ArcGIS Tutorial: 3D Features

You may want to see the feature data as well as the surface in perspective. However, feature data (shape) and what it can be used to represent are different from surface data. Some GIS features store z-values or height positions in their geometry. This can be used to display features in a 3D view. You can also view two-dimensional feature data (no 3D properties) in 3D mode, for example, by using Extrude or by overlaying features on the elevation surface.

　　Feature geometry

Feature data differs from surface data when it represents a discrete object, not a continuous phenomenon. Also, features typically have shape (geometry) and properties.

Typical feature geometries are point, line, and polygon:

• Point features can represent peaks, telephone poles, or well positions.
• Line features can represent road, river, or ridge lines.
• Polygon features can represent buildings, lakes, or administrative regions.

　　Z-Value

The attributes of a feature can be used to store values about the elevation or height of a feature. Some GIS features store elevation values in their own feature geometries, for example, Pointz features are stored as a set of X, Y, Z coordinates. You can use Z-values in feature geometry or feature attributes to display features in a 3D view.

Sometimes features may be missing elevation or height values. In this case, by overlaying or stretching these features, you can still view them in the 3D view (see the following section).

　　Overlay and Extrude Features

If the area contains a surface model, you can use the values in the model as Z-values for the feature. This is called an overlay feature. Typically, you can also use this method to display image data in 3D mode.

If you want to display building features in 3D mode, you can stretch them based on attributes such as building height or number of floors. You can also stretch according to an arbitrary value.

Sometimes you might want to see 2D features in a 3D view, where Z-values are taken from a non-height value attribute. For example, you might want to create a view based on the population that shows city points that are stretched to cylinders.

Whether you have features that already have 3D geometry or 2D features that do not have z-values defined, you can customize the display of features in 3D mode through the ArcGlobe and ArcScene layer properties.

ArcGIS Tutorial: 3D Features