Scale-dependent rendering in ArcGlobe

Sometimes you only want data from a particular layer to appear in the display when you are within a certain range of it. This is a common and effective way to optimize the performance of an ArcGlobe document and should be used frequently. Using visible distance ranges, you can set when a layer becomes visible in the display. For example, set the distance ranges for local layers with small extents so they're only visible when you zoom in to their proximity.

Distances are used in ArcGlobe, rather than traditional map scales, because a 3D oblique view contains a continuously different map scale between the foreground and background. When copying 2D layers from ArcMap, an approximation is calculated to convert between map scales and distances for the layer visibility ranges. Visible distance range units are in the same units as globe display units set on the General tab of the Globe Properties dialog box.

The distance value used for scale-dependent rendering and reported on the status bar is not the distance of the observer to the surface of the globe. It is better described as a viewport distance. The value is calculated as a combination of the window size and the observer distance, so different values would be returned for the same bookmark if the display window was resized.

Distance-based layer visibility is not available in ArcScene, although you can set layer visibility for navigation purposes only, as an alternative performance optimization.

Steps:

1. In the table of contents, right-click the layer whose visible distance range you want to set and click Properties.
The Layer Properties dialog box appears.
2. Click the Globe General tab.
3. Check the Don't show layer when zoomed option.
4. In the Out beyond box, type the distance at which you want the layer to become invisible when you zoom out.
5. In the In beyond box, type the distance at which you want the layer to become invisible when you zoom in.
6. Optionally, click Check visibility based on each tile distance to enable distance visibility for discrete parts of the layer.

This is the default setting and further improves performance. When this option is on, tiles of data become visible separately when navigating near the distance threshold of a layer.

7. Click OK.

The layer is visible between the two thresholds.

Tip:

• Navigate to key locations in your 3D view and refer to the distance value reported on the status bar when populating the visibility range of a layer.
• You can also set a layer's visibility range by using the current distances in the display. Right-click a layer in the table of contents, point to Visible distance range, and use the Set Maximum Distance and Set Minimum Distance commands to capture distances used in the display.