8

568 Chapter 8: Modifiers
ThedefaultvalueissettobethesameasEarth’s
gravit y: -980.0 cm /sec
2
.
Step—Themaximumsizeofthetimestepthe
simulator takes.
This value is measured in seconds. The value
must be less than the leng th of one frame (less
than 0.033333 for 30 fps animation). A va lue of
0.02 is generally the largest value you want to
use. Reducing this value causes the simulator to
take longer to calculate, but will in general give
better results. The simulator w ill automatically
reduce its time steps as needed, but this is the
maximum value that it will try. This value works
in conjunction with the Subsample parameter:
The actual maximum value=Step value div ided
by Subsampl value.
Subsa mple—Thenumberoftimesperframethat
the software samples the posit ion of s olid objects.
Default=1.
At the default value, Cloth samples the solid objects
in the simulation once every frame. Increasing
this value should help when objects are moving or
rotating quickly, but b e aware that the higher you
set the value, the slower the simulation will be.
Start Frame—The frame at which the simulation
starts. If you change this value after the simulation
has b een performed, the cache w ill be move d to
this frame. Default=0.
End Frame—When on, determines the f rame at
which the simulation will stop. D efault=100.
Self Collision—When on, detects cloth-to-cloth
collisions. Leaving this off will speed up
the simulator, but will allow cloth objects to
interpenetrate.
The numeric setting specifies the extent to which
Cloth tends to avoid self-colliding cloth objects,
at the cost of simulation t ime. Range=0 to 10.
Default=1.
This is a maximum limit. If C loth needs fewer
calculat ions to resolve all collisions, it will use
fewer. In most cases, a va lue greater than 1 isn’t
necessar y.
Solid Collision—When on, the simulator takes into
account cloth-to-solid o bject collisions. This is
almost always left on.
Use S ewing S prings—When on, uses the sewing
springs created w ith Garment Maker to pull the
fabric together.
This works only with objects that have been
made with
Garment Maker (page 1–587) .Turn
this option off once the garment has been pulled
together. When off, C loth will identify vertices
that are sewn together and will always keep them
coincident.Whenon,thereisalwaysachancefor
theverticestocomeapartifthesewingspringsare
not strong enough (actually, there will always be
some slight gap between the vertices in this case).
Show Sewing Spr ings—Tog g l e s th e v i s u a l
representation of the sewing springs in the
vie wports. These do not render.
Sim on R ender—When on, triggers t he simulation
at render time. Use this for generating a simulat ion
w ith a network computer, which lets you continue
to work on other aspects of your scene with your
own computer. See a procedure
here (page 1–561) .
After the render is completed, Cloth writes a cache
for each cloth object. You can specify this cache file
on the
Selected Object rollout (page 1–565) (which
is available only when a single object is selected).
If you do not specify a name, the software creates
one.
Thenumericvalueindicatesthepriorityofthe
simulation; the simulations are run in ascending
order. For modifiers with the same priority, the
order is undefined.
Note: Each object has its ow n cache file, w hich is
temp orar i ly created when the MA X fi le is opened.