About Extracting Surface Data

You can extract AutoCAD entities from an AutoCAD Civil 3D surface.

Extracting individual components from a surface enables you to manipulate these components without exploding the surface object. The surface data available to extract is based on the display properties of the selected surface.

Note: The extracted objects preserve the properties set in the current surface style.

The following table lists the extracted objects for each type of surface components.

Surface component ...	Is extracted as ...
Points (2D and 3D)	Point objects
Triangles (2D and 3D)	3D face objects
Border (2D)	POLYLINE object LWPOLYLINE object (if the Borders Display Mode is set to Flatten to Elevation)
Border (3D)	POLYLINE object LWPOLYLINE object (if the Border Display Mode is set to Flatten to Elevation) 3D face object (if Use Datum and Project Grid to Datum are set to true)
Major Contour (2D and 3D)	LWPOLYLINE object
Minor Contour (2D and 3D)	LWPOLYLINE object
User Contours (2D and 3D)	LWPOLYLINE object
Gridded (2D and 3D)	POLYLINE object (if the Borders Display Mode is set to Use Surface Elevation LWPOLYLINE object (if the Border Display Mode is set to Flatten to Elevation)
Directions (2D and 3D)	The type of object depends on the surface style settings. See To Create a Surface Style.
Elevations (2D and 3D)
Slopes (2D and 3D)
Slope Arrows (2D and 3D)
Watersheds (2D and 3D)

Tutorial Exercise: Extracting Objects from a Surface