About setting the role of a 3D layer
Layers can play a variety of roles within the 3D view. They can float independently of other layers, drape on top of a separate 3D surface, or provide surface heights for other layers to drape on.
You can change the category of a layer in ArcGlobe—as an elevation, draped, or floating layer—by using context menu commands. After you categorize a layer, you'll be able to use different options that become available for a layer in that category. ArcGlobe layers are grouped by their category when the table of contents is sorted using the List By Type button.
Elevation layers provide a source of base heights for other layers. Example sources of elevation data include single-band digital elevation model (DEM) rasters, triangulated irregular networks (TINs), and terrain datasets.
In ArcGlobe, you can add one or more elevation data sources that operate as a single seamless surface for all your draped layers. Boundaries between elevation sources are blended together, and the higher-resolution elevation source is automatically used for each geographic region.
Draped layers use other layers as elevation sources. Drape a layer to show it on a 3D surface. For example, you might drape an aerial photo and its associated features on a mountaintop.
Rasters and 2D features are added into ArcGlobe as draped layers by default.
Floating layers are used to show rasters or features that are not placed on the elevation surface. Examples of floating layers include underground or above ground utilities, aircraft, and clouds.
In ArcGlobe, a floating layer is drawn independently of the elevation layers defining the globe surface. You can use offsets or other independent surfaces to define where in 3D space the layer is drawn.
The Elevation tab on the Layer Properties dialog box shows how data will be displayed depending on where the features get their elevation source from. The graphic below is from the Elevation tab will interactively update to reflect the current layer property settings deriving the elevation surface. The highlighted surface will be outlined in red as the selected elevation source. The location of the solid square represents if there are additional elevation values in the layer, or if it has an applied offset. Offsets can be applied to the layer above or below the derived surface elevation values. If there are no feature-based heights the layer will be draped, shown by the solid square in line with the selected surface.
Use the context menu or the What's This function to find out more information about settings on any dialog box or window.