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1174 Chapter 9: Surface Modeling
Chord-length reparameterization is usually the
best choice.
Unifor m—Spaces the knots uniformly.
A uniform knot vector has the advantage that the
curve w ill change only locally when you edit it.
With the other two forms of parameterization,
moving any CV can change the entire cur ve.
2D V iew—When on, displa ys the Edit Curve on
Surface dialog (page 1–1229),whichletsyou
create the curve in a two-dimensional (UV)
representation of the surface.
CV Curve on Surface rollout (modification tim e)
Trim Controls group
Trim—When on, t rims the surface against the
curve. When off, the surface isn’t trimmed.
If it’s impossible to trim with this curve, the surface
is displayed in the er ror color (orange by default).
Forexample,thecurveisunusablefortrimmingif
it doesn’t form a closed loop.
Flip Trim—When on, trims the surface in the
opposite direction.
Automatic Reparam e ter ization group
The radio buttons in this group box let you
choose automatic reparameterization. With
reparameterization, the curve maintains its
parameterization as you edit it. Without
reparameterization, the curve’s parameterization
doesn’t change as you edit it, and can become
irregular.
None—Do not reparameterize.
Chord L e n g t h —Cho o ses the chord-length
algorithm for reparameterization.
Chord-length reparameterization spaces knots (in
parameter space (page 3–988)) based on the square
rootofthelengthofeachcurvesegment.
Chord-length reparameterization is usually the
best choice.
Unifor m—Spaces the knots uniformly.
A uniform knot vector has t he advantage that the
curvewillchangeonlylocallywhenyoueditit.
With the other two forms of p a rameterization,
moving any CV can change the entire c urve.
Replace Surface—Lets you replace the parent
surface. Click a button, then click a surface to
replace the original parent surface.
Edit—Click to display the Edit Cur ve on Surface
dialog (page 1–1229), which lets you edit the curve
in a two-dimensional (UV) representation of the
surface.
To edit multiple curves on a surface, select more
than one CV curve sub-object on the same surface,
then click E dit.
Rebuild—Displays the Rebuild CV Curve dialog
(page 1–1236) to let you rebuild the CV curve on
surface.
Reparam—Displays the Reparameterize dialog
(page 1–1237) to let you reparameterize the CV
curve on sur face.