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908 Chapter 14: character studio
Treat the hands the same as the feet. Set planted
keys on the hands and feet, then move the
center of mass object to bend the knees and
elbows. See Ke y Info Rollout (page 2–954) for
moreinformationonthethreesetkeybuttons.
• You can save3ds Max objects as part of the BIP
file. If you need additional legs (for a centipede)
or extra arms or wings you can use standard
bone objects with IK chains, and save all of it
w ith the BIP file.
• The Balance Factor in the Key Info rollout Body
group, is designed to synchronize upper body
and lower bo dy movement. Set Balance Factor
to 0 if you find the movement of spine links
isaffectingthebiped’shipmovementsinan
undesirable way.
Animating I K Attachments
A biped can interact with other objects in the
3ds Max scene. Links between objects are usually
static, unless you’re using the Link controller.
In character studio, such attachments are
"animatable" as well; during the course of an
animation, the links between the hands, feet, and
objects in the scene c an change as your character
interacts with them.
This capability is useful for:
• Creating freeform motions (without footsteps
and gravit y ) that require that feet or hands b e
planted with IK, and then released. Examples
are climbing a ladder, riding a bike, or rowing
aboat.
• Motions that involve the temporary
manipulation of objects, such as bouncing or
kicking a ball, opening a door, or touching
another biped.
An object to which a hand or foot can be attached
is called an IK object. See the tutorial “Interacting
with Objects” for lessons that show you how to
make a biped iron clothing, ride a skateboard,
bounce a b asketball, climb a ladder, and pick up
abriefcase.
Procedures
To ma k e a ha nd or foot fol low a n object:
1.
Create the object for the hand or foot to follow.
2. Select the biped’s hand or foot.
Tip: You can select any part of the biped’s arm
to set keys for the hand, or any part of the leg
to set keys for the foot.
3. In the Key Info rollout (page 2–954),expandthe
IK divider to see the IK section of the rollout.
4. Click Set Key.
Once a key is set, the IK Blend value and other
IK parameters b ecome available.
5. Click Select IK Object, and choose the
object for the hand or foot to follow.
The object name appears in the field below the
Body and Object radio buttons.
6. On frames where you want the hand or
foot to start following the object, set a key, set
IK Blend to 1.0 and choose t he Object option
on the Key Info rollout. You can also click Set
Sliding K ey to set these parameters all at once.
Note: If Object space is turned on with no IK
object specified, the IK constraints will be in
Worldspace.Ineffect,thehandorfootwillbe
attached to the world, and will not move during
the time such a key is set.
Set one key when you want the attachment to
begin, and a second key when you want the
attachment to stop. This defines an Object
space interval, the duration of a temporary
attachment.
7. On the f rame that defines the end of an
attachment interval, set IK Blend to 1.0,choose