Importing Terrain Data from Autocad .dwg file

[Larry Kumpost]

This is what i have done in the past:

I like to keep the imported lines as CAD lines to display the existing topography as dashed lines so what I do is make a copy and change the copy to Terrain elevation lines.

First you must have a terrain perimeter generated to be able to convert them.

I select all the lines, do a copy in place and the copy will be the current selection so open the DBX and change them to the "Terrain, Elevation Data" layer and while still all selected use the "Convert Polyline" tool (bottom pop up toolbar) and select "Elevation Line".

I think when you convert them to elevation lines they automatically are reassigned to the correct layer but I like to get the copy to a different layer before I start converting them and assigning heights.

You will need to select individual lines to set the height (elevation) of each line so turn off the other layer with the original topo lines and/or lock that layer. Generally you should be able to keep the original "existing" topo lines locked.

As an alternative, after making a copy and assigning that to a different layer then locking the original layer, you can select and convert the lines individually adding the heights as you go. If you have more then one topo line at the same elevation you can group (shift) select and convert them at the same time.

[lbuttery]

also, the recommendation is fewer elevation rather than overdoing it

you can "overwhelm" the terrain generator with too much info

give just enough lines to get the job done

Lew