1. TIN Triangulated Irregular Network (TIN) A set of adjacent, non-overlapping triangles computed from irregularly spaced points with x, y coordinates and z values.

2. Surface Concepts Discrete vs. Continuous features –Discrete features; roads, land ownership, –Continuous features; elevation, Rainfall data, Pollution concentration

3. What is a TIN ? Tin data structure based on two basic elements to form a continuous faceted surface. »Points with x,y,z values »Series of edges

4. What is a TIN ? (cont.) The triangles are as equi-angular as possible Ensures that any point on the surface is as close as possible to a node The triangulation is independent of the order the points are processed

5. Components of a TIN Nodes Edges Trangles

6. What is a Lattice ? A surface interpretation of a grid –Equally spaced sample points –Referenced to a common origin –Constant sampling distance in the x and y directions

7. What do TINs Look Like ?

9. TIN in ArcInfo Arc: TINARC Usage: TINARC {POLY | LINE | POINT | HULL} {PERCENT | DEGREE | Z_FACTOR}

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