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182 Chapter 11: Space Warps and Particle Systems
Multi-Shape R andom Order—
When on, assig ns
shapestoparticlesinrandomorder. Whenoff,
Particle Flow emits each shape in the multi-shape
object as a single particle, in the order of the
shape’s X coordinate. In other words, the shape
w ith the lowest X -axis coordinate is emitted first,
then the one with the next highest, and so on. The
optionisavailableonlyifatleastoneofSeparate
Particles For group check box es is on. Defa ult=off.
For example, if you want the particles to spell out
awordorphrase,useextrudedtextcreatedinthe
Front viewport as the reference object, turn on
Separate Particles For > Group Elements, but leave
Multi-Shape Random Order off.
Animated Shape—When on, particles use any
animationinthereferenceobject,includingcyclic
animation applied with the Parameter Curve
Out-of-Range Types controls. When off, the
particles are not animated.
With this option, you can use the A nimation Offset
K eying controls to specify how to synchronize the
reference-object animation with the particles. See
the next sec tion.
Note: Aparticlethatusesthisoptionisanimated
only while in the event containing the Shape
Instance operator. If it m oves to another event that
doesn’t contain a shape operator, it keeps the same
shape, but the animation stops. The easiest way to
keep the animation going from event to event is
toplacetheShapeInstanceoperatorintheglobal
event (page 3–949). Other wise, you need to place
theoperatorineacheventinwhichtheparticle
should be animated.
Acquire Current S hape—When on, Particle Flow
acquirestheparticleshapefromthereference
object as each particle enters the event. Thus, if the
reference object is animated, particles that enter at
different times get different shapes. However, these
shapes are not animated. When the option is off,
the shape is acquired from frame 0. Default=off.
This option is available only when Animated
Shape is off.
Animation Offset Keying group
These controls are available only when Animated
Shape is on.
Sync B y —Lets you choose how to synchronize
reference-object animation with the pa rticles.
•
Absolute T ime—All particles have the same
shape at any given moment.
•
Par ticle Age—Animation of the reference object
is synchronized with particle age: Frame 0 of
the refer ence-object animation corresponds to
the frame of each particle’s birth.
•
Event Durat ion—Frame 0 of the reference-object
animation corresponds to the moment the
part icle enters the event.
Rand Offset—When on, randomly var ies the start
of each particle’s animation. U se the numeric
setting to spe cify the number of frames by w h ich
the animation start can vary.
Update Par ticle Shape—Refreshes instanced
particle shapes from the reference object. Use this
after changing an object in a hierarc hical reference
object.
In most cases, Particle Flow automatically updates
instanced particles when changes are made to the
reference object. However, in some cases, when
youchangeanobjectdeepinahierarchy,the
particle instances might not b e updated. In such
a case, click Update Par ticle Shape to refresh the
instances.
Uniqueness group
The Uniqueness setting enables changing the
randomization of the scale variation, animation
offset, and the multi-shape random order.
Seed—Specifies a randomization value.