Triangulated Irregular Networks (TINs)

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Triangulated irregular networks, or TINs, are a vector-based models used to represent surface morphology. Vertices (or points) are triangulated using various interpolation methods and are connected by a series of edges. Unlike raster-based digital elevation models, or DEMs, nodes can be placed irregularly over a surface, which can contribute to finer detail in more elevationally complex areas. The image below represents an area near Big Bear Lake, CA. The slope of each triangle within the TIN is symbolized using graduated colors -- triangles with the greatest slope are shown in dark purple, and triangles with less slop are shown in light purple. The horizontal lines crossing the landscape are contour lines. The white lines represent regular contours, while the blue line represents an index contour. 




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