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210 Chapter 11: Space Warps and Particle Systems
Add—
Click this button, and then select a Deflector
spacewarpinthescenetoaddittothelist.
By List—Click this button, and then use the Select
Deflectors dialog to add one or more space warps
to the list. The space warps must already exist in
the scene.
Remove—Highlight a deflector in the list, and then
click this button to remove it from the list. Any
removed space warps remain in the scene.
Test True If Particle group
Choose the condition under which the test
will pass particles on to the next event, and
then adjust the associated setting or settings.
Default=Collides.
Collides—Choose this option, and then set Speed
according to how part icle speed should be affected
by the collision.
Speed—Choose one of t he following.
Default=Bounce.
•
Bounce—The speed and direction after collision
is determined by the deflector proper ties.
•
Co ntinue—Particle speed and direction are
unaffected by the collision.
•
Stop—Particle speed is set to 0 after the
collision.
•
Random—Particlesbounceoffthedeflectorin
random directions.
Is Slow Af ter Collision(s)—The test succeeds if, after
collision, particle speed is less than the Speed Min
value.
With this choice, particle behavior with respect
tothedeflector(s)isthesameaswiththeCollides
>Bounceoption.
Speed Mi n—Particles traveling at less than this
speed, in system units per second, test Tr ue and
become eligible for moving to the next event.
Default=1.0.
Is Fast Af ter Collision(s)—The test succeeds if, after
collision, particle speed is g reater than the Speed
Max value.
With this choice, particle b ehavior with respec t
tothedeflector(s)isthesameaswiththeCollides
>Bounceoption.
Speed Ma x —Particles traveling faster than this
speed, in system units per second, test Tr ue and
become elig ible for moving to the next event.
Default=1000.0.
Collided Multiple T imes—The test becomes True
after a particle collides a specific number of t imes.
Theparticleismovedtothepointofthelast
collision and then redirected to the next event.
#Times—Thenumberoftimesaparticlemust
collide in order to test True.
Speed—Determines speed and direction after
the specified number of collisions. S ee above for
explanations of the choices.
Will Collide—The software extrapolates particle
motion in a linear fashion, based on the current
direction and speed, and the test becomes True
if the results suggest that the particle will collide
with the deflector during a specified time interval.
Theparticleisredirectedtothenexteventwithout
updating its speed or position.
#Frames—The number of frames ahead during
which the software looks for an impending
collision.
Uniqueness group
The Uniqueness setting enables r andomization of
the Random options in the Speed drop-dow n lists.
Seed—Specifies a randomization value.
New—Calculates a new seed using a randomization
formula.