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1228 Chapter 9: Surface Modeling
Number—
When chosen, the spinners set the
number of CVs in the CV surface.
In U—Sets the number of CV rows ( in the surface’s
U axis).
In V —Sets the number of CV columns (in the
surface’s V axis).
Tolerance—When chosen, the software calculates
thenumberofCVs. Thisoptionrebuildsthe
surface according to accuracy. The lower the
Tolerance value, the more accurate the rebuild.
Increasing Tolerance enables the surface to be
rebuilt using fewer CVs.
Reparameterization group
These controls let you reparameterize the CV
surface and turn on automatic reparameterization.
Cho rd Le n g t h —Chooses the chord-length
algorithm for reparameterization.
Chord-length reparameterization spaces knots (in
parameter space (page 3–988)) based on the square
root of the length of each segment.
Chord-length reparameterization is usually the
best choice.
Unifor m—Spaces the knots uniformly.
A uniform knot vector has the advantage that the
surface changes only locally when you edit it. With
chord-length parameterization, moving any CV
can potentially change the entire surface.
Mainta in Para meteriza tion—When on, the
surface is automat ically reparameterized
as you edit it, using the currently act ive
method of reparameter iz ation. When off, no
reparameterizationhappensunlessyouusea
dialog to specifically request it. Default=on.
Prev iew—When on, viewports display a preview of
the conversion. Turning off this toggle can speed
up conversion, especia lly to lofts.
Delete Original Cur ves—This is available only if the
surface was already a U loft or UV loft. When on,
Convert Surface deletes the original loft curves
when you click OK. When off, the original curves
remain where they are. Default=off.
CV Curve: Close Cur v e Di al og
Create panel > Shapes button > CV Curve button > In
viewports, draw a CV curve and click to create a CV in the
same location as the first CV in the c urve.
Modify panel > Selec t NURBS object. > NURBS toolbox
>CreateCVCurve>Inviewports,drawaCVcurve
sub-object and click to create a CV in the same location
as the first CV in the c u rve.
This dialog lets you create a closed CV curve w hen
you click to create a CV in the same loc ation as the
curve’s first CV.
Interfa ce
Yes—Closes the curve and ends curve creation.
No—Keeps the curve open and does not en d curve
creation.
Detach Dia log (NURB S)
Modify panel > S elec t a N URBS sub-object. > Curve
Common or Surface Common rollout > (optional) Copy
toggle > D etach button
This dialog appears when you use D etach to
create a new top-level NURBS curve or surface
sub-object.