8

Mapping Operator 191
assig ned per particle. If it’s lower, then multiple
particlesaregiventhesameID,orifit’shigher,
then the software increments the assigned ID
faster than 1 per particle .
For instance, if particles enter the event at intervals
of 1/60 of a second, and Per Second=30, then
each pair of par ticles will be assigned the same
ID. Or if particles enter the event at intervals of
1/15 of a second, and Per Second=30, then the ID
is incremented (or changed randomly) twice per
part icle.
Loop—When on, and the last ID has been assi gned,
the software loops back around to the first ID
and continues the cycle. When off, the software
assigns the last cycle ID to a ll subsequent particles.
AvailableonlywiththeCycleassignmentmethod.
Default=off.
For example, say you want the first eight particles
that enter t he event to use different materials, and
all subsequent particles to use a ninth material.
To do so, you would create a nine-sub-material
Multi/Sub-Object material and assign it to the
Material Dynamic operator. Choose the Cycle
assignment method, and set # Sub-Materials=9.
Set the Rate Per Sec value to the r ate at which
particles enter the event. Lastly, tu rn off Loop.
Sync B y—Choose the time frame for applying
animated parameters. Available only with the
Material ID and Cycle options.
•
Absolute T ime—Any keys set for parameters are
applied at the actual f rames for which they’re
set.
•
Particle Age—Any keys set for par ameters are
applied at the corresponding frames of each
particle’s existence.
•
Event Duration—Any keys set for parameters
are applied to each particle starting when it first
enters the event.
Rand Offset—When on, the software varies the
difference between the par ticle age and the
assigned material ID at random. The maximum
difference is determ ined by the numeric parameter.
Available only with the Material ID and Cycle
options.
Uniqueness group
The Uniqueness s etting varies the sequence of
assigned IDs with the Random option, and the
offset with the Randomize Age Offset option.
Seed—Specifies a randomization value.
New—Calculates a new seed using a randomization
formula.
Ma pping Opera tor
Particle View (page 2–121) >ClickMappinginanevent
or add a Mapping operator to the particle system and
then select it.
The Mapping operator lets you assign a constant
UVW mapping to the entire surface of the
particles. It works in conjunction with a map
specified in a material operator in the current
event. By animating the mapping coordinates, you
can vary the location on the material map from
whichtheparticlecoloristaken,thuschangingthe
particle color in a predictable way over time.
The Mapping operator was designed primarily to
be used w ith gradient maps, although you can use
it with any map you like. The procedure below
describesarecommendedmethodforusingthe
Mapping operator .
See also
Material Static Operator (page 2–183)
Material Frequency Operator (page 2–185)
Material D ynamic Operator (page 2–187)