Product(s):	OpenRoads Designer / OpenRail Designer
Version(s):	10.10+
Area:	Terrain Modeling
Original Author:	Bentley Technical Support Group

 
Question: 

What is the difference between the Merge and Append option available while crating the complex terrain model?

Answer:

Merge: The Merge action will discard data from the primary terrain model and only keep the data from the merge model in the overlapping areas.

If you want to replace the data in the overlapping areas with the new data, in that case you can use the merge option. 


Append : The Append action will keep the data from both the terrain models in the overlapping area.

If you want to keep the existing and new data in the overlapping areas, in that case you can use the append option. 

Following diagram explains the difference between the two actions.