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FFD(Cyl) Space Warp 91
Only In Volume—
Only vertices that lie inside the
source volume are deformed. Vertices outside the
source volume are not affected.
All Ver tices—All vertices are deformed regardless
of whether they lie inside or outside the source
volume,dependingonthevalueintheFalloff
spinner. The deformation outside the volume is
a continuous extrapolation of the deformation
insidethevolume. Thedeformationcanbe
extreme for points far away from the source lattice.
Fa lloff—This spinner, enabled only when you
choose All Vertices, determines the distance from
the lattice that the FFD effect will decrease to zero.
When this spinner is set to 0, it’s effect ively turned
off, and there is no falloff; that is, all vertices are
affected regardless of their distance from the
lattice. The units of the Falloff parameter are
specified relative to the size of the lattice: A falloff
of 1 means that the effect will go to 0 for points that
are a lattice width/length/height away from the
lattice (depending on which side they are on).
Tension/Continuity—Lets you adjust the tension
and continuity of the deformation splines.
Although you can’t see the splines in an FFD, t he
lattice and control points represent the structure
that controls the splines. As you adjust the control
points, you alter the spli nes (which move through
each point). The splines, in turn, deform the
geometry of the object. By altering the tension and
continuity of the splines, y ou alter their effect on
the object.
Selection group
These options provide additional methods of
selecting the control points. You can toggle the
stateofanycombinationofthethreebuttonsto
select in one, two, or three dimensions at once.
AllX,AllY,AllZ—When one of these buttons is on
and you select a control point, all control points
along the local dimension specified by the button
are selected as well. By turning on two buttons,
you can select a ll cont rol points in two dimensions.
About—Displays a dialog with copyr ight and
licensing information.
FFD(Cyl) S pa ce Wa rp
Create panel > Space Warps > Geometric/Deformable >
Object Type rollout > FFD(Cyl)
Create menu > Space Warps > Geometric/D eformable >
FFD(Cyl)
Free-form deformations (FFDs) provide a method
of deforming an object by adjusting the control
points of a lattice. The offset position of the control
points to the ori ginal lattice source volume causes
the distortion of the affected object.
The FFD(Cyl) space war p uses a cylindrical array
of control points in its lattice. This FFD is available
as both an object modifier and a space warp. For
information on the object modifier version, see
FFD (Box/Cylinder) Modifiers (page 1–677) .
You create FFD space warps as separate objects
similarlytothewayyoucreatestandardprimitives:
by drag g ing the mouse in the viewport. The result
is a lattice of control points. The source lattice
of an FFD modifier is fitted to the geometry it’s
assigned to in the stack. This might be a whole
object or a sub-object selection of faces or vertices.
BecauseFFDspacewarpsareseparateobjects,they
carry their ow n adjustable dimension parameters
among the creation parameters.
You can apply object modifiers to space warp
objects. For example, you can use the Linked
XForm modifier with a space-warp FFD.