2.0

Chapter 4 Working with Cross Sections
254
To set the current surface
1 From the Cross Sections menu, choose Surfaces ä Set Current Surface to display
the Select Surface dialog box.
2 Do one of the following to filter the listed surfaces:
n
Select Terrain Surface to show the terrain surfaces in the list.
n
Select Volume Surface to show the volume surfaces in the list.
3 Select the surface that you want to make current.
4 Click OK.
Sampling Existing Ground Section Data with and
without Multiple Surfaces
To sample existing ground data for cross sections from multiple surfaces, use the
Toggle Multiple Surfaces command to enable the use of multiple surfaces. If you
subsequently want to sample data for only one surface, then use the Toggle
Multiple Surfaces command to disable the use of multiple surfaces.
If multiple surfaces are on, then the Sample From Surface command uses all the
surface names in the surfaces.txt file created by the Select Multiple Surfaces
command. Each surface is used for each defined section. The command extracts
elevations for the section from the surface associated with each surface name in
the file. If multiple surfaces are off, then the Sample From Surface command
does not use the surfaces.txt file. The current surface is sampled instead.
To select between using one or several surfaces to sample cross section data
n
From the Cross Sections menu, choose Surfaces ä Toggle Multiple Surfaces.
A prompt is displayed that states that multiple surfaces are on or off.