8

Find Target Test 219
Follow Target Animation—
Tur n on to allow
particles to follow a moving target; that is, a target
whose location is animated. This requires more
computation, because the destination must be
updated at every integration step.
Point—Lets you specify where on its target a
particle should land.
•
Random—Each par ticle targets a random point
on the target.
•
Clo se s t Surfa ce—Each particle targets the
nearest point of the target’s surface.
•
By Script Vector—The target point or points are
definedusingaScriptoperatorthatdefines
values in the part icleVector channel. The Script
operator can be anywhere upstream of the Find
Target tes t .
Note: When using By Script Vector to target
absolute posit ions, such as vertex locations,
be sure to set Target to Icon. If you set it to
Mesh, the positions specified by the script will
be relative to the position of the mesh object.
This latter option is useful for p lacing scripted
targets on the surface of a mov ing object.
Object—With multiple mesh targets, lets you
specifyhowthesoftwareshouldchooseamong
them. Available only when targeting more than
one object.
•
Random—For each par ticle, the software
choosesatargetobjectatrandom.
•
Clo se s t Pi vo t—For each part icle, the software
chooses as its target the object whose pivot is
nearest to the particle.
•
Clo se s t S u rfa ce—For each part icle, the software
chooses as its target the object whose surface is
nearest to the particle.
•
Lea st D ev i a ti on—For each par ticle, the software
chooses as its target the object that requires
the least change in its current direction (or
resteering) to reach.
•
By Script Integer—For each particle, the
choice of a targeted object is defined by a
script operator that sets an index. This index
corresponds to a target-object entry position
in the target list. See
Script Operator Example
(page 2–220)
.
Lock On Target Object—When on, the software
calculates each particle’s target object once: when
the particle enters the event. Thereafter, the
particle is “locked on” to its target object. When
off, the software can continually recalculate the
target object for each particle. Available only when
multiple target objects are designated.
For example, if you set par ticles to target the closest
surface, due to the target animation and particle
movement, the definition of the closest surface is
constantly changing. Thus the particle may change
thetargetobjectduetothecircumstances.
Note: Each time Find Target sets a target object,
it “locks on” to a sp ecific point on that object.
This point can change only if the t arget object
changes. Thus, with a single target object, the
target point always remains constant
relative to
the target object
.Thatis,ifthetargetobjectorits
surface is animated, and Follow Target Animation
orAnimatedShapeison,theabsolutecoordinates
of the target point may change.
Note: When Lock On Target Object is off, more
calculation is required because the system might
have to recalculate each part icle’s optimal target
point in e ach frame.
Dock ing Direc tio n group
Docki ng ty pe—Lets you specify from which
direction particles should approach targets.
•
None Specified—No docking constraints.
Part icles reach their targets in the most efficient
way, based on their assigned parameters and
their current attributes.