8

676 Chapter 8: Modifiers
FFD Parameters rollout
Display group
Affects the display of the FFD in the viewports.
Lattice—Draws lines connecting the control points
to make a grid.
Although the viewports can sometimes become
cluttered when these lines are drawn, it helps to
visualize the lattice.
Sour ce Volume—Displays the control points and
lattice in their unmodified state.
When you’re in the Lattice selection level, this
helps to position the source volume.
Tip: Toseewhichpointslieinthesourcevolume
(andthereforewillbedeformed),temporarily
deactivate the modifier by clicking to tur n off the
light bulb icon in the mo difier st ack display.
Deform group
Only in Volume—Deforms vertices that lie inside
thesourcevolume.Default=on.
All Ver tices—Deforms all vertices, regardless of
whether they lie inside or outside the source
volume.
The deformation outside the volume is a
continuous extrapolation of the deformation
insidethevolume. Thedeformationcanbe
extreme for points far away f rom the source lattice.
Control Points group
Reset—Returns all control points to their orig inal
positions.
Animate A ll—Assigns Point3 controllers to all
control points so that they’re immediately visible
in Track View.
By default the control points of an FFD lattice
don’t appear in Track View because t hey don’t have
controllers assigned to them. But when a control
pointisanimated,acontrollerisassignedtoitand
becomes visible in Track View. With Animate All,
you can add and delete keys and per form other
key operations.
Co nform to Shape—Moves each FFD control point
to the intersection of the modified object with a
straight l ine extending between the object’s center
to the control point’s original location, plus an
offset distance specified by the Offset spinner.
Note: Conform to Shape works best with regular
shapes, such as primitives. It’s less effective if
the object has degenerate (long, narrow) faces or
sharp corners. All the controls are unavailable with
shapes, b ecause there are no faces to intersect with.
Inside Points—Only control points inside the object
are affected by Conform to Shape.