Terrain generating Objects

In general, the specification and the generation of a terrain model makes use of the following terrain forming objects:

• terrain contour or „contour line“ (see Contour Line)
• height point (see Height Point)
• line of fault (see Line of Fault)

Note

The object „Line of Fault“ is superfluous when generating terrain by triangulation and should, therefore, no longer be used in this case.

Furthermore, all objects having specified the local terrain height in the object‘s geometry may determine the terrain height. This holds for the following object types and their respective geometry options:

• point objects: The option „Ground Height: input of value (m)“ is selected. In this case, the entered value is relevant (see Point-like Objects).
• line and area objects: The option „absolute Height/Ground at every Point“ is selected. In this case, the values specified in column „Ground“ of the geometry table are ​​relevant (see Line-like Objects and Area-like Objects).

However, these objects are relevant when generating the terrain as long as the option „Objects with Ground at every Point influence DTM“ on the „DTM“ tab is activated (see DTM Digital Terrain Model Tab). In this case, the terrain heights of these objects determine the terrain‘s level at this location.

Otherwise these objects, even though an individual terrain height has been specified, will be ignored when generating the terrain model. In this case, the object height results from the sum of the local terrain height and the object‘s relative height. In case an absolute height has been entered for the object, however, the entered local terrain height is ignored.

Example

The height of a point and a line source are specified using the options „Ground Height: input of value (m)“ and „absolute Height/Ground at every Point“.

Option „Objects with Ground at every Point influence DTM“ activated	Option „Objects with Ground at every Point influence DTM“ deactivated
The entered ground height in the object‘s geometry is considered when triangulating the terrain.	The entered ground height in the object‘s geometry is not considered when triangulating the terrain.
blue: point and line source red: triangulated terrain edges (limits: 1000 x 1000 m)	blue: point and line source red: There is just a single terrain edge at a height of 0 m between the corners of the limits (from (x,y)=(0,0) to (1000,1000) m).