Triangulated irregular network
In
The vertices of these triangles are created from field recorded spot elevations through a variety of means including surveying through conventional techniques, Global Positioning System Real-Time Kinematic (GPS RTK), photogrammetry, or some other means. Associated with three-dimensional data and topography, TINs are useful for the description and analysis of general horizontal distributions and relationships.
Digital TIN
A TIN comprises a triangular network of vertices, known as mass points, with associated
A TIN used to represent
TIN are based on a Delaunay triangulation or constrained Delaunay. Delaunay conforming triangulations are recommended over constrained triangulations. This is because the resulting TINs are likely to contain fewer long, skinny triangles, which are undesirable for surface analysis. Additionally, natural neighbor interpolation and Thiessen (Voronoi) polygon generation can only be performed on Delaunay conforming triangulations. A constrained Delaunay triangulation can be considered when you need to explicitly define certain edges that are guaranteed not to be modified (that is, split into multiple edges) by the triangulator. Constrained Delaunay triangulations are also useful for minimizing the size of a TIN, since they have fewer nodes and triangles where breaklines are not densified.
The TIN model was developed in the early 1970s as a simple way to build a surface from a set of irregularly spaced points. The first triangulated irregular network program for GIS was written by W. Randolph Franklin, under the direction of David Douglas and Thomas Peucker (Poiker), at Canada's Simon Fraser University, in 1973.[2]
File formats
A variety of different file formats exist for saving TIN information, including Esri TIN, along with others such as AquaVeo[3] and ICEM CFD.[4]
References
- ^ [1]Also known as a "Triangular Irregular Network"
- ^ Franklin, W. R. (1973). Triangulated irregular network program.
- ^ "TIN Files - XMS Wiki".
- ^ "[ICEM] Import geometry from solidworks -- CFD Online Discussion Forums".