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Offset Surfa ce 1187
Tension 2—
Controls tension at t he edge of the
second surface you clicked. This value has no
effectiftheedgeisacurve.
Flip End 1 and Flip End 2 —Flip one of the normals
used to construct the blend. A blend sur face is
created using the normals of the parent surfaces.
If the two parents have opposing normals, or
if a curve has the opposite direction, the blend
surface can be shaped like a bow tie. To correct
the situation, use Flip End 1 or Flip End 2 to
construct the blend using a normal opposite the
corresponding parent surface’s normal.
Flip Tangent 1 and Flip Tangent 2—Flip the t angent
attheedgeofthefirstorsecondcurveorsurface.
Flipping the tangent reverses the direction in
which the blend surface approaches the parent
sub-object at that edge.
Flipping the tangent has no effect if the edge is a
curve, unless the curve is a curve on surf ace.
When you blend to a CV or point curve on surface,
the new blend surface is tangent to the surface on
which the curve on surface lies. The Flip Tangent
controls are especially usef u l in this situation.
Start Point 1 and Star t Point 2—Adjust the position
of the start p oint at the two edges of the blend.
Adjusting the start points can help eliminate
unwanted twists or "buckles" in the surface.
These spi nners are unavailable if the edges or
cur ves are not closed.
While you’re adjusting start points, a dotted
blue line is displayed between them, to show the
alignment. The surface is not displayed, so it
doesn’t slow down adjustment. When you release
the mouse button, the su rface reappears.
Replace First Edge and R eplace Second Edge—Let
you replace the parent edges or curves. Click a
button, then click the edge to replace the orig i nal
first or second edge. The edge can be on the same
surface as the original edge, or on a different
surface.
Offset Surface
Select NURBS object. > Modify panel > Create Surfaces
rollout>DependentSurfacesgroupbox>Offset
Select N URBS obj ect. > Modify pane l > NURBS toolbox >
Create Offset Surface button
An Offset surface is offset a specified distance f rom
the original along the parent surface’ s normals.
Surface created as an offset
Procedure
To create an off set surf a ce:
1.
In a NURBS object that contains at least
one surface, turn on Offset.
2. Click the surface you want to offset, and drag to
set the initial distance of the offset surface.
Theoffsetsurfaceiscreated.
3. Adjust the Offset parameter.
Interf ace
While an offset surface sub-object is selected,
a rollout with the offset Distance parameter is
displayed at the bottom of the Modify panel.