Terrain Data

Terrain Data Overview

A terrain profile consists of a table of distances and elevations along the great circle arc between two sites. On most practical paths less than 150 kilometers, the difference between a straight line and the great circle arc is negligible. The Terrain Data module is used to create a terrain profile using any of the following methods:

  • Elevations are read from a terrain database.
  • Manual entry of distances and elevations taken from topographic maps.
  • Direct entry of distance - elevation data from topographic maps using a digitizing tablet.
  • Conversion of distance - elevation data in text files from other sources.

Optional structures and ranges can be added to the path. The display consists of the data entry form at the top and the profile display at the bottom. Once the second point has been entered, the profile will be drawn and will be continually updated as the data entry proceeds.

To move to a specific point on the profile, click on the profile display. The first point past the mouse cursor will be selected. Alternately, you can click on a line in the terrain data entry form.

The Home, End, PgUp, PgDn keys, the up and down cursor keys and the vertical scroll bar are used to move through the profile.