Global Mapper v25.0

Creating features at fixed height above terrain, export to kmz

Is there a quick way to create line or area features with its vertices at a fixed distance above the terrain? I suppose you can export the features in csv format, add a fixed amount to the elevation attribute of each vertex and re-import into GM, but this would require the process to be repeated whenever a change is made to the feature.

Ideally this function would work like the Apply Elevations from Terrain Layer to Selected Feature(s) function, but would prompt the user for the required fixed height above the terrain. This would also have to be repeated if the feature is changed, but would be much quicker that the csv option. The fact that you can draw 3D lines above the terrain when exporting kmz files suggests this function may already exist, but I have not been able to find it.

Currently I am performing this operation in Google Earth after exporting from GM, but that requires each feature to be processed individually.

Any feedback will be appreciated.

Using GM v15.2


  • bmg_bob
    bmg_bob Global Mapper Programmer
    Answer ✓
    The quickest way to create line or area features at a fixed distance above the terrain is to temporarily change the DEM values using the Alter Elevation Values tab on the Elevation Options window (Overlay Control Center, click Options... button).  Add an elevation offset to your DEM before you use Apply Elevations from Terrain Layer to Selected Feature(s), and remove the offset afterwards.
  • Thank you for the tip Bob, definitely quicker than exporting csv.