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264 Chapter 5: Creating Geometry
Lengt h—Specifies the size of the cross–section
along the local
Y
axis.
Width—Specifies the size of the cross–sect ion
along the local
X
axis.
Angle—Adjusts the rotational position of the
cross-section in the viewport or renderer. For
example, if you have a square cross-section you
canuseAngletopositiona"flat"sidedown.
Aspect—Sets the aspect ratio for rectangular
cross-sections. The Lock check box lets you lock
the a sp ect ratio. When L ock is tu rned on, Width is
locked to Length that results in a constant ratio of
Width to Length.
Auto S mooth—If Auto Smooth is tu rned on,
the spline is auto-smoothed u s ing the threshold
specified by the Threshold setting below it. Auto
Smooth sets the s moothing based on the ang le
between spline segments. Any two adjacent
segmentsareputinthesamesmoothinggroupif
the angle between them is less than the threshold
angle.
Note: Turning Auto Smo oth on for ever y situation
doesnotalwaysgiveyouthebestsmoothing
quality. Altering the Threshold angle may be
necessary or turning Auto Smooth off may
produce the best results.
Threshold—Specifies the threshold angle in
degrees. Any two adjacent spline seg ments are put
inthesamesmoothinggroupiftheanglebetween
them is less than the threshold angle.
Interpolation rollout
These settings control how a spline is generated.
All spline curves are div ided into small straight
linesthatapproximatethetruecurve.Thenumber
of divisions between each vertex on the spline are
called steps. The more steps used, the smoother
the curve appears.
Steps—Spline steps can be either adaptive (that
is,setautomaticallybyturningonAdaptive)or
specified manually.
When Adaptive is off, use the Steps field/spinner
to set the number of divisions between each vertex.
Splines with tight curves require many steps to
look smooth while gentle curves require fewer
steps. Range=0 to 100.
Optimi ze—When on, removes unneeded steps
from straight seg m ents in the spline. Optimize is
not available when Adaptive is on. Default=on.
Adaptive—When off, enables manual interpolation
control using Optimize and Steps. Default=off.
When on, Adaptive sets the number of steps for
each spline to produce a smooth curve. Straight
segments always receive 0 steps.
Optimized spline left and adaptive spline right. Resulting
wireframe view of each, respectively, on the right.
The main use for manual interpolation of splines is
in morphing or other operations where you must
have exact control over the number of vertices
created.
Creation Meth od rollout