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292 Chapter 5: Creating Geometry
R end er er—
Turn this on to specify Radial or
Rectangular parameters for the shape as it will
displaywhenrenderedorviewedintheviewport
when Enable in Viewport is turned on.
Radial—Displays the 3D mesh as a cylindrical
object.
Thick ness—Specifies the diameter of the viewp ort
or rendered spline mesh. Default=1.0. Range=0.0
to 100,000,000.0.
Splines rendered at thickness of 1.0 and 5.0, respectively
Sides—Sets the number of sides (or facets) for
thesplinemeshntheviewportorrenderer.For
example, a value of 4 results in a square cross
section.
Angle—Adjusts the rotational position of the
cross-section in the viewpor t or renderer. For
example, if the spline mesh has a square cross
section you can use Angle to position a "flat" side
down.
Rectangular—Displays the spline’s mesh shape as
rectangular.
Aspect—Sets the aspect ratio for rectangular
cross-sections. The Lo ck check box lets you lock
the aspect ratio. When Lock is tu rned on, Width
is locked to Depth that results in a constant ratio
of Width to Depth.
Lengt h—Specifies the size of the cross–section
along the local Y axis.
Width—Specifies the size of t he 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-sect ion you
can use Angle to position a "flat" side down.
Auto Smooth—If Auto Smooth is turned on, the
spline is auto-smoothed using the threshold
specified by the Threshold setting below it. Auto
Smooth sets the smoothing based on the angle
between spline segments. Any two adjacent
segmentsareputinthesamesmoothinggroupif
the angle between them is less t han the threshold
angle.
Threshold—Specifies the threshold angle in
degrees. Any two adjacent spline segments are put
inthesamesmoothinggroupiftheanglebetween
them is less than the threshold angle.
Interpolation rollout
The Interpolation controls set how the program
generates a spline. All spline curves are divided
into smal l st r aight lines that approximate the true
curve. The number of divisions between each
vertex on the spline is called steps.Themoresteps
used, the smoother the curve appears.
Splines used in above lathed objects contained two steps (left)
and 20 steps (right)
Steps—Use the Steps field to set the number of
divisions, or steps, the program uses between each
ver tex. Splines w ith tig ht curves require many
steps to look smooth while gentle curves require
fewer steps. Range=0 to 100.