9

122 Chapter 11: Space Warps and Particle Systems
global and local (per-event) basis g ives you much
greater control over how space warps affect the
particles than with previous systems.
How do I make particles follow a path?
Yo u c a n u s e t h e Speed By Icon operator (page
2–162) or the Find Target test (page 2–218),
assigning the icon or target to a spline path. You’ll
find il lustrative procedures in both topics.
Can I use Snapshot or dynamics with Particle
Flow?
No. The Snapshot tool is not currently compatible
with Particle Flow, nor is reactor or the legacy
dynamics system.
How do I use motion blur with Particle Flow?
Youcanapplymotionbluronaper-eventbasisby
editing t he event’s object properties (page 1–117)
w ith the r ight-click menu in Particle View, or on
a global basis by editing the global event’s object
properties. In the Particle View dialog , highlight
the event to edit and then ri g ht-click and choose
Properties. On the Object Properties dialog, edit
the Motion Blur group settings.
Alternatively, you can apply motion blur to an
entire Particle Flow system without the need to
set properties by using the multi-pass motion blur
effect (page 2–1386) with a camera.
Note: Yo u c a n a l s o u s e O b j e c t P r o p e r t i e s t o s e t
other properties for events and the particle system,
as with any object in 3ds Max. Do this only within
Particle View, not using the source icon in the
view por ts (r ight-click menu > Properties or Edit
menu > Object Properties).
Note: When using Object Motion Blur, if an event
contains a Material D ynamic operator that uses
a material with a Particle Age, Part icle MBlur, or
Bitmap map, the event should not also contain a
Deleteoperator,oraSpawnorCollisionSpawn
test. Also, the event should not contain any
tests that are wired to another event. The only
exceptiontothisistheAgeTestoperatorwhen
settoAbsoluteTimewithoutanyvariation;that
is, all particles leave the event at the same time.
This applies to the use of Object Motion Blur only;
there are no restrictions with Image Motion Blur.
How do I use the Particle Age a nd Part icle M Blur
maps with Particle Flow?
To u s e t h e Pa r t icle A ge m ap w ith Pa r t i c l e F low, you
must use the Delete operator to give the particles a
finite life span. For further information, see Delete
Operator (page 2–146).
Also note the following:
• Particle Age, Particle MBlur and a Bitmap map
containing an animated bitmap can be used
only with Material Dynamic operator (page
2–191), with Same As Particle ID turned on.
You’ll find procedures for u sing Bitmap and
Particle Age at this topic.
• The particle material cannot be a submaterial;
it must be the main material.
• In the non-event-driven particle systems in
3ds Max, Par ticle MBlur is used w ith a control
named Direction Of Travel\MBlur and an
accompanying Stretch parameter. In Particle
Flow, you can replicate the stretching effect by
using a Sca le operator, turning off Sca le Factor
> Constrain Properties, and scaling the particle
along one axis.
I’m trying to apply Particle Flow to an anim ation
created with a dynamics system. Why am I
getting strange results such as unexpec ted
spawning of particles?
The dynamics system probably generates rotation
keys using the E uler XYZ controller. To avoid
interpolation discontinuities, change the rotation
controller for such objects to TCB Rotation.