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1226 Chapter 9: Surface Modeling
Reparameterization group
These controls let you reparameterize the CV
cur ve 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 curve segment.
Chord-length reparameterization is usually the
best choice.
Unifor m—Spaces the knots uniformly.
A uniform knot vector has the advantage that the
curve changes only locally when you edit it. With
chord-length parameterization, moving any CV
canpotentiallychangetheentiresub-object.
Mainta in Para meteriza tion—When on, the curve is
automatically reparameterized as you edit it, using
the currently active method of reparameterization.
When off, no reparameterization happens
unless you use a dialog to specifical ly request it.
Default=on.
Point Curve options:
These are the options when you choose Point
Curve.
Number—Sets the number of points in the point
cur ve.
Tolerance—When chosen, the software calculates
the number of points. This option rebuilds the
curve according to accuracy. The lower the
Tolerance value, the more accurate the rebuild.
Increasing Tolerance enables the curve to be
rebuilt using fewer points.
Prev iew—When on, the effect of the conversion is
previewed in viewports. Default=on.
Convert Curve on Surface Dialog
Modify panel > Select NURBS object. > Stack display >
Curve sub-object level > Selec t curve sub-object. > Curve
Common rollout > Mak e COS button
This dialog converts a curve to a point cur ve on
surface (page 1–1175) or CV curve on surface (page
1–1172). The Make COS button that displays it is
enabled only for the following types of curves:
• U iso curves (page 1–1168)
• V iso curves (page 1–1168)
• Normal projected c urves (page 1–1169)
• Vector projected curves (page 1–1171)
• Surface-surface intersection curves (page
1–1166)
• Surface edge curves (page 1–1177)
• CV curves on surfaces (page 1–1172)
• Point c ur ves on surfaces (page 1–1175)
Ifthecurveisalreadyacurveonsurface,this
dialog lets you change its type.
Interfa ce
CV Curve on S u rf ace—Converts the curve to a CV
curve on sur face.
Number of CV s —Specifies the number of CVs in
the new curve.
Point Cur ve on S urf a ce—Converts the curve to a
point c urve on surface.