In plan view I have created my plot plan using the CAD tools. How do I convert this polyline into a terrain perimeter?
Closed polylines can be converted into a terrain perimeter by using the Convert Polyline dialog.
To convert a polyline into a terrain perimeter
If you already have an existing polyline in the .plan file that you want to convert, use the Select Objects tool to select it, then click on the Convert Polyline edit tool.
Note: The polyline you want to convert to a terrain perimeter must be a closed polyline. If you do not already have a closed polyline in your plan to convert, then you need to create one by either selecting CAD> Boxes> Rectangular Polyline and modifying it using the Change Line/Arc and Break Line edit tools, or use the other CAD tools, such as Lines and Arcs to create one.
In the Convert Polyline dialog, select the radio button beside Terrain Perimeter and click OK.
Note: If the Terrain Perimeter choice appears in gray, and cannot be selected, then you either already have a terrain perimeter in your drawing or you do not have a closed polyline selected. Since only one terrain perimeter can be placed in a drawing, you must delete the existing terrain perimeter before you can convert a polyline into a new terrain perimeter.
After you click the OK button the Terrain Specification dialog will display, where you will be able to change the specifications for your terrain to suit your needs for this particular drawing.
Click the OK button once you are finished, then take a Full Overview view to see your Terrain in 3D.