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238 Chapter 11: Space Warps and Particle Systems
Usi ng M ul ti /S ub-Obj ect Ma ter ia l s
with Par ticle Systems
Particles with a Multi/Sub-Object ma terial
If the assigned material is a Multi/Sub-Object
material, particles are affected in the following
ways,dependingonthesourceofthematerial:
• Icon: In most cases, each part icle, at its birth,
is assigned a different sub-material, cycling
througheachavailablesub-material. For
example, if there are only three sub-materials,
the first particle receives sub-material #1, the
second #2, the third #3, the fourth #1, and so
on. The exceptions to this are as follows:
• MetaParticles use only the first sub-material.
• Object frag ments are born at once, so all of
them use only the first sub-material.
• Picked Emitter: When used with object
fragments as p articles, each particle uses the
three ID numbers in the Fragment Materials
group. If this source is used with the other
particle types, t he part icles are assigned
sub-materialsinthesamewayaswhenIconis
chosen.
• Inst anced Geometry: When used with
Instanced Geometry particles, each particle
is assigned a sub-material in exactly the same
way as the source object, so each particle looks
just like the source object. When used w ith
other particle types, the part icles are assigned
sub-materialsinthesamewayaswhenIconis
chosen.
Note: Instanced objects with Multi/Sub-Object
materials cannot be image motion blurred.
Usi ng S pa wned Pa rt icles
The examples in this topic start you out with a very
simple spawning using t he Super Spray part icle
system.
Exa mple: Setting up the par ticle sy stem:
1.
In the Perspective viewport, create a pyramid
that’s 5 units in all d imensions.
2. Create a cylinder with a radius and height of
3,and6 sides.
3. InthecenterofthePerspectiveviewport,create
aSuperSprayemitter.
4. Set Speed in the Par ticle Motion group (Particle
Generation rollout) to 3.0.
5. OntheParticleTyperollout,chooseInstanced
Geometry,thenintheInstancingParameters
group click Pick Object, and select the py ramid.
6. In the Viewport Display group of the Basic
Parameters rollout, choose Mesh and set the
Percentage of Particles to 100.
7. On the Particle Generation rollout, choose Use
Rate , and set the spinner to 1.
8. Set Emit Start and Emit Stop to 0,setDisplay
Until to 100,setLifeto10,andleaveVariation
at 0.
9. Under Part icle Size, set Grow For and Fade For
to 0.
10. Drag the time slider between frames 0 and 15.
A single pyramid particle emerges from the
emitter,movesup,andthendiesanddisappears
at frame 10.