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Object Space (Biped) 1077
Most modifiers (page 3–1068) operate in object
space. See
Object-Space Modifiers (page 1–537) .
Obj ect S pace (B i ped)
When you use freeform animation (page 3–1039)
to animate a biped, you can place a biped limb into
the space of another object, or into world space.
For example, if the biped’s hands are in the space
of a ball, then wherever the bal l moves the hands
move with it. If the biped’s feet are in world space,
then when you move the center of mass, the feet
stay planted in the same location.
Obstacle-Avoidance B ehavior
In crowd animation (page 2–1006) ,animportant
part of crowd behavior is avoidance of obstacles.
Think of an obstacle as anything that impedes a
crowd membe r’s progress. Examples of obstacles
include walls, telephone poles, and fences, as
well as other crowd members. Encountering
such objects can cause avoidance behavior, which
consists of any combination of slowing down,
turning, and stopping.
Obj ect-S pace Modi fier s
Object space is the coordinate system unique
to each object in your scene. An object-space
modifier, as opposed to a
world-space modifier
(page 3–1130)
, directly affects an object using the
object’s local coordinates.
Object-space modifiers appear directly above the
object in the
modifier stack (page 3–1067) ,and
their effect can depend on the order they appear
in the stack.
Omnidi rectiona l Light
Above: Top view o f an omni light
Below: Perspective view of the same light
Omnidirectional (omni) lights are standard light
objects (page 2–1142)
that provide a p oint source
of illumination that shoots out in all directions.
They’re easy to set up, but you can’t restrict the
focus of their beam. You can, however restrict
which objects are illuminated by an omni light.
When no lights exist in your scene, two invisible
omni lights are turned on by default to provide
overall illumination in t he scene. However, as soon
as you create your own light in the scene, the two
default lights are turned off.
You can apply attenuation to omni lights.