8

Material Static Operator 183
Related to this is the Mapping operator (page
2–191)
,whichletsyougivethesamemapping
coordinates to the entire surface of each particle in
an event, thus using a single pixel from a material
to color the particles. By animating the mapping
coordinates, you can cause the p a rticles to change
color over time. This is particularly effective with
a gradient material.
The
Bitmap map (page 2–1441) ,usedin
conjunction with Ma terial Dynamic, lets you
assign different frames from an image sequence to
particles based on the p article age, among other
effects.
Followingaresomeitemstokeepinmindwhen
using materials with Particle Flow:
•Amaterialisastaticpropertyofanevent.It
does not t ravel along with the particles from
oneeventtothenext.Aparticle’smaterialID
does,butitsmaterialdoesnot. Ifyouwant
particlesalwaystousethesamematerial,define
the material in the
global event (page 3–1043)
with a Material operator or a Shape Instance
operator (page 2–174)
. O therwise, you need to
define it in each local event.
• The primitive particle shapes available with
the
Shape operator (page 2–172) do not have
mapping coordinates. The
Mapping operator
(page 2–191)
applies the same mapping
coordinates to each particle’s entire surface, so
it’s not suitable in this situation. If you want to
apply image-based materials to part icles, use
Shape Instance (p age 2–174) instead.
•IfyouuseaMaterialoperatorwith
Shape
Instance (p age 2–174)
,besuretoapply
mapping coordinates to the
reference object(s)
(page 3–1096)
.Youcandothisbymaking
sure the object’s Generate Mapping Coords
option is on (if available), or applying a
UVW
Map modifier (page 1–905)
or Unwrap UVW
modifier (page 1–867)
.Ifyoudon’tapply
mapping coordinates, the system generates a
Missing Map Co ordinates warning when you
render the scene.
• If you use an object with a material already
applied as a
reference object (page 3–1096) for
instanced particles, you don’t need a Material
operatorinthesameevent. However,the
material appears only in the event containing
the
Shape Instance operator (page 2–174) ;it
does not persist from event to event.
•Ifyouusethe
Cache operator (page 2–193)
with Update set to Always, toggling the Material
Editor > Show Map In Viewport switch causes
P article Flow to recalculate the cache.
• You can drag a material from the Material
Editor to a P article Flow source icon, but the
materialwillnothaveanyeffectonthesystem.
YoumustuseaMaterialoperatororShape
Instance to apply materials to particles in
Particle Flow .
• Once you’ve assigned a material to a Material
operator , the material shows up in the Material
Editor as “hot”; that is, t riangles appear in the
corners of its sample slot. However, because of
the nature of the Par ticle Flow data st ructure,
the Material Editor functions Select By Material
and Get Material > Browse From Selected do
not work correctly with Particle Flow systems.
You can, however, use Get Material > Browse
From Scene.
Mater ial Static Operator
Particle View (pag e 2–121) > Click Mater ial Static in an
event or add a Material Static operator to the particle
system and then select it.
The Material Static operator lets you g ive particles
material IDs that remain constant throughout the
event. It als o lets you assig n a material to each
part icle based on its material ID. The operator
can assign the same material ID to all particles, or
different IDs to successive particles on a cyclical