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The first time you add a behavior to the scene, a new rollout appears for the
behavior below the Setup rollout. This rollout lets you change settings for the
behavior. Certain behaviors, such as Seek and Avoid, let you specify "target"
objects.
TIP Behaviors are assigned generic names by default. It's a good idea to rename
them with more meaningful descriptors; for example, "Seek Ball" or "Avoid Fire".
To display the rollout for a different behavior in the scene, choose it from the
drop-down list in the Behaviors group. To see the controls available in the
rollout for a behavior type, follow the link from its entry in the above list.
In addition to the controls available in behavior rollouts, you can use the
Behavior Assignments and Teams dialog on page 4845 to turn behaviors on and
off (with the Active check box), and for all behaviors except Avoid, Orientation,
and Surface Follow, you can set and animate Weight. The Active status is
animatable for all behaviors.
Using Behaviors
To use a behavior, you apply it to a delegate or a team of delegates using the
Behavior Assignments and Teams dialog on page 4845. In this dialog, each
assignment of a behavior to a delegate is given a weight. You can modify
and/or animate these weights to influence the simulation.
Behavior assignment weights can profoundly effect a simulation. When
applying two or more behaviors to the same delegate, the weights define the
relationship between the behaviors, making one more or less powerful than
the other. One way to visualize a behavior assignment weight is to examine
the behavior’s force vector during a crowd simulation. The vector’s length
indicates the behavior’s weight upon the delegate.
Each behavior has its own parameters which appear in the Behavior rollout,
available in the Crowd object’s Modify panel. These parameters describe how
the behavior works, and can sometimes contribute to the behavior’s strength
as well. For instance, Seek, Repel, Wall Seek, and Wall Repel, all have specific
volumes of influence. Outside these volumes they have no effect and essentially
have a weight of zero. This rollout lets you specify whether or not you wish
to see behavior’s force vector dynamically displayed during a Crowd
simulation, and what color that vector should be.
When working with the Crowd system, it is critical to play with behavior
assignment weights, as well as each behaviors’ parameters. Typically, you run
the simulation repeatedly, changing the weights and parameters to get the
desired result.
4774 | Chapter 17 character studio