8

Avoid B eh avior 1063
Note:
If you add the first behavior to the scene from
the
BehaviorAssignmentsandTeamsDialog(page
2–1052)
, a behavior rollout does not automatically
appear in the Crowd command panel. You must
first choose the behavior from the d rop-down list
at the b ottom of the Setup rollout.
Use the controls in this rollout to modify the
behavior. Following is a list of available behaviors:
Avoid Behavior (page 2–1063)
Orientation Behav ior (page 2–1066)
Path Follow Behavior (page 2–1068)
Repel Behav ior (page 2–1070)
Scripted B ehavior (page 2–1072)
Seek Behavior (page 2–1072)
Space Warp Behavior (page 2–1073)
Speed Vary Behavior (page 2–1074)
Surface Ar rive B ehavior (page 2–1075)
Surface Follow Behavior (page 2–1078)
Wall Repel B ehavior (page 2–1079)
Wa ll Seek Behavior (page 2–1081)
Wander Behavior (page 2–1083)
For a detailed description of sp ecific behaviors,
refer to the above topics. For an overall look at
behaviors, see
Assigning Behaviors (page 2–1011) .
Behaviors
Av o id Be havio r
Create panel > Helpers > Object Type rollout > Crowd >
Setup rollout > New button > Avoid Behavior
Select a Crowd object. > Modify panel > Setu p rollout >
New button > Avoid Behavior
The Avoid behavior lets you specify any object
or objects that delegates must keep away from.
As delegates approach designated objects during
the crowd simulation, they steer clear of them
while turning and/or braking as necessary. This
behavior uses three different methods to let
delegates avoid each other and other objects: Steer
To Av o i d , Re p e l , a n d Ve c tor Fi e ld .
Steer to Avoid behavior is best used for animals
that steer around each other at close proximity.
Earthbound animals and fish typically do this.
Steering motion may be sudden since its action is
often engaged for relatively short periods of time.
By contrast, Repel avoidance behavior mimics the
continuo us action of a repellent magnetic field.
Birds, bats and flying insects are best animated
with large Repel fields so that they can smoothly
avoid each other while maintaining a comfortable
margin of error . Repel forces prevent intrusion
from all sides, regardless of the direction of travel.
Thus even animals that rely mainly on Steer
to Avoid will also need some degree of Repel
avoidance to maintain spatial separation when
theyaremovingthroughdensetraffic.Theforces
of Repel avoidance are always directed uniformly
outward in a spherica l shape.
Use Vector Field avoidance for cases where
crowd members must avoid hitting the more
complexshapesofarbitrary3dsMaxobjects.The
outward forces of the Vector Field avoidance can
constructed to form the shape of any object. F or