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676 Chapter 12: Animation
Static Friction—
Specifies how hard it is to start
moving on a surface. Available only if Override
Ma terial Static Friction is on.
Override Material Static Friction—Enables the Static
Friction spinner when you want to use a specific
value that’s different than that assigned by the
object’s material. When using a multi/sub-object
material, you can assign different Static Friction
values to the sub-materials, and thus to different
facesofanobject.Butifyouuseanoverridevalue,
it affects the whole object only.
Co py to Object’s Material—Copies the value in the
Static Friction spinner to the material assigned to
the object.
Sliding Friction—Sliding friction determines
how hard it’s for an object to keep moving over
a surface. Available only if Override Material
Bounce is on.
Override Material Sliding Friction—Enables the
Sliding Friction spinner when you want to
use a specific value that’s different than that
assigned by the object’s material. When using a
multi/sub-object material, you can assign different
Sliding Friction values to the sub-materials, and
thus to different faces of an object. But if you use
an override va lue, it affects the whole object only.
Co py to Object’s Material—Copies the value in the
Sliding Friction spinner to the material assigned
to the object.
Physical Properties group
Provides controls that specify the physical
properties of the current object.
Density —Specifies the density of t he object in
grams per cc. A setting of 1 is the equivalent of
water, and u sef ul for any t hing wooden, plastic, or
organic. The more dense an object, the slower it
will react to forces. There is a direct relationship
between density and mass, so w hen you alter the
Density setting, the Mass value changes (when its
automatic value is not overridden).
Mass—Technic a l l y, m ass i s t h e m e a s u r e o f h ow
many subatomic particles are in an object. In
3dsMax,it’scalculatedasaresultofdensity
times volume. Mass can is the resistance to
acceleration given a constant for c e. The greater
themass,themoreresistance. TheMassvalue,
when not overridden, is derived from the density
and volume, and the volume, when automatically
calculated, is affected by the Calculate Propert ies
Using option.
Overr ide Automatic Mass—Enables the Mass
spinner so you can specify the object’s mass.
When you override the automatic value, the Mass
valueisnolongeraffectedbytheDensityor
Volume values.
Mass is affected by the Calculate Properties Using
options.
Volume—Thevolumeoftheobject,measuredin
cubic centimeters. When automatically calculated,
this value depends on the option chosen u nder
Calculate Properties Using.
Over r ide Au tomati c Vol ume—Enables the Volume
spinner s o you can specify the object’s volume.
WhenyouoverridetheautomaticVolumevalue,
it’s no longer affected by the Calculate Properties
Using options, and it no longer affects the Mass
value.
Calculate Properties Using options
Specifies the type of geometry the simulation will
usetocalculatethemass,thevolume,andthe
mass moment. When the Mass and Volume values
are automatically calculated (their overrides are
turned off), changing these options affects the
volume, and thus the mass.
Vertices—Treats an object as a "point cloud," or
a collection of vertices without segments. Each