Terrain map resolution

Studies of land combat processes usually deal with interactions between combatants on (and above) specified terrain. When this involves modeling through computer simulation (or even tracking units in a field test over actual terrain), the terrain is usually represented as a digital terrain map for computational purposes. With a digital terrain map, the terrain surface is represented as a simple surface (often a step function) over a two-dimensional domain covered by a tesselation of squares or hexagons. As the size of the underlying units (let us assume squares) in the domain is reduced, the resolution of the map increases, but the computational cost of preparing, storing and using the map increases exponentially. Thus, there is a question of how high the resolution needs to be for a given application. We study this question from the point of view of accuracy of intervisibility calculations as a function of terrain resolution. proach involves computation of theoretical total intervisibility with varying levels of terrain resolution over simple “pseudo terrains” having assumed mathematical forms. It is found that intervisibility approximations based on digital terrain rapidly approach the theoretical limiting intervisibility as resolution is increased. Relationships between intervisibility surfaces and current military doctrine concerning location of defending forces at the “military crest” are discussed.