Triangulated Irregular Network (TIN)

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Triangulated Irregular Network(TIN)

• A set of adjacent, non-overlapping triangles
  computed from irregularly spaced points with x, y
  coordinates and z values.

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Surface Concepts

• Discrete vs. Continuous features
• Discrete features
• roads,
• land ownership,
• Continuous features
• elevation,
• Rainfall data,
• Pollution concentration

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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

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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

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Components of a TIN

• Nodes
• Edges
• Trangles

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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

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What do TINs Look Like ?
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TIN in ArcInfo

• Arc TINARC
• Usage TINARC ltin_tingt ltout_tingt
  POLY LINE POINT HULL
• PERCENT DEGREE Z_FACTOR

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• END