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1012 Chapter 14: Character Studio
• Speed Vary B ehavior (page 2–1074) —Lets
delegates change speed for more realistic
movement.
•
Surface Ar rive Behav ior (page 2–1075) —Lets
delegates move toward and land on a surface,
w ith custom speed and acceleration parameters.
•
Surface Follow Behavior (page
2–1078)
—Delegates move a long a surface,
which c an be animated. Also, you can specify
whether the delegates are to move straight
ahead or ski rt hills and depressions.
•
Wall Repel Behavior (page 2–1079) —Uses a
grid to repel delegates; ideal for keeping objects
inside an enclosed, straight-sided room.
•
Wa llSeek Behavior (page 2–1081) —Uses a
grid to attract delegates. You can use this as a
doorway for crowd-controlled bipeds to walk
through.
•
Wander Behavior (page 2–1083) —Induces a
realistic semi-random movement for characters
such as shoppers at a mall.
Tip: If you need custom behav iors, you c an create
your own with scripting.
Thefirsttimeyouaddabehaviortothescene,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 a vailable in
the rollout for a behavior type, follow the link from
its entry in the above list.
In addition to the controls a vailable in behavior
rollouts, you can use the
Behavior Assignments
and Teams dialog (page 2–1052)
to turn behaviors
on and off (with t he 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 B eha vi ors
To use a behavior, you apply it to a delegate or a
team of delegates using the
Behavior Assignments
and Teams dialog (page 2–1052)
.Inthisdialog,
each assignment of a behavior to a delegate is given
a weight. You can modify and/or animate t hese
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
toexaminethebehavior’sforcevectorduringa
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 b ehavior works, and can
sometimes cont ribute to the behavior’s strength
aswell.Forinstance,Seek,Repel,WallSeek,and
Wa ll Repel, al l have specific volumes of influence.
Outside these volumes they have no effect and
essentially have a weight of zero. This rollout
letsyouspecifywhetherornotyouwishtosee
behav ior’s force vector dy namically displayed
during a Crowd simulation, and what color that
vector should be.
When working with the Crowd system, it is critical
to play with b ehavior assignment weights, as well
as each behaviors’ parameters. Typically, you run
the simulation repeatedly, changing the weights
and parameters to get the desired result.