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258 Chapter 11: Space Warps and Particle Systems
to most. Thus, Emitter Rotation is more costly
than Emitter Translation, which is more costly than
Creation Time.
Par ticle Size group
Thesespinnersspecifythesizeoftheparticles.
Size—This animatable parameter specifies the
target size for all particles in the system, depending
onthetypeofparticle:
•
Standard Par ticles—The major dimension of
the particle.
•
Co nstant—The dimension, in rendered pixels,
of a Constant type of particle.
•
Object Fragments —No effect.
Variation—Thepercentagebywhichthesizeof
each particle may vary from the no rm. This is
applied to the Size value. Use this parameter to get
a realistic mix of large and smal l particles.
Grow For—Thenumberofframesoverwhichthe
part icle grows from being very small to the Size
value.TheresultissubjecttotheSize/Variation
value, since Grow For is applied after Variation.
Use this parameter to simulate natural effects such
as bubbles g rowing as they reach the sur face.
Fade For—Thenumberofframesoverwhichthe
particle will shrink to 1/10th its Size setting prior
toitsdeath.ThisisalsoappliedafterVariation.
Use this parameter to simulate natural effects such
as sparks fading to ash.
Uniqueness group
By changing the Seed value in this spinner, you
achieve different results using otherwise identical
particle settings.
New—Randomly generates a new seed value.
Seed—Sets a specific seed value.
Par ticle Type Rollout
Create pa nel > Geometry button > Choose Particle
Systems from the drop-down list. > Object Type rollout >
SuperSpray/Blizzard/Parray/PCloud > Particl e Type rollou t
Select a SuperSpray/Blizzard/Parray/PCloud emitter. >
Modify panel > Particle Type rollout
Left: A stream from a fountain
Right: The same stream with various types of particles
The controls on this rollout let you specify the
type of particle used and the type of mapping
performed on the par ticles.