8

16 Chapter 10: Precision and Drawing Aids
dummyisoftenusedthiswaytoanimatelinked
motion.
Another common usage of a dummy object is in
the animation of target cameras. You can create a
dummyandpositionatargetcamerawithinthe
dummy object. Then you can link both the camera
and its target to the dummy, and animate the
dummy with a path constraint. The target camera
will follow the dummy along the path.
Dummy objects are always created as cubes. You
can change the proportions of dummies by using
non-uniform sc aling, but avoid this on dummies
that are within a hierarchical linkage; this can
introduce unexpected results.
Procedure
To create a dummy object:
• Click Dummy and drag a cube to any
convenient size.
Inter face
Dummy objects don’t have any parameter rollouts
or settings.
Expose Tra nsform Helper
Create menu > Help er s > Stan d ard > Ex poseTm
The Exp ose Transform helper exposes values of
non-keyed objects for use in expressions and
scripts. This lets r iggers and animators access a
select set of transforms for an object, and between
an object and its parent, such as a bone in an IK
chain.Forexample,usingtheExposeTransform
helper, you could write a script or use parameter
wiring that tests the angle of an character’s
arm bone that’s controlled by IK (thus, has no
keys), and once it exceeds a specific value, rotate
the corresponding clavicle bone to deform the
shoulder area.
In the viewpor ts, the Expose Transform helper
object looks just like a
Point helper (page 2–22) .
Procedure
To use the Transform helper:
1.
Click ExposeTm and choose the appearance
characteristics from the Display rollout.
2. Adjustthesizeofthehelperobjectbyusing
theSizespinnerontheDisplayrollout.
Default=20.0
3. Click anywhere in your scene to add the helper
object.
The helper object’s position has no bearing on
its functionality.
4. On the Mo dify panel > Parameters rollout,
click the Expose Node button (default label:
None) and select the object whose t r ansform
values you want to expose.
Theobject’snameappearsonthebutton,and
its transform values appear in the fields on the
Expose Values rollout.
5. Optionally, tur n off Parent and choose a L o c al
Reference Node object.
This option is used by the Loca l Euler Angles,
Distance To Reference, and Angle parameters.
If the object has no parent and you don’t specify
aLocalReferenceNodeobject,thesefieldsuse
theworldcenter(0,0,0)asthereferencenode.
6. To use a transform value in a script or
expression, first click the M button next to the
parameter value.
This copies the transform name, using
MAXScript notation, to the copy buffer.
7. Paste the contents of the buffer to your script
or expression.
Asampleresultofthisis
“$ExposeTransform01.localPositionX”.
3ds Max interprets this as the local posit ion, on
the X axis, of t he Expose Node object.