9

Position Icon Operator 147
The Uniqueness setting enables randomization of
maximumparticleageusingtheByParticleAge>
Va r i a t i o n s e t t in g .
All Particles—Deletes all particles in the event
immediately.
Selected Par ticles Only—Deletes particles selected
attheParticlesub-objectlevelintheevent
immediately. See S election rollout (page 2–138).
By Par ticle Age—Deletes particles in the event after
they’ve existed for a specific length of t i me, with an
optional random variation. Choosing this makes
theLifeSpanandVariationsettingsavailable.
Life S pan—Thenumberofframesoflifeallowed
to the particles. After this period, they’re deleted.
Default=60.
Variation—The maximum amount by w hich Life
Span may vary. To get each particle’s actual life
span, this value is multiplied by a random number
between -1.0 and 1.0, and then added to Life Span.
Default=10.
Uniqueness group
The Uniqueness setting enables randomization of
maximumparticleageusingtheByParticleAge>
Va r i a t i o n s e t t in g .
Seed—Specifies a randomization value.
New—Calculates a new seed using a randomization
formula.
Transforms
Posit ion I con Opera tor
Partic le View (page 2–125) >ClickPositioninaneventor
add a Position operator to the particle system and then
select it.
By default, particles are born, or emitted,fromthe
Particle Flow icon. This topic uses the term emitter
to refer to this icon. Use the Position Icon operator
to control the initial placement of particles on the
emitter. You can set the emitter to emit particles
from its surface, volume, edges, vertices, or center.
And, if you animate the emitter, you can cause its
motion to be imparted to the particles it emits.
Alternatively, you can use Position Object (page
2–148) to emit particles from any other object.
Interfa ce
The user interface appears in the parameters panel,
on the right side of the Particle View dialog.
Lock On E mi tte r —Whenon,causesallparticlesto
remain at their initial positions on the emitter. In