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Sub-Object Clone Options Dialog 1239
Cho rd L e n g t h —
Chooses the chord-length
algorithm for reparameterization.
Chord-length reparameterization spaces knots
(in
parameter space (page 3–1082) )basedonthe
square root of the length of each curve segment.
Chord-length reparameterization is usually the
best choice.
Unifor m—Spaces the k nots uniformly.
A uniform knot vector has the advantage that
thecurveorsurfacechangesonlylocallywhen
you edit it. With chord-length p arameterization,
moving any CV can potentially change the entire
sub-object.
Mainta in Par ameterization—When on, the curve is
automatically reparameterized as you edit it, using
the c urrently active method of reparameterization.
When off, no reparameterization happens unless
you use this dialog. Default=off.
Prev iew—If on (the default), displays the effects of
reparameter izing in viewports.
Sub-Obj ect Clone Opt ions Di alog
Modify panel > Select NURBS surface or curve sub-object.
> SHIFT+Clone. > Clone Options dialog
When you SHIFT+Clone (page 1–463) asurface
or curve sub-object, the C lone Options dialog
appears. This dialog asks whether you want the
clone to be a relational copy, an independent copy,
or a transform.
Interf ace
Relational Copy—The cloned object is the same
typeastheoriginal. Iftheoriginalobjectwasa
dependent object, the clone includes copies of the
parents. F or example, when you clone a Blend
surface,thecloneremainsaBlendsurfaceandits
two parent surfaces are copied along with it.
Becauseallrelatedsub-objectsarecopied,
Relational Copy can be time-consuming.
Independent Copy—The cloned object is an
independent CV curve or CV surface. It has
the same shape as the ori ginal, but its relational
dependencies aren’t copied. This method of
cloninguseslesstimeandmemory,although
you lose the relational properties. For example,
when you clone a Blend surface, the clone is an
independent CV surface.
Copy as Transfor m Object(s)—The "clone" is
actually a transform curve or transform surface,
based on the original object and still dependent
onit.Thisletsyoucreatetransformcurvesand
surfaces based on a rotation and scale as well as
on translation.
Include Parent(s)—(Available only for Independent
Copy or Copy as Transform Object(s).) Tells the
system whether or not to include the parents of
the dependent object. For example, if Include
P arent(s) is on when you clone a blend surface, the
two parent surfaces are also cloned as independent