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268 Chapter 11: Space Warps and Particle Systems
specific submaterial, you can assign it by changing
the Outside ID number.
Edge ID—Specifies which submaterial ID number
is assigned to the edges of the fragments.
Backside ID—Specifies which submaterial ID
number is assigned to the b ack sides of the
fragments.
R ota tion a nd Coll isi on R ollou t
Create panel > Geometry button > Choose Particle
Systems from the drop-down list. > Object Type rollout
> Su perSpray/Blizzard/Parray/PCloud > R otation and
Collision rollout
Select a SuperSpray/Blizzard/Parray/PCloud emitter. >
Modify panel > Rotation and Collision rollout
Particlesoftenmoveathighratesofspeed.Insuch
cases, you m ight want to add motion blur to the
particles to enhance their motion. Also, real-world
particles typically rotate as they move, and collide
with each other.
The options on this rollout affect the rotation of
the par ticles, provide motion blur effects, and
control inter-particle collisions.
Interfa ce
Spin Speed Controls group
Spin Time—The number of frames for one rotation
of a particle. If set to 0, no rotation ta kes place.
Variation—The percent of variation of the Spin
Time.
Phase—Sets the initial par ticle rotation, in degrees.
This has no meaning for f ragments, which always
begin with zero rotation.
Variation—The percent of variation of the Phase.