a contouring method of linear interpolation that bases its predicted surface on the flat plane that can be fitted to any three non-collinear points. It assumes that point observations represent exact values and that the sampling has been carried out at sufficient detail to fit a continuous surface.

See digital terrain model -- TIN.

data structure, normally used in connection with terrain modeling, that describes a three-dimensional surface as a series of irregularly shaped triangles.

A data structure used to define a three - dimensional surface as a series of irregular triangles. Used for efficient analysis in terrain modelling because any geographic shape can be accurately represented by the sides of triangles, given that they are sufficiently small. Where large flat areas are to be defined, larger triangles can be used. The tin data set includes topological relationships between points and their neighboring triangles. Each sample point has an x, y coordinate and a surface, or z-value. These points are connected by edges to form a set of non-overlapping triangles used to represent the surface. Tins are also called irregular triangular mesh or irregular triangular surface model.

A representaion of a surface derived from irregularly spaced sample points and breakline features. The TIN data set includes topological relationships between points and their proximal triangles. Each sample point has an x,y coordinate and a surfaceor z value. These points are connected by edges to form a set of non-overlapping triangles that can be used to represent the surface. TIN's are also called irregular triangular mesh or irregular triangular surface models.

DTM points are linked into a series of triangles from which the elevation of any point can be determined. Transparency - An image which is viewed by transmitted light. Specifically a film image, usually positive and often in color, intended for projection.

a data structure which describes a three-dimensional surface as a series of irregularly shaped triangles. Usually used in connection with terrain modeling.

A Triangulated Irregular Network (TIN) is a digital data structure used in a geographic information system (GIS) for the representation of a surface. A TIN is a vector based representation of the physical land surface or sea bottom, made up of irregularly distributed nodes and lines with three dimensional coordinates (x,y, and z) that are arranged in a network of nonoverlapping triangles. TINs are often derived from the elevation data of a rasterized digital elevation model (DEM).