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252 Chapter 11: Space Warps and Particle Systems
Particle Generation rollout > Par ticle Motio n
group
Speed—Thespeedoftheparticleatbirthalongthe
normal, in units per fra me.
Note: For the correct volume effect, Speed should
be set to 0.
Variation—Applies a percentage of variation to the
speed of emission for each p art icle.
R andom Direction—One of three options that affect
the direction of the par ticles. This option emits
particles in random directions.
Direction Vector—Specifies the direction of the
particlesbyavectordefinedbythethreeX,Y,and
Zspinners.
X/Y /Z—Displaystheparticledirectionvectors.
Reference Object—Emits particles in the direction
of the loca l Z axis of a specified object.
Object—Displaysthenameofthepickedobject.
Pick Object—Clickthis,andthenselectanobjectin
the scene to u se as a reference object. This button is
availableonlywhenyouchooseReferenceObject.
Variation—Applies a percentage of variation to the
directionwhenyouchooseeithertheDirection
Vector or Reference Object option. This spinner
is unavailable and has no effect when you choose
Random Direction.
PArray Particle System
Create pa nel > Geometry button > Choose Particle
Systems from the drop-down list. > O bject Type rollout
>PArray
Create menu > Particles > PArray
Basket used as a d istr ibution object for random par ticles
over its surface
The PAr ray (Par ticle Array) particle system
provides two types of particle effects:
• You can use it to emit particles using a selected
geometric object as the emitter template (or
pattern) for the emission. This object is referred
to here as the distribution object.