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Display Backgrounds and Shadows
The visual style also controls the display of backgrounds and shadows in the
viewport.
Backgrounds
You can use a color, a gradient fill, an image, or the sun & sky as a background
in the viewport in any 3D visual style, even one that does not shade objects.
When Background is set to On in the current visual style, the background is
displayed.
To use a background, you first create a named view with a background and
set the named view as current in the viewport.
Shadows
Shaded objects in a viewport can display shadows. Ground shadows are
shadows that objects cast on the ground. Mapped object shadows are shadows
cast by objects onto other objects. The lighting in the viewport must be from
user-created lights or the sun for mapped object shadows to be displayed.
Where shadows overlap, they appear darker.
NOTE To display mapped object shadows, hardware acceleration is required.
When Enhanced 3D Performance is off, mapped object shadows cannot be
displayed. (To access these settings, enter 3dconfig at the Command prompt. In
the Adaptive Degradation and Performance Tuning dialog box, click Manual Tune.)
Displaying shadows can slow performance. You can turn off shadows in the
current visual style while you work and turn them back on when you need
them.
In the Properties palette, you can set the Shadow Display property for an
object: casts shadows, receives shadows, casts and receives shadows, or ignores
shadows.
More options are available for shadows used in rendering.
304 | Chapter 10 Change Views