9

Dynamics Utility 687
The effects of collisions b etween objects depend
on the velocity of the objects and their properties.
For collision to work between two objects, each
object must have the other object assigned for
collision. For example, when bouncing a ball, both
thefloorandtheballareassignedcollisions.
The Materi al Editor: The Dynamics Properties
rollout (page 2–1479) in the Material Editor lets
you assign the dynamics properties to the surface
of an object, like friction and bounce. Using a
multi/sub-object material, you can have different
surface properties at the face level of any object.
Note: You can override m aterial surface dynamic
properties with controls on the Edit Object dialog
(page 2–696) in the Dynamics utility.
Dy nam ics Objects, Part icles and D yna mics,
Dynamics Inter face: Special objects like Spring
and Damper, Space Warp forces like Gravity
and Wind, as well as Space Warp deflectors
like PDynaFlect can all influence a dyna mics
simulation. You must create these objects and
space warps first in other areas of 3ds Max before
you can use them in a dynamics simulation. See
the following topics for details on their creation
and u se:
•Createpanel>Geometry>Dynamics Objects
(page 1–395)
You can use the Spring and D amper objects for
dynamics effects.
•Createpanel>Space Warps (page 2–55) >
P articles and Dynamics.
Effects (forces) are special space-warp objects
that emulate natural phenomena, such as wind
or gravity. In a dynamics simulation, you must
placegravityinthesceneifyouwanttheobjects
in your simulation to fall.
•Createpanel>Space Warps (page 2–55) >
Dynamics Interface.
TheDynamicsInterfacespacewarpscancause
particles to deflect from and affect an object in
asimulation.
Combine Keyf r a med Object s i n a Simulat ion:
Keyframe an object and have it interact with other
objectsinadynamicssimulationbyturningon
theThisObjectisUnyieldingcheckboxintheEdit
Object dialog for the keyframed object. Objects
can bounce off of a keyframed sphere for example.
Dynamics Controller: WhenaDynamics
simulation is solved, a new list controller is created
thatholdsboththegenerateddynamicskeysand
the original keys. This al lows you to restore your
original keys, if necessary. Undo is not supported
by Dynamics.
For example, if a sphere is bouncing in a Dynamics
simulation,andthespherealreadycontains
position keys from a previous animation, the
following tracks display in Track View:
Transform
Position
Dynamic Position Controller
Old Position
Rotation
Dynamic Rotation Controller
Old Rotation
Procedures
Example: To create a basic simulation of bouncing
boxes:
1.
Create a thin box in the Top viewport.
Havetheboxalmostthesameheightandwidth
as the viewport. This will act as the ground
plane.
2. In the Front viewport, create six small bo xes
above the "ground" bo x.
P osition some of them to collide with each
other when they fall.