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Controlling R otation 299
Controlling R otation
Below the Transform controller is the Rotation
controller. Rotation is a data type that can use
most of the standard controllers such as TCB,
Linear, and Noise.
Rotations in 3D are very complex. Even the
standard controller types behave differently when
used for rotation. The most common way of
calculating rotations in 3D animation uses four
components to define rotation about an arbitrary
axis.Thisisthequaternion method.
The benefits of using quaternion rotation include:
• It produces a direct one-to-one relationship
between the quaternion values and how objects
interactively rotate in the scene.
• Itproducessmootherrotationthanother
methods.
The drawbacks of using quaternion rotation
include:
• Rotationvaluesinkeyinformationcanbe
difficult to understand.
• Quaternion rotation controllers do not display
function curves in Track View — Curve Editor.
For this reason Euler XYZ is now the default
rotation controller assi g ned to all objects.
You can use the following controllers only as
rotation controllers.
Smooth R otation
Use Smooth Rotation (page 2–374) when you
want rotation to have a smooth and natural
look. Smooth rota tion uses nonadjustable
curved interpolation, and has the following
characteristics:
• You can move keys in Track View to change
timing.
• You can directly rotate objects in the viewpor ts
to change rotation values.
• You cannot display controller or key properties,
or function curves.
Euler X YZ R otation
Use the Euler XYZ Rotation controller (page 2–318)
when you want individual function curve control
for each axis of rotation. Euler XYZ is a compound
controller that combines separate, single-value
float controllers to specify an angle of rotation
about each of the X, Y, and Z axes. Euler XYZ
Rotation is the default controller applied to all
objects.
Euler XYZ is not as smooth as quaternion rotation,
butitistheonlyrotationtypethatyoucanuseto
edit rotation function curves.
Euler angles are well suited for animating
mechanical rotations. They can a lso be a good
choice for an object in an inverse kinematics chain
becauseIKRotationaljointsaredefinedasEuler
angles. X, Y, and Z function curves displayed by
this controller in Track View represent rotations
in "world" or "parent" space which is the rotat ion
system used by most 3D animation p ackages.
Customers upgrading from earlier versions of the
program mi ght find some difficult y in adapting
to using Euler XYZ rotation controllers. If you
find yourself experiencing unexpec ted rotation
behavior, this might be the reason. Reassign TCB
rotation as the default rotation controller and you
will be able to regain your customary workflow.
Controlling Colors
You can animate colors in 3ds Max just like most
other p ar ameters. There are two data types used
for controlling colors.