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186 Chapter 11: Space Warps and Particle Systems
Inter face
The user interface appears in the parameters panel,
ontherightsideoftheParticleViewdialog.
Assign M aterial—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 Ma terial I D—When on, the operator defines
a material ID number for each part icle, and
enables the remaining p ar ameters. Default=on.
In general, this should remain on. Particle Flow
uses the m aterial ID w ith 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 the viewports.
# 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 all 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 mater ial ID 1 as it would material ID 3,
and one-tenth as likely to be assigned ID 5 as it
would ID 1.
The actua l sequence of material ID assignments
is random, and can be varied by changing the
Uniqueness Seed setting.
Uniqueness group
The Uniqueness setting varies the random
sequence of assigned ID s.
Seed—Specifies a randomization value.
New—Calculates a new seed using a randomization
formula.