Create a Surface
Certain types of objects in your data can be used to define a surface, including:
- Points (surveyed, CAD, and lightweight)
- Lines (CAD lines, polylines, linestrings, breaklines)
- Alignments
- Sessions and vectors (this is unusual)
When you create a surface, you select a set of these objects. These selected objects are called "members" of the surface. Members do not become part of the surface, they simply define it. The surface is created as a separate object. To change a surface, you add, remove, or edit the positions of members in the set. As a result, the surface object updates to reflect the changes.
Note: Before creating a surface, set the default Maximum Edge Length and the Maximum Edge Angle of surfaces in Project Settings. Select Project Settings in the Quick Access Toolbar. Then click Computational Settings and Surface in the Project Settings dialog. Setting these can reduce the amount of trimming needed on the surface edge.
Tip: You can import points as a surface in the Import Format Editor.
Prerequisites:
- 3D points, lines, or alignments (with elevations)
To create a surface:
- Do one of the following:
- Select Create Surface in Surfaces > Create.
- Right-click Surfaces in the Project Explorer, and select Create Surface.
The Create Surface command pane displays.
- Type a name in the Name box.
- Select a type in the Surface Classification list. This classification will be used to compare the surface to another surface with a different classification to calculate volumes for the Earthwork Report and other commands.
- In the Color list, select a color for the new surface.
- In the Measured date field, select or enter a date and time specifying when the surface members (objects from which the surface will be built) were surveyed.
- Click in the Members to form surface field and then, in a graphic view or the Project Explorer, pick objects to include as members of the surface, or click for additional selection options.
Note: If a selected feature point, line, and/or polygon (resulting from feature processing) has its Include in surface feature option set to No, a message is displayed beneath the Members to form surface field indicating this and the object will not be included in the new surface. If you want to include this feature object in the surface, you must open its Properties and change the Include in surface option to Yes.
- Click . The surface appears in the graphic views and the Project Explorer.
Note: To see the slope direction of each triangle in a surface, set Slope arrows to Show in the properties for a surface. To specify the length of the slope arrows, select Project > Project Settings. Then click Computations and Surface in the left pane. Change the value in the Slope arrow length box.
Tip: To view surfaces more clearly, use a 3D view, and set your view filter to Surfaces. - Check the surface for quality to make sure it accurately reflects the project topography.
- Add contours and check the surface in the Plan View and 3D View.
- Use the Coordinate scroll to check the elevation at specific locations.
