TINs). TTL contains a kernel for connectivity and spatial queries, and modules for extracting morphological features, including edge and triangle slopes, roughness, curvature. It also contains modules for extracting topological structures, like critical point, critical net, watershed segmentation, based on the discrete Morse gradient, and a technique for multivariate data visualization, which enables the analysis of multiple scalar fields defined on the same terrain. In addition to analysis operators, TTL includes a module for efficient topology-aware TIN simplification. It can reduce the size of a TIN while maintaining the topology of the underlying terrain. A parallel version of the simplification algorithm based on OpenMP is also included in TTL. The source code and additional information can be found on GitHub.
(1) Terrain trees: a framework for representing, analyzing and visualizing triangulated terrains by Riccardo Fellegara, Federico Iuricich, Yunting Song, and Leila De Floriani in GeoInformatica (preprint), 2022.
(2) Efficient topology-aware simplification of large triangulated terrains by Yunting Song, Riccardo Fellegara, Federico Iuricich, and Leila De Floriani, Proceedings of the 29th International Conference on Advances in Geographic Information Systems, pages 576–587, 2021.