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Selecting an Elevation Field in Breakline Source Layers


About Selecting an Elevation Field

The elevation field determines the source of Z values used when retrieving the features from a breakline source. The elevation field can either be the "Shape" field where the Z coordinate of each vertex is used as the elevation, or from a standard field. If a standard field is used, one elevation (i.e., the attribute value for the feature) is used for the entire feature geometry.

Note: If the "Shape" field is not listed for a layer, the layer is not 3D geometry.

Learn more about creating 3D geometry using LIDAR data

The "Shape" field is typically used for breaklines such as stream centerlines where the ability to use Z values for each vertex is paramount. On the other hand, features such as ponds or lakes do not require a detailed resolution of Z values for each vertex and can be described using a single elevation from a field in the database.

Example of using a "Shape" and standard field

Streams (red) use the "Shape" field and the pond (yellow) uses a standard field (MinZ) Selected Elevation fields in the source list
When used in combination with a type field, more than one elevation field can be used within a single layer. For example, a polygon layer may store both river and pond features. You would like to use a single elevation for the ponds, but use the Z values on each vertex for the rivers. This can be achieved by selecting a type field and choosing the elevation field for the pond type value, and the "Shape" field for the river type value.

Example of using a "Shape" and standard field within the same layer

Rivers use the "Shape" field and the ponds use a standard field (MinZ) Selected Elevation fields in the source list

How to Select an Elevation Field

  1. Click within the Elevation Field Column for the row of the layer you wish to select an elevation field for.

  2. Select a field from the list.