8

Position Icon Operator 143
The Uniqueness sett ing enables randomization of
maximumparticleageusingtheByParticleAge>
Va r i at i o n s e t t i n g .
All Particles—Deletes all particles in the event
immediately.
Selected Par ticles Only—Deletes particles selected
attheParticlesub-objectlevelintheevent
immediately. See
Selection rollout (page 2–134) .
By Par ticle Age—Deletes particles in the event after
they’ve existed for a specific length of time, with an
optional random variation. Choosing this makes
theLifeSpanandVariationsettingsavailable.
Life Span—Thenumberofframesoflifeallowed
to the part icles. 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 sett ing enables randomization of
maximumparticleageusingtheByParticleAge>
Va r i at i o n s e t t i n g .
Seed—Specifies a randomization value.
New—Calculates a new seed using a r andomization
formula.
Transfo rms
Posit ion Icon Oper ator
Particle View (page 2–121) > Click Position in an event or
add a Position operator to the par ticle s ystem and then
select it.
By default, particles are born, or emitted ,fromthe
Part icle 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 c ause its
motion to be imparted to the particles it emits.
Alternatively, you can use
Position Object (page
2–144)
to emit particles from any other object.
Interfa ce
The user interface appears in the parameters panel,
on the right side of the P article View dialog.
Lock On E mi tt er —Whenon,causesallparticlesto
remain at their initial positions on the emitter. In