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436 Chapter 6: Transforms: Moving, Rotating, and Scaling Objec ts
1. User selects single objec t.
2. User clicks Use Transform Coordinate Center from Use Center
flyout on Main toolbar.
3. User adds second object to selection.
4. Transform center c hanges to Use Selection Center when
selectio n set contai ns m ore than one object.
5. U ser clicks Use Pivo t Point Center while multiple objects
still selected.
6. User selects single objec t.
7. Transform center returns to Use Transform Coordinate
Center (see step 2).
8. User selects multiple objects.
9. Transform center returns to Use Pivot Point Center (see step
5).
Tra nsf ormi ng About S napped Points
While the transform center choices are of ten useful
at the object level, they are not usually convenient
when transforming sub-object selections. You can
override the active transform center and perform
the current t ransform about a temporary point
by using snaps. When Snaps is active, and your
selection is locked, the p oint you snap to will set
the point about which the transform is performed.
Usingthistechnique,youcan:
• Moverelativetotwosnappoints.
• Rotate about a snapped point.
• Scale about a snapped point.
For more details, see Snap Settings (page 2–41).
Ani mati on a nd t he Tra nsfor m Center
Because of the nature of keyframing, you can
animate rotation and scale transforms properly
only by using an object’s local pivot point. For
example, while modeling, you c an rotate an object
that’s offset from the world origin around the
world center coordinate system. The object sweeps
around the origin in a large arc. However, if you
attempt to animate this, the object rotates about its
localaxisandmovesinastraightlinefromone
end of t he arc to the other.
To avoid this discrepancy, if the Auto Key button is
on and either the Rotate or Scale button is active,
the Use Center flyout is unavailable and set to Use
Pivot Point. When the Auto Key button is off,
all t ransfor ms use the center settings previously
described.
You can override this behavior by turning off
Local Center During Animate (page 3–830) in the
Animation Preferences settings.
Keep in mind that this affects only the center of
the transform. The orientation of the selected
transformcoordinatesystemisstillineffect.
Animating "Off-Center"
You can animate a rotation or scale about an
off-center point by linking your object as the child