8

534 Chapter 12: Animation
Note:
In the Object Properties dialog, Rendering
Cont rol must be set to By Object in order to
keyframe the Visibility using the spinner.
Note: Right-clickoveranobjectintheviewports
and select Properties to display the Object
Properties dialog.
Wa rn in g : An object without mapping coordinates
that is invisible at frame 0 will not ask for UVW Map
coordinates at render time. The warning will display at
the frame that the objec t b ecomes visible. This can stop
a render midway, so make sure invisible objects at the
beginning of your animation have mapping coordinates
if necessary.
On and O f f Vi si bil it y
When you first assign a visibility track to an
object, a Bezier float controller is automatically
assigned; this allows gradual visibility. You can
make an object appear or disappear suddenly by
changing the interpolation of the visibility keys to
Step tangency.
Va r i a b l e opa c i t y i s s u p p or ted i n t h e s h a d e d
viewports. For ease of use, the object never
completely disappears from the viewports.
Visibility Inheritance
An object can inherit the visibility of its parent
(as determined by the parent’s Visibility track
intheTrackView).UsetheObjectProperties>
Inherit Visibility check box to specify the visibility
inheritance of an object.
Groups and V isibility
All members of a Group inherit the visibility of
the parent when a visibility controller is assi gned
to the parent. Transparent materials and hidden
objects have no effect on this function.
Level of Detail Utilit y and Visibility
The Level of Detail utility (page 1–1255) lets
you construct an object that alters its geometric
complexity or level of detail based on its size in the
rendered image. You create several versions of the
same object each with different levels of detail; you
group them as one, and then assign the Level of
Detail utility. This automatically creates a special
LOD controller as a Visibility track.
Procedures
To add a visibility tr ack to objects:
1.
In Track View Curve Editor or Dope Sheet Edit
Keys mode, highlig ht the object you want to
affect in the Hierarchy list on the controller
window.
2. From the Track View > Tracks menu, choose
Visibility T racks > Add.
3. Select the keys then use Cont roller > Properties
to adjust the key va lues and interpolation.
A value of 0 creates an invisible object, a value
of 1.0 creates a fully visible object. Change
the interpolation to step for sudden visibility,
rather than gradual fades.
A visibility track appears below the selected
object(s). Add and edit keys in the visibility track
to control the object’s visibility.
To add v isibility k eys:
1.
Once you have a visibility tr ack assigned to the
object, highlight the track.
2. On the toolbar, click Add Keys.
3. On the Track View Key w indow, click in a
visibilit y track to add a key at that time location.
Example: To create and animate a visibility track
using the Obj ect Proper ti es dia log:
1.
Create a box.