9

190 Chapter 11: Space Warps and Particle Systems
Inter face
The user interface appears in the parameters panel,
ontherightsideoftheParticleViewdialog.
Assign Materia l—When on, the operator assigns a
material to the particles. Default=on.
[button]—Use this button to assign a material to
the operator. Click the button and then use the
Material/Map Browser to choose the material.
Alternatively, drag the material from a Material
Editor sample slot to the button. After you assign a
material to the operator, its name appears on the
button.
Assign Material ID—When on, the operator defines
a material ID number for each par t icle, and
enables the remaining par ameters. Default=on.
In general, this should remain on. Particle Flow
uses the m aterial ID with compound materials to
know which sub-material to assign to a particle.
Show In V iewport—When on, the material is shown
applied to the particles in t he v iewports.
# Sub-Materials—Displays the number of
sub-materials in the assigned material.
Material ID #1–10—Specifies the relative likelihood
of particles to be assigned the corresponding
material ID. Assign values for all IDs, or
sub-materia ls, in the material that you want to
have applied to the particles. So, for example,
w ith a Multi/Sub-Object material containing five
sub-materials, you’d set values for Material IDs
#1-5.
This value is not absolute, but relative to the other
settings. To follow the previous example, if you
wanted al l five materials to appear with equal
frequency, you’d set the same non-zero value
for Material IDs #1-5; the actual value wouldn’t
matter. On the other hand, if you wanted the
materials to appear with decreasing frequency,
you’d set the lower Material ID settings to relatively
higher values; say 100, 80, 50, 33, and 10. In this
case,eachparticlewouldtwiceaslikelytobe
assigned material ID 1 as it would material ID 3,
and one-tenth as likely to be assig ned ID 5 as it
would ID 1.
The actual sequence of m aterial ID assignments
is random, and can be v ar ied by changing the
Uniqueness Seed setting.
Uniqueness group
The Uniqueness setting varies the random
sequence of assigned IDs.
Seed—Specifies a randomization value.
New—Calculates a new seed using a randomization
formula.