I present an experimental study of a new algorithm that synthesizes separate programs, for fast viewshed, and for fast approximate visibility index determination, into a working testbed for quickly siting multiple observers jointly to cover terrain from a full level-1 DEM.

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Context

Several year project in studying terrain elevations. Previous results:

• Triangulated Irregular Network I can TIN all points of a level-1 DEM in about a minute on this laptop.
• Triangulated compression Triangulated compression Triangulated compression Triangulated compression Triangulated compression Triangulated compression
  of can TIN all points of a
• Lossless and lossy compression of gridded elevation databases.
• Interpolation from contours to grid.
• Observer Siting

PhDs generated:

• Clark K. Ray, Representing Visibility for Siting Problems, 1994. (now at US Military Academy, West Point)

• Michael B Gousie, Contours to Digital Elevation Models: Grid-based Surface Reconstruction Methods, 1998. (Wheaton College)

• Helio Pedrini, An Adaptive Method for Terrain Surface Approximation Based on Triangular Meshes , 2000. (Universidade Federale do Paraná)

Elevation vs visibility	Lossy compression